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University of Maryland
1.
Chu, Edward.
Neural Modulation of Leg Stiffness in Response to Neuromuscular Fatigue.
Degree: Kinesiology, 2016, University of Maryland
URL: http://hdl.handle.net/1903/18667 
► The spring-mass model is able to accurately represent hopping spring-like behavior (leg and joint stiffness), and leg and joint stiffness changes can reveal overall motor…
(more)
▼ The spring-mass model is able to accurately represent hopping spring-like behavior (leg and joint
stiffness), and leg and joint
stiffness changes can reveal overall motor
control responses to neural and muscular contributors of neuromuscular fatigue. By understanding leg
stiffness modulation, we can determine which variables the nervous system targets to maintain motor performance and stability. The purpose of this study was to determine how neuromuscular fatigue affects hopping behavior by examining leg and joint
stiffness before and after a single-leg calf raise fatiguing protocol. Post-fatigue, leg
stiffness decreased for the exercised leg, but not for the non-exercised leg. Ankle and knee joint
stiffness did not significantly change for either leg. This indicates that leg
stiffness decreases primarily from muscular fatigue, but was not explained by ankle and knee joint
stiffness. The decrease in leg
stiffness may be an attempt to soften landing impact, while at the same time maintaining performance.
Advisors/Committee Members: Shim, Jae Kun (advisor), Miller, Ross H (advisor).
Subjects/Keywords: Biomechanics; Neurosciences; Fatigue; Joint Stiffness; Leg Stiffness; Locomotion; Motor Control; Neuromuscular
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APA (6th Edition):
Chu, E. (2016). Neural Modulation of Leg Stiffness in Response to Neuromuscular Fatigue. (Thesis). University of Maryland. Retrieved from http://hdl.handle.net/1903/18667
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Chu, Edward. “Neural Modulation of Leg Stiffness in Response to Neuromuscular Fatigue.” 2016. Thesis, University of Maryland. Accessed January 28, 2021.
http://hdl.handle.net/1903/18667.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Chu, Edward. “Neural Modulation of Leg Stiffness in Response to Neuromuscular Fatigue.” 2016. Web. 28 Jan 2021.
Vancouver:
Chu E. Neural Modulation of Leg Stiffness in Response to Neuromuscular Fatigue. [Internet] [Thesis]. University of Maryland; 2016. [cited 2021 Jan 28].
Available from: http://hdl.handle.net/1903/18667.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Chu E. Neural Modulation of Leg Stiffness in Response to Neuromuscular Fatigue. [Thesis]. University of Maryland; 2016. Available from: http://hdl.handle.net/1903/18667
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Alberta
2.
Azadi Sohi, Mojtaba.
Kinematically singular pre-stressed mechanisms as new
semi-active variable stiffness springs for vibration
isolation.
Degree: PhD, Department of Mechanical Engineering, 2010, University of Alberta
URL: https://era.library.ualberta.ca/files/g158bj19x
► Researchers have offered a variety of solutions for overcoming the old and challenging problem of undesired vibrations. The optimum vibration-control solution that can be a…
(more)
▼ Researchers have offered a variety of solutions for
overcoming the old and challenging problem of undesired vibrations.
The optimum vibration-control solution that can be a passive,
semi-active or active solution, is chosen based on the desired
level of vibration-control, the budget and the nature of the
vibration source. Mechanical vibration-control systems, which work
based on variable stiffness control, are categorized as semi-active
solutions. They are advantageous for applications with multiple
excitation frequencies, such as seismic applications. The available
mechanical variable stiffness systems that are used for
vibration-control, however, are slow and usually big, and their
slowness and size have limited their application. A new semi-active
variable stiffness solution is introduced and developed in this
thesis to address these challenges by providing a faster
vibration-control system with a feasible size. The new solution
proposed in this thesis is a semi-active variable stiffness
mount/isolator called the antagonistic Variable Stiffness Mount
(VSM), which uses a variable stiffness spring called the
Antagonistic Variable stiffness Spring (AVS). The AVS is a
kinematically singular prestressable mechanism. Its stiffness can
be changed by controlling the prestress of the mechanism’s links.
The AVS provides additional stiffness for a VSM when such stiffness
is needed and remains inactive when it is not needed. The damping
of the VSM is constant and an additional constant stiffness in the
VSM supports the deadweight. Two cable-mechanisms - kinematically
singular cable-driven mechanisms and Prism Tensegrities - are
developed as AVSs in this thesis. Their optimal configurations are
identified and a general formulation for their prestress stiffness
is provided by using the notion of infinitesimal mechanism. The
feasibility and practicality of the AVS and VSM are demonstrated
through a case study of a typical engine mount by simulation of the
mathematical models and by extensive experimental analysis. A VSM
with an adjustable design, a piezo-actuation mechanism and a simple
on-off controller is fabricated and tested for performance
evaluation. The performance is measured based on four criteria: (1)
how much the VSM controls the displacement near the resonance, (2)
how well the VSM isolates the vibration at high frequencies, (3)
how well the VSM controls the motion caused by shock, and (4) how
fast the VSM reacts to control the vibration. For this evaluation,
first the stiffness of the VSM was characterized through static and
dynamic tests. Then performance of the VSM was evaluated and
compared with an equivalent passive mount in two main areas of
transmissibility and shock absorption. The response time of the VSM
is also measured in a realistic scenario.
Subjects/Keywords: Stiffness control; Antagonistic Variable stiffness Spring; Variable stiffness engine mount; Cable driven parallel manipulator; Antagonistic stiffness; Compliance control; Prestressable mechanism; Vibration isolation; Semi active stiffness; Variable stiffness; Variable stiffness isolator; Variable stiffness spring; Vibration isolator; Prestress stiffness; Cable driven Mechanism; Antagonistic Variable Stiffness Mount; Singular Mechanism; Piezo-electric actuator; Tensegrity
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APA (6th Edition):
Azadi Sohi, M. (2010). Kinematically singular pre-stressed mechanisms as new
semi-active variable stiffness springs for vibration
isolation. (Doctoral Dissertation). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/g158bj19x
Chicago Manual of Style (16th Edition):
Azadi Sohi, Mojtaba. “Kinematically singular pre-stressed mechanisms as new
semi-active variable stiffness springs for vibration
isolation.” 2010. Doctoral Dissertation, University of Alberta. Accessed January 28, 2021.
https://era.library.ualberta.ca/files/g158bj19x.
MLA Handbook (7th Edition):
Azadi Sohi, Mojtaba. “Kinematically singular pre-stressed mechanisms as new
semi-active variable stiffness springs for vibration
isolation.” 2010. Web. 28 Jan 2021.
Vancouver:
Azadi Sohi M. Kinematically singular pre-stressed mechanisms as new
semi-active variable stiffness springs for vibration
isolation. [Internet] [Doctoral dissertation]. University of Alberta; 2010. [cited 2021 Jan 28].
Available from: https://era.library.ualberta.ca/files/g158bj19x.
Council of Science Editors:
Azadi Sohi M. Kinematically singular pre-stressed mechanisms as new
semi-active variable stiffness springs for vibration
isolation. [Doctoral Dissertation]. University of Alberta; 2010. Available from: https://era.library.ualberta.ca/files/g158bj19x
Temple University
3.
Russ, Anne C.
Sex, Hormones, and Use of Contraceptives on Muscle Strength and Activation.
Degree: PhD, 2012, Temple University
URL: http://digital.library.temple.edu/u?/p245801coll10,161946
► Kinesiology
Women are more likely to sustain knee injuries (e.g., ACL tears) than their male counterparts. The mechanisms responsible for this disparity are unclear. However…
(more)
▼ Kinesiology
Women are more likely to sustain knee injuries (e.g., ACL tears) than their male counterparts. The mechanisms responsible for this disparity are unclear. However fluctuating hormones during the menstrual cycle may be an influencing factor since more ACL injuries have been observed preceding ovulation when estrogen levels increase. Previous research shows females to have increased muscle strength and altered neuromuscular activation prior to ovulation. These findings have not been replicated in females using oral contraceptives (OC). To date, no study has examined all of these factors simultaneously. The purpose of this study was to determine the effect of sex, hormones, and contraceptive use on neuromuscular function at 3 points during a menstrual cycle. A prospective cohort design with independent variables of group [male (n=10), female no-OC (n=10), female OC (n=10)], and testing session (1,2,3) was used to assess knee function (i.e., tibial translation, isometric strength, vertical leg stiffness, and neuromuscular activation) on physically active college-aged participants. Three testing sessions were scheduled throughout a typical menstrual cycle. Tibial translation was measured at the start of each testing session to assess ACL laxity, for handgrip, knee extensors and knee flexors strength. Area EMG activity of the rectus femoris (representing quadriceps) and biceps femoris (representing hamstrings) was recorded over 3 46cm drop jumps, and vertical leg stiffness was calculated based on measurements obtained by a force plate. A 3 (group) x 3 (testing session) MANOVA (p ≤ 0.05) was used to assess knee function, as defined by tibial translation, strength, EMG activation and vertical leg stiffness. A significant difference was found with respect to strength, as males overall displayed greater strength than both female groups. No other significant differences were found. Although this study attempted to explain the effect of estrogen on strength and neuromuscular function with an improved design, no conclusive evidence was found to further explain this relationship. Future studies should use more sensitive and objective measures to explore this dynamic on a greater sample size over multiple menstrual cycle phases.
Temple University – Theses
Advisors/Committee Members: Yingling, Vanessa, Moffit, Dani M., Tierney, Ryan T., Stearne, David.
Subjects/Keywords: Kinesiology; Hormones; Knee; Laxity; Neuromuscular Control; Sex; Stiffness
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APA (6th Edition):
Russ, A. C. (2012). Sex, Hormones, and Use of Contraceptives on Muscle Strength and Activation. (Doctoral Dissertation). Temple University. Retrieved from http://digital.library.temple.edu/u?/p245801coll10,161946
Chicago Manual of Style (16th Edition):
Russ, Anne C. “Sex, Hormones, and Use of Contraceptives on Muscle Strength and Activation.” 2012. Doctoral Dissertation, Temple University. Accessed January 28, 2021.
http://digital.library.temple.edu/u?/p245801coll10,161946.
MLA Handbook (7th Edition):
Russ, Anne C. “Sex, Hormones, and Use of Contraceptives on Muscle Strength and Activation.” 2012. Web. 28 Jan 2021.
Vancouver:
Russ AC. Sex, Hormones, and Use of Contraceptives on Muscle Strength and Activation. [Internet] [Doctoral dissertation]. Temple University; 2012. [cited 2021 Jan 28].
Available from: http://digital.library.temple.edu/u?/p245801coll10,161946.
Council of Science Editors:
Russ AC. Sex, Hormones, and Use of Contraceptives on Muscle Strength and Activation. [Doctoral Dissertation]. Temple University; 2012. Available from: http://digital.library.temple.edu/u?/p245801coll10,161946
Brigham Young University
4.
Drake, Will Brandon.
Passive Stiffness of Coupled Wrist and Forearm Rotations.
Degree: MS, 2013, Brigham Young University
URL: https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=4445&context=etd
► The dynamics of wrist rotations are dominated by joint stiffness, which the neuromuscular system must account and compensate for when controlling wrist movements. Because wrist…
(more)
▼ The dynamics of wrist rotations are dominated by joint stiffness, which the neuromuscular system must account and compensate for when controlling wrist movements. Because wrist stiffness is anisotropic, movements in some directions require less torque than movements in others, creating opportunities to follow "paths of least resistance." Forearm pronation-supination (PS) can combine with wrist flexion-extension (FE) and radial-ulnar deviation (RUD) to allow the wrist to rotate in directions of least stiffness. Evaluating this hypothesis, and understanding the control of combined wrist and forearm rotations in general, requires a knowledge of the stiffness (the dominant mechanical impedance) encountered during combined wrist and forearm rotations. While wrist and forearm stiffness have been measured in isolation, there are no measurements of coupled wrist and the forearm stiffness. This study characterizes the passive stiffness of the wrist and forearm in combinations of FE, RUD, and PS. Using a wrist and forearm robot, we measured coupled wrist and forearm stiffness for 15° movements from neutral position in 10 young, healthy subjects. We found the stiffness in PS to be significantly smaller than the stiffness in RUD, but similar in magnitude to the stiffness in FE, indicating that the torque required to overcome stiffness in combinations of PS and FE is significantly smaller than the torque required to overcome stiffness in combinations of FE and RUD (assuming equal displacements). The coupled stiffness measured here will enable future studies to determine optimal paths and to compare these optimal paths to observed movements involving wrist and forearm rotations.
Subjects/Keywords: wrist; forearm; stiffness; passive; muscle tone; motor control; Mechanical Engineering
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APA (6th Edition):
Drake, W. B. (2013). Passive Stiffness of Coupled Wrist and Forearm Rotations. (Masters Thesis). Brigham Young University. Retrieved from https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=4445&context=etd
Chicago Manual of Style (16th Edition):
Drake, Will Brandon. “Passive Stiffness of Coupled Wrist and Forearm Rotations.” 2013. Masters Thesis, Brigham Young University. Accessed January 28, 2021.
https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=4445&context=etd.
MLA Handbook (7th Edition):
Drake, Will Brandon. “Passive Stiffness of Coupled Wrist and Forearm Rotations.” 2013. Web. 28 Jan 2021.
Vancouver:
Drake WB. Passive Stiffness of Coupled Wrist and Forearm Rotations. [Internet] [Masters thesis]. Brigham Young University; 2013. [cited 2021 Jan 28].
Available from: https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=4445&context=etd.
Council of Science Editors:
Drake WB. Passive Stiffness of Coupled Wrist and Forearm Rotations. [Masters Thesis]. Brigham Young University; 2013. Available from: https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=4445&context=etd
University of Colorado
5.
Yin, Hang.
Fabrication of Tissue-Mimetic Environments Using Projection Stereolithography.
Degree: MS, 2017, University of Colorado
URL: https://scholar.colorado.edu/mcen_gradetds/181
► The stiffness of an extracellular matrix (ECM) can exert great influence on cellular functions such as proliferation, migration and differentiation. Challenges still remain, however, in…
(more)
▼ The
stiffness of an extracellular matrix (ECM) can exert great influence on cellular functions such as proliferation, migration and differentiation. Challenges still remain, however, in the fabrication of artificial ECMs with well-controlled
stiffness profiles in three dimension (3D). In this thesis, we developed a projection micro-stereolithography system to fabricate 3D structures with quantitative
control over
stiffness using biocompatible materials. The technique is based on a grayscale printing method, which spatially controls the crosslinking density in the 3D hydrogel structures without influencing their appearance. Mimetic tissue environments in the form of 2D striped patterns and 3D tubes with
stiffness gradients were fabricated. Finally, we seeded bovine pulmonary arterial smooth muscle cells on these engineered environments, and during the culturing, cells migrated to stiffer regions. This work provides a method for fabricating tissue mimetic environments that can benefit the study of cellular behavior and other biomedical research.
Advisors/Committee Members: Xiaobo Yin, Wei Tan, Yifu Ding.
Subjects/Keywords: 3d printing; bio printing; pegdma; stereolithography; stiffness control; Biomedical; Mechanical Engineering
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APA (6th Edition):
Yin, H. (2017). Fabrication of Tissue-Mimetic Environments Using Projection Stereolithography. (Masters Thesis). University of Colorado. Retrieved from https://scholar.colorado.edu/mcen_gradetds/181
Chicago Manual of Style (16th Edition):
Yin, Hang. “Fabrication of Tissue-Mimetic Environments Using Projection Stereolithography.” 2017. Masters Thesis, University of Colorado. Accessed January 28, 2021.
https://scholar.colorado.edu/mcen_gradetds/181.
MLA Handbook (7th Edition):
Yin, Hang. “Fabrication of Tissue-Mimetic Environments Using Projection Stereolithography.” 2017. Web. 28 Jan 2021.
Vancouver:
Yin H. Fabrication of Tissue-Mimetic Environments Using Projection Stereolithography. [Internet] [Masters thesis]. University of Colorado; 2017. [cited 2021 Jan 28].
Available from: https://scholar.colorado.edu/mcen_gradetds/181.
Council of Science Editors:
Yin H. Fabrication of Tissue-Mimetic Environments Using Projection Stereolithography. [Masters Thesis]. University of Colorado; 2017. Available from: https://scholar.colorado.edu/mcen_gradetds/181
Delft University of Technology
6.
Doornebosch, Luuk (author).
The coupling effect in bilateral tele-impedance: Beneficial or detrimental for unstructured environment interaction?.
Degree: 2019, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:b485534c-88e8-44d8-84f4-7603afef2bf3
► Tele-impedance augments classical teleoperation by enabling the human operator to actively command remote robot stiffness. Hereby, an essential strategy used by humans to successfully interact…
(more)
▼ Tele-impedance augments classical teleoperation by enabling the human operator to actively command remote robot stiffness. Hereby, an essential strategy used by humans to successfully interact with the unstructured environment complements remote robot-environment interaction. However, literature lacks awareness of benefits and disbenefits of currently used stiffness command interfaces (SCIs) in bilateral tele-impedance. In this paper, we introduce a term called the coupling effect. The coupling effect pertains to the coupling between human initiated commanded stiffness and force-feedback from the master robot. It is hypothesized that, whenever the operator’s commanded stiffness and the master device are coupled, like in muscle activity based SCIs, force-feedback can invoke changes in the commanded stiffness due to human reflexes. Although the coupling effect takes away some degree of the operator’s control over the commanded stiffness, these involuntary changes can be either beneficial (e.g. during position tracking) or detrimental (e.g. during force tracking) to the task performance on the remote robot side. In an experimental study 16 participants perform position and force tracking tasks by using both an EMG based coupled type and an external device based decoupled type of SCI. Our results demonstrate a benefit of the coupling effect by showing lower absolute position error during the unexpected force perturbation when a coupled SCI was is in the position task. The coupling effect does not affect reference stiffness tracking in the force task during the process of establishing contact compared to maintaining reference force when a coupled SCI is used. The decoupled SCI is beneficial for tracking reference force in the force task and tracking reference stiffness for both tasks. We conclude that—when using bilateral tele-impedance—one should be aware of the coupling effect, which is beneficial for rejecting a disturbance in a position tracking task but detrimental for establishing contact in a force tracking task.
Mechanical Engineering | BioMechanical Design
Advisors/Committee Members: Peternel, Luka (mentor), Abbink, David (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Tele-impedance; Force-feedback; Coupling effect; Impedance control; Stiffness Command Interface
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APA (6th Edition):
Doornebosch, L. (. (2019). The coupling effect in bilateral tele-impedance: Beneficial or detrimental for unstructured environment interaction?. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:b485534c-88e8-44d8-84f4-7603afef2bf3
Chicago Manual of Style (16th Edition):
Doornebosch, Luuk (author). “The coupling effect in bilateral tele-impedance: Beneficial or detrimental for unstructured environment interaction?.” 2019. Masters Thesis, Delft University of Technology. Accessed January 28, 2021.
http://resolver.tudelft.nl/uuid:b485534c-88e8-44d8-84f4-7603afef2bf3.
MLA Handbook (7th Edition):
Doornebosch, Luuk (author). “The coupling effect in bilateral tele-impedance: Beneficial or detrimental for unstructured environment interaction?.” 2019. Web. 28 Jan 2021.
Vancouver:
Doornebosch L(. The coupling effect in bilateral tele-impedance: Beneficial or detrimental for unstructured environment interaction?. [Internet] [Masters thesis]. Delft University of Technology; 2019. [cited 2021 Jan 28].
Available from: http://resolver.tudelft.nl/uuid:b485534c-88e8-44d8-84f4-7603afef2bf3.
Council of Science Editors:
Doornebosch L(. The coupling effect in bilateral tele-impedance: Beneficial or detrimental for unstructured environment interaction?. [Masters Thesis]. Delft University of Technology; 2019. Available from: http://resolver.tudelft.nl/uuid:b485534c-88e8-44d8-84f4-7603afef2bf3
McMaster University
7.
Holmes, WR Michael.
A BIOMECHANICAL EVALUATION OF LIGAMENT AND MUSCULAR STIFFNESS IN THE DISTAL UPPER EXTREMITY.
Degree: PhD, 2011, McMaster University
URL: http://hdl.handle.net/11375/9933
► The purpose of this thesis was to evaluate musculoskeletal contributions to joint stiffness in the distal upper extremity. An in-vitro and in-vivo approach was…
(more)
▼ The purpose of this thesis was to evaluate musculoskeletal contributions to joint stiffness in the distal upper extremity. An in-vitro and in-vivo approach was used to examine muscle and ligament contributions to mechanical joint stiffness at the elbow and wrist. In Chapters 2 and 3 an in-vitro approach was used to evaluate ligament contributions to carpal tunnel mechanics. Chapter 2 documented transverse carpal ligament (TCL) mechanical properties and provided a calculation of TCL length when stretched, which confirmed the ligaments importance in carpal tunnel mechanics and carpal bone stability. Chapter 3 quantified mechanical properties of the TCL at six different locations using a biaxial tensile testing method. It was found that the complex TCL fibre arrangement makes the tissue properties location dependent. The TCL contributes to carpal tunnel mechanics and carpal stability and the ligament contributions are different depending on the tissue location tested. Chapters 4 and 5 focused on the effects of hand loads and arm postures on the muscular response to sudden arm perturbations. The elbow flexors demonstrated stiffness contributions immediately prior to a perturbation and were influenced by posture and hand loading. The forearm muscles provided a small contribution to elbow joint stiffness. Chapter 6 also found muscular contributions that increased wrist joint stiffness immediately prior to a sudden perturbation. Additionally, for a small grip-demanding task, forearm muscle co-contraction resulted in large increases in wrist joint stiffness. This thesis has provided a detailed analysis of the TCL which improves our understanding of the carpal tunnel and specific mechanisms of injury. It is the first to document individual muscle contributions to elbow and wrist joint stiffness. The comprehensive analysis of ligament and muscular contributions to joint stiffness has provided insight into joint stability in the distal upper extremity. This can improve our understanding of injury caused by sudden joint loading.
Doctor of Philosophy (PhD)
Advisors/Committee Members: Keir, Peter, Jim Potvin, Michael Pierrynowski, Jim Potvin, Michael Pierrynowski, Kinesiology.
Subjects/Keywords: Distal Upper Extremity; Stability; Muscle Stiffness; Ligament Stiffness; Cadaver; Occupational Biomechanics; Biomechanical Engineering; Biomechanics; Motor Control; Biomechanical Engineering
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APA (6th Edition):
Holmes, W. M. (2011). A BIOMECHANICAL EVALUATION OF LIGAMENT AND MUSCULAR STIFFNESS IN THE DISTAL UPPER EXTREMITY. (Doctoral Dissertation). McMaster University. Retrieved from http://hdl.handle.net/11375/9933
Chicago Manual of Style (16th Edition):
Holmes, WR Michael. “A BIOMECHANICAL EVALUATION OF LIGAMENT AND MUSCULAR STIFFNESS IN THE DISTAL UPPER EXTREMITY.” 2011. Doctoral Dissertation, McMaster University. Accessed January 28, 2021.
http://hdl.handle.net/11375/9933.
MLA Handbook (7th Edition):
Holmes, WR Michael. “A BIOMECHANICAL EVALUATION OF LIGAMENT AND MUSCULAR STIFFNESS IN THE DISTAL UPPER EXTREMITY.” 2011. Web. 28 Jan 2021.
Vancouver:
Holmes WM. A BIOMECHANICAL EVALUATION OF LIGAMENT AND MUSCULAR STIFFNESS IN THE DISTAL UPPER EXTREMITY. [Internet] [Doctoral dissertation]. McMaster University; 2011. [cited 2021 Jan 28].
Available from: http://hdl.handle.net/11375/9933.
Council of Science Editors:
Holmes WM. A BIOMECHANICAL EVALUATION OF LIGAMENT AND MUSCULAR STIFFNESS IN THE DISTAL UPPER EXTREMITY. [Doctoral Dissertation]. McMaster University; 2011. Available from: http://hdl.handle.net/11375/9933
8.
SALEM, MOHAMED M. A.
Seismic Response Control Of Structures Using Semi-Active and Passive Variable Stiffness Devices.
Degree: 2014, University of Nevada – Reno
URL: http://hdl.handle.net/11714/2876
► Controllable devices such as Magneto-Rheological Fluid Dampers, Electro-Rheological Dampers, and controllable friction devices have been studied extensively with limited implementation in real structures. Such devices…
(more)
▼ Controllable devices such as Magneto-Rheological Fluid Dampers, Electro-Rheological Dampers, and controllable friction devices have been studied extensively with limited implementation in real structures. Such devices have shown great potential in reducing seismic demands, either as smart base isolation systems, or as smart devices for multistory structures. Although variable
stiffness devices can be used for seismic
control of structures, the vast majority of research effort has been given to the
control of damping.The primary focus of this dissertation is to evaluate the seismic
control of structures using semi-active and passive variable
stiffness characteristics. Smart base isolation systems employing variable
stiffness devices have been studied, and two semi-active
control strategies are proposed. The
control algorithms were designed to reduce the superstructure and base accelerations of seismically isolated structures
subject to near-fault and far-field ground motions. Computational simulations of the proposed
control algorithms on the benchmark structure have shown that excessive base displacements associated with the near-fault ground motions may be better mitigated with the use of variable
stiffness devices. However, the device properties must be controllable to produce a wide range of
stiffness changes for an effective
control of the base displacements. The potential of controllable
stiffness devices in limiting the base displacement due to near-fault excitation without compromising the performance of conventionally isolated structures, is illustrated.The application of passive variable
stiffness devices for seismic response mitigation of multistory structures is also investigated. A stiffening bracing system (SBS) is proposed to replace the conventional bracing systems of braced frames. An optimization process for the SBS parameters has been developed. The main objective of the design process is to maintain a uniform inter-story drift angle over the building's height, which in turn would evenly distribute the seismic demand over the building. This behavior is particularly essential so that any possible damage is not concentrated in a single story. Furthermore, the proposed design ensures that additional damping devices distributed over the building's height work efficiently with their maximum design capacity, leading to a cost efficient design. An integrated and comprehensive design procedure that can be readily adopted by the current seismic design codes is proposed. An equivalent lateral force distribution is developed that shows a good agreement with the response history analyses in terms of seismic performance and demand prediction. This lateral force pattern explicitly accounts for the higher mode effect, the dynamic characteristics of the structure, the supplemental damping, and the site specific seismic hazard. Therefore, the proposed design procedure is considered as a standalone method for the design of SBS equipped buildings.
Advisors/Committee Members: Pekcan, Gokhan (advisor), Itani, Ahmad M. (advisor), Buckle, Ian G. (committee member), Fadali, M. Sami (committee member), Anderson, John (committee member).
Subjects/Keywords: Seismic response control; semi-active; smart base isolation; stiffening brace; stiffness optimization; uniform drift; variable stiffness
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APA (6th Edition):
SALEM, M. M. A. (2014). Seismic Response Control Of Structures Using Semi-Active and Passive Variable Stiffness Devices. (Thesis). University of Nevada – Reno. Retrieved from http://hdl.handle.net/11714/2876
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
SALEM, MOHAMED M A. “Seismic Response Control Of Structures Using Semi-Active and Passive Variable Stiffness Devices.” 2014. Thesis, University of Nevada – Reno. Accessed January 28, 2021.
http://hdl.handle.net/11714/2876.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
SALEM, MOHAMED M A. “Seismic Response Control Of Structures Using Semi-Active and Passive Variable Stiffness Devices.” 2014. Web. 28 Jan 2021.
Vancouver:
SALEM MMA. Seismic Response Control Of Structures Using Semi-Active and Passive Variable Stiffness Devices. [Internet] [Thesis]. University of Nevada – Reno; 2014. [cited 2021 Jan 28].
Available from: http://hdl.handle.net/11714/2876.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
SALEM MMA. Seismic Response Control Of Structures Using Semi-Active and Passive Variable Stiffness Devices. [Thesis]. University of Nevada – Reno; 2014. Available from: http://hdl.handle.net/11714/2876
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Wollongong
9.
Sun, Shuaishuai.
Semi-active MR technology for enhancing vehicle stability and ride comfort.
Degree: PhD, 2016, University of Wollongong
URL: 0902
AUTOMOTIVE
ENGINEERING,
0910
MANUFACTURING
ENGINEERING,
0912
MATERIALS
ENGINEERING,
0913
MECHANICAL
ENGINEERING
;
https://ro.uow.edu.au/theses/4805
► With the popularisation and rapid development of railway transportation, how to maintain train stability and reduce unwanted vibration to make the ride more comfortable…
(more)
▼ With the popularisation and rapid development of railway transportation, how to maintain train stability and reduce unwanted vibration to make the ride more comfortable has become an emerging research topic. This is why this project has included magnetorheological (MR) technology into railway vehicles to improve their performance.
Critical speed is an index and a key technology that directly indicates train stability, which is why the critical speeds of trains are calculated and analysed based on the dynamic equations of railway vehicles. These analyses revealed that secondary lateral damping and primary longitudinal stiffness are the most sensitive suspension parameters influencing critical speeds. In an attempt to improve dynamic performance, the secondary lateral dampers were replaced with conventional magnetorheological fluid (MRF) dampers; with the simulation and experimental results indicating that the semi-active suspension installed with MR dampers raised the critical speed and achieved a higher level of stability. The primary longitudinal stiffness is meant to be stiff when a train is running straight to maintain the stability and then soft when the train is turning, for better trafficability. To solve this dilemma, an innovative magnetorheological elastomer (MRE) based primary longitudinal rubber joint with variable stiffness characteristics has been developed. The simulation shows that controlling the MRE joint when a train runs on straight and curved track can satisfy these apparently conflicting requirements and realise good trafficability on curved track and high stability on straight track.
Subjects/Keywords: railway vehicle; MR technology; vibration control; train stability; seat suspension; variable stiffness and damping
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APA (6th Edition):
Sun, S. (2016). Semi-active MR technology for enhancing vehicle stability and ride comfort. (Doctoral Dissertation). University of Wollongong. Retrieved from 0902 AUTOMOTIVE ENGINEERING, 0910 MANUFACTURING ENGINEERING, 0912 MATERIALS ENGINEERING, 0913 MECHANICAL ENGINEERING ; https://ro.uow.edu.au/theses/4805
Chicago Manual of Style (16th Edition):
Sun, Shuaishuai. “Semi-active MR technology for enhancing vehicle stability and ride comfort.” 2016. Doctoral Dissertation, University of Wollongong. Accessed January 28, 2021.
0902 AUTOMOTIVE ENGINEERING, 0910 MANUFACTURING ENGINEERING, 0912 MATERIALS ENGINEERING, 0913 MECHANICAL ENGINEERING ; https://ro.uow.edu.au/theses/4805.
MLA Handbook (7th Edition):
Sun, Shuaishuai. “Semi-active MR technology for enhancing vehicle stability and ride comfort.” 2016. Web. 28 Jan 2021.
Vancouver:
Sun S. Semi-active MR technology for enhancing vehicle stability and ride comfort. [Internet] [Doctoral dissertation]. University of Wollongong; 2016. [cited 2021 Jan 28].
Available from: 0902 AUTOMOTIVE ENGINEERING, 0910 MANUFACTURING ENGINEERING, 0912 MATERIALS ENGINEERING, 0913 MECHANICAL ENGINEERING ; https://ro.uow.edu.au/theses/4805.
Council of Science Editors:
Sun S. Semi-active MR technology for enhancing vehicle stability and ride comfort. [Doctoral Dissertation]. University of Wollongong; 2016. Available from: 0902 AUTOMOTIVE ENGINEERING, 0910 MANUFACTURING ENGINEERING, 0912 MATERIALS ENGINEERING, 0913 MECHANICAL ENGINEERING ; https://ro.uow.edu.au/theses/4805
University of Colorado
10.
Yin, Hang.
Fabrication of Tissue-Mimetic Environments Using Projection Stereolithography.
Degree: MS, Mechanical Engineering, 2017, University of Colorado
URL: https://scholar.colorado.edu/mcen_gradetds/139
► The stiffness of an extracellular matrix (ECM) can exert great influence on cellular functions such as proliferation, migration and differentiation. Challenges still remain, however, in…
(more)
▼ The
stiffness of an extracellular matrix (ECM) can exert great influence on cellular functions such as proliferation, migration and differentiation. Challenges still remain, however, in the fabrication of artificial ECMs with well-controlled
stiffness profiles in three dimension (3D). In this thesis, we developed a projection micro-stereolithography system to fabricate 3D structures with quantitative
control over
stiffness using biocompatible materials. The technique is based on a grayscale printing method, which spatially controls the crosslinking density in the 3D hydrogel structures without influencing their appearance. Mimetic tissue environments in the form of 2D striped patterns and 3D tubes with
stiffness gradients were fabricated. Finally, we seeded bovine pulmonary arterial smooth muscle cells on these engineered environments, and during the culturing, cells migrated to stiffer regions. This work provides a method for fabricating tissue mimetic environments that can benefit the study of cellular behavior and other biomedical research.
Advisors/Committee Members: Xiaobo Yin, Wei Tan, Yifu Ding.
Subjects/Keywords: 3D printing; Bio printing; PEGDMA; Stereolithography; Stiffness control; Biomechanical Engineering; Mechanical Engineering
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Chicago ·
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CSE |
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Manager
APA (6th Edition):
Yin, H. (2017). Fabrication of Tissue-Mimetic Environments Using Projection Stereolithography. (Masters Thesis). University of Colorado. Retrieved from https://scholar.colorado.edu/mcen_gradetds/139
Chicago Manual of Style (16th Edition):
Yin, Hang. “Fabrication of Tissue-Mimetic Environments Using Projection Stereolithography.” 2017. Masters Thesis, University of Colorado. Accessed January 28, 2021.
https://scholar.colorado.edu/mcen_gradetds/139.
MLA Handbook (7th Edition):
Yin, Hang. “Fabrication of Tissue-Mimetic Environments Using Projection Stereolithography.” 2017. Web. 28 Jan 2021.
Vancouver:
Yin H. Fabrication of Tissue-Mimetic Environments Using Projection Stereolithography. [Internet] [Masters thesis]. University of Colorado; 2017. [cited 2021 Jan 28].
Available from: https://scholar.colorado.edu/mcen_gradetds/139.
Council of Science Editors:
Yin H. Fabrication of Tissue-Mimetic Environments Using Projection Stereolithography. [Masters Thesis]. University of Colorado; 2017. Available from: https://scholar.colorado.edu/mcen_gradetds/139
University of Manitoba
11.
Ghorbani, Reza.
On controllable stiffness bipedal walking.
Degree: Mechanical and Manufacturing Engineering, 2008, University of Manitoba
URL: http://hdl.handle.net/1993/3040
► Impact at each leg transition is one of the main causes of energy dissipation in most of the current bipedal walking robots. Minimizing impact can…
(more)
▼ Impact at each leg transition is one of the main causes of energy dissipation in most
of the current bipedal walking robots. Minimizing impact can reduce the energy loss.
Instead of controlling the joint angle profiles to reduce the impact which requires significant
amount of energy, installing elastic mechanisms on the robots structure is
proposed in this research, enabling the robot to reduce the impact, and to store part
of the energy in the elastic form which returns the energy to the robot. Practically,
this motivates the development of the bipedal walking robots with adjustable
stiffness
elasticity which itself creates new challenging problems. This thesis addresses some of
the challenges through five consecutive stages. Firstly, an adjustable compliant series
elastic actuator (named ACSEA in this thesis) is developed. The velocity
control mode
of the electric motor is used to accurately
control the output force of the ACSEA. Secondly,
three different conceptual designs of the adjustable
stiffness artificial tendons
(ASAT) are proposed each of which is added at the ankle joint of a bipedal walking
robot model. Simulation results of the collision phase (part of the gait between
the heel-strike and the foot-touch-down in bipedal walking) demonstrate significant
improvements in the energetics of the bipedal walking robot by proper
stiffness adjustment
of ASAT. In the third stage, in order to study the effects of ASATs on reducing
the energy loss during the stance phase, a simplified model of bipedal walking is introduced
consisting of a foot, a leg and an ASAT which is installed parallel to the ankle
joint. A linear spring, with adjustable
stiffness, is included in the model to simulate the generated force by the trailing leg during the double support phase. The concept
of impulsive constraints is used to establish the mathematical model of impacts in
the collision phase which includes the heel-strike and the foot-touch-down. For the
fourth stage, an energy-feedback-based controller is designed to automatically adjust
the
stiffness of the ASAT which reduces the energy loss during the foot-touch-down.
In the final stage, a speed tracking (ST) controller is developed to regulate the velocity
of the biped at the midstance. The ST controller is an event-based time-independent
controller, based on geometric progression with exponential decay in the kinetic energy
error, which adjusts the
stiffness of the trailing-leg spring to
control the injected energy
to the biped in tracking a desired speed at the midstance. Another controller is also
integrated with the ST controller to tune the
stiffness of the ASAT when reduction in
the speed is desired. Then, the local stability of the system (biped and the combination
of the above three controllers) is analyzed by calculating the eigenvalues of the linear
approximation of the return map. Simulation results show that the combination of the
three controllers is successful in tracking a desired speed of the bipedal walking even
in the presence of…
Advisors/Committee Members: (Mechanical and Manufacturing Engineering) (supervisor), Spong, Mark (Department of Electrical and Computer Engineering University of Illinois at Urbana-Champaign).
Subjects/Keywords: Bipedal walking; Adjustable Stiffness; Control; Robot
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APA ·
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MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ghorbani, R. (2008). On controllable stiffness bipedal walking. (Thesis). University of Manitoba. Retrieved from http://hdl.handle.net/1993/3040
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Ghorbani, Reza. “On controllable stiffness bipedal walking.” 2008. Thesis, University of Manitoba. Accessed January 28, 2021.
http://hdl.handle.net/1993/3040.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ghorbani, Reza. “On controllable stiffness bipedal walking.” 2008. Web. 28 Jan 2021.
Vancouver:
Ghorbani R. On controllable stiffness bipedal walking. [Internet] [Thesis]. University of Manitoba; 2008. [cited 2021 Jan 28].
Available from: http://hdl.handle.net/1993/3040.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ghorbani R. On controllable stiffness bipedal walking. [Thesis]. University of Manitoba; 2008. Available from: http://hdl.handle.net/1993/3040
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Manchester
12.
Rafique, Sajid.
Piezoelectric vibration energy harvesting and its application to vibration control.
Degree: PhD, 2012, University of Manchester
URL: https://www.research.manchester.ac.uk/portal/en/theses/piezoelectric-vibration-energy-harvesting-and-its-application-to-vibration-control(d9edcedf-054e-4921-9ba3-5e015b9bbd8f).html
;
http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553389
► Vibration-based energy harvesting using piezoelectric materials have been investigated by several research groups with the aim of harvesting maximum energy and providing power to low-powered…
(more)
▼ Vibration-based energy harvesting using piezoelectric materials have been investigated by several research groups with the aim of harvesting maximum energy and providing power to low-powered wireless electronic systems for their entire operational life. The electromechanical coupling effect introduced by the piezoelectric vibration energy harvesting (PVEH) mechanism presents modelling challenges. For this reason, there has been a continuous effort to develop different modelling techniques to describe the PVEH mechanism and its effects on the dynamics of the system. The overall aims of this thesis are twofold: (1) a thorough theoretical and experimental analysis of a PVEH beam or assembly of beams; (2) an in-depth analytical and experimental investigation of the novel concept of a dual function piezoelectric vibration energy harvester beam/tuned vibration absorber (PVEH/TVA) or 'electromechanical TVA' and its potential application to vibration control. The salient novel contributions of this thesis can be summarised as follows: (i) An in-depth experimental validation of a PVEH beam model based on the analytical modal analysis method (AMAM), with the investigations conducted over a wider frequency range than previously tested. (ii) The precise identification of the electrical loads that harvest maximum power and that induce maximum electrical damping. (iii) A thorough investigation of the influence of mechanical damping on PVEH beams. (iv) A procedure for the exact modelling of PVEH beams, and assemblies of such beams, using the dynamic stiffness matrix (DSM) method. (v) A procedure to enhance the power output from a PVEH beam through the application of a tip rotational restraint and the use of segmented electrodes. (vi) The theoretical basis for the novel concept of a dual function PVEH beam/TVA, and its realisation and experimental validation for a prototype device. A thorough experimental validation of a cantilever piezoelectric bimorph energy harvester without a tip mass is presented under random excitation. The study provided a deep insight into the effect of PVEH on the dynamics of the system for variations in electrical load. An alternative modelling technique to AMAM, based on the DSM, is introduced for PVEH beams. Unlike AMAM, the DSM is exact, since it is based on the exact solution to the bending wave equation. It also readily lends itself to the modelling of beams with different boundary conditions or assemblies of beams of different crosssections. AMAM is shown to converge to DSM if a sufficiency of modes is used. Finally, an in-depth theoretical and experimental investigation of a prototype PVEHbeam/TVA device is presented. This device comprises a pair of bimorphs shunted by R-L-C circuitry and can be used as a tuned mass damper (TMD) to attenuate a vibration mode of a generic structure. The optimal damping required by this TMD is generated by the PVEH effect of the bimorphs. Such a device combines the advantages of conventional mechanical and electrical TVAs, overcoming their relative disadvantages. The…
Subjects/Keywords: 620.37; Energy Harvesting; Vibration Control; Energy harvesting TVA; Damping; Piezoelectric; Dynamic Stiffness Method; AMAM
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Manager
APA (6th Edition):
Rafique, S. (2012). Piezoelectric vibration energy harvesting and its application to vibration control. (Doctoral Dissertation). University of Manchester. Retrieved from https://www.research.manchester.ac.uk/portal/en/theses/piezoelectric-vibration-energy-harvesting-and-its-application-to-vibration-control(d9edcedf-054e-4921-9ba3-5e015b9bbd8f).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553389
Chicago Manual of Style (16th Edition):
Rafique, Sajid. “Piezoelectric vibration energy harvesting and its application to vibration control.” 2012. Doctoral Dissertation, University of Manchester. Accessed January 28, 2021.
https://www.research.manchester.ac.uk/portal/en/theses/piezoelectric-vibration-energy-harvesting-and-its-application-to-vibration-control(d9edcedf-054e-4921-9ba3-5e015b9bbd8f).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553389.
MLA Handbook (7th Edition):
Rafique, Sajid. “Piezoelectric vibration energy harvesting and its application to vibration control.” 2012. Web. 28 Jan 2021.
Vancouver:
Rafique S. Piezoelectric vibration energy harvesting and its application to vibration control. [Internet] [Doctoral dissertation]. University of Manchester; 2012. [cited 2021 Jan 28].
Available from: https://www.research.manchester.ac.uk/portal/en/theses/piezoelectric-vibration-energy-harvesting-and-its-application-to-vibration-control(d9edcedf-054e-4921-9ba3-5e015b9bbd8f).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553389.
Council of Science Editors:
Rafique S. Piezoelectric vibration energy harvesting and its application to vibration control. [Doctoral Dissertation]. University of Manchester; 2012. Available from: https://www.research.manchester.ac.uk/portal/en/theses/piezoelectric-vibration-energy-harvesting-and-its-application-to-vibration-control(d9edcedf-054e-4921-9ba3-5e015b9bbd8f).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553389
University of Florida
13.
Laplassotte, Celine.
Needle Insertion for Robotic Surgery.
Degree: MS, Mechanical Engineering - Mechanical and Aerospace Engineering, 2012, University of Florida
URL: https://ufdc.ufl.edu/UFE0044791
► Many modern clinical practices involve percutaneous needle insertion. This thesis focuses on modeling and automation aspects related to robotic needle insertion. Medical robotics may offer…
(more)
▼ Many modern clinical practices involve percutaneous needle insertion. This thesis focuses on modeling and automation aspects related to robotic needle insertion. Medical robotics may offer methods for improving such practices. The first contribution is the development of a controller to ensure that a needle tip tracks a trajectory beginning in a non-contact position and ending within viscoelastic tissue. Through employment of a sliding mode controller and a neural network (NN), the controller guarantees semi-global asymptotic tracking of the desired trajectory. The second contribution is the development of a controller to ensure that a needle tip mounted on a slave robot tracks the trajectory given by the surgeon manipulating the master robot, in the presence of uncertainties in the user and environment forces. The
control development leads to semi-global asymptotic tracking of the desired trajectory using a sliding mode controller and a NN. Lyapunov-based stability analysis and simulations are provided to demonstrate the performance of the
control designs throughout the thesis. ( en )
Advisors/Committee Members: Dixon, Warren E (committee chair), Crane, Carl D (committee member).
Subjects/Keywords: Body tissues; International conferences; Modeling; Needles; Robotics; Robots; Simulations; Slavery; Stiffness; Trajectories; control – needle – robotics
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APA (6th Edition):
Laplassotte, C. (2012). Needle Insertion for Robotic Surgery. (Masters Thesis). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0044791
Chicago Manual of Style (16th Edition):
Laplassotte, Celine. “Needle Insertion for Robotic Surgery.” 2012. Masters Thesis, University of Florida. Accessed January 28, 2021.
https://ufdc.ufl.edu/UFE0044791.
MLA Handbook (7th Edition):
Laplassotte, Celine. “Needle Insertion for Robotic Surgery.” 2012. Web. 28 Jan 2021.
Vancouver:
Laplassotte C. Needle Insertion for Robotic Surgery. [Internet] [Masters thesis]. University of Florida; 2012. [cited 2021 Jan 28].
Available from: https://ufdc.ufl.edu/UFE0044791.
Council of Science Editors:
Laplassotte C. Needle Insertion for Robotic Surgery. [Masters Thesis]. University of Florida; 2012. Available from: https://ufdc.ufl.edu/UFE0044791
University of Southern California
14.
Lyle, Mark A.
Quantification of lower extremity dynamic capability:
implications for anterior cruciate ligament injury and change of
direction ability.
Degree: PhD, Biokinesiology, 2012, University of Southern California
URL: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/16892/rec/5348
► Anterior cruciate ligament (ACL) tears are serious injuries that occur at a higher rate in female athletes when compared to male athletes. Despite considerable research…
(more)
▼ Anterior cruciate ligament (ACL) tears are serious
injuries that occur at a higher rate in female athletes when
compared to male athletes. Despite considerable research
investigating this complex sports medicine problem, the primary
factor(s) that underlie the sex disparity in ACL injury remains
unknown. Recent literature suggests that diminished lower extremity
control may increase the risk of ACL injury in females. The primary
objective of this dissertation was to develop a method designed to
quantify the capability of the lower limb to dynamically interact
with the ground (i.e., the lower extremity dexterity test, or
LED-test), and to evaluate whether this method is reliable and
informative of lower extremity function in the context of ACL
injury risk and change of direction ability. In Chapter III, the
LED-test is described, test-retest reliability was assessed, and
the extent to which performance was associated with lower limb
strength and anthropometry was examined. Test-retest reliability
was excellent (ICC = 0.94) and LED-test performance was found to be
independent of strength and anthropometry suggesting that the test
was capable of quantifying a unique construct. The purpose of
Chapter IV was to compare LED-test performance between female and
male soccer athletes. Lower extremity biomechanics during a single
limb drop jump also were examined. Results revealed that the female
athletes exhibited reduced lower extremity dexterity as assessed by
the LED-test when compared to the male athletes. Females also were
found to land using a movement strategy that has been implicated as
increasing the risk of ACL injury (i.e. increased limb
stiffness).
Our findings suggest that the movement behavior exhibited by the
female athletes may represent a heightened feedforward
control
strategy to compensate for reduced lower extremity dexterity. The
purpose of Chapter V was to determine the extent to which LED-test
performance (as opposed to lower limb strength and power) was
associated with change of direction ability (i.e. agility) in high
school soccer athletes. Results revealed that lower extremity
dexterity was highly correlated with agility in both males and
females, whereas lower limb strength and power were not correlated
with agility. Dexterity was the primary predictor of agility
performance, explaining almost 50% of the variance in agility after
controlling for sex. Overall, the findings of this dissertation
indicate that the LED-test measures a unique construct reflective
of dynamic lower extremity
control. In addition, data from this
dissertation suggest that diminished lower extremity dexterity as
quantified by the LED-test may influence lower extremity movement
patterns considered to place female athletes at risk for ACL
injury. Moreover, the results provide evidence that the LED-test
quantifies an experimental construct that reveals a dimension of
dynamic function that is informative of change of direction
ability. As such, impaired lower extremity dexterity may not only
contribute to limb mechanics that…
Advisors/Committee Members: Powers, Christopher M. (Committee Chair), Gregor, Robert J. (Committee Member), Valero-Cuevas, Francisco J. (Committee Member), Gordon, James G. (Committee Member), Keim, Robert G. (Committee Member).
Subjects/Keywords: ACL injury; sex differences; dexterity; lower extremity; landing; leg stiffness; sensorimotor control; agility
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lyle, M. A. (2012). Quantification of lower extremity dynamic capability:
implications for anterior cruciate ligament injury and change of
direction ability. (Doctoral Dissertation). University of Southern California. Retrieved from http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/16892/rec/5348
Chicago Manual of Style (16th Edition):
Lyle, Mark A. “Quantification of lower extremity dynamic capability:
implications for anterior cruciate ligament injury and change of
direction ability.” 2012. Doctoral Dissertation, University of Southern California. Accessed January 28, 2021.
http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/16892/rec/5348.
MLA Handbook (7th Edition):
Lyle, Mark A. “Quantification of lower extremity dynamic capability:
implications for anterior cruciate ligament injury and change of
direction ability.” 2012. Web. 28 Jan 2021.
Vancouver:
Lyle MA. Quantification of lower extremity dynamic capability:
implications for anterior cruciate ligament injury and change of
direction ability. [Internet] [Doctoral dissertation]. University of Southern California; 2012. [cited 2021 Jan 28].
Available from: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/16892/rec/5348.
Council of Science Editors:
Lyle MA. Quantification of lower extremity dynamic capability:
implications for anterior cruciate ligament injury and change of
direction ability. [Doctoral Dissertation]. University of Southern California; 2012. Available from: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/16892/rec/5348
Virginia Tech
15.
Zhang, Hong Bo.
Developing and Evaluating New Methods for Assessing Postural Control and Dynamics.
Degree: PhD, Industrial and Systems Engineering, 2013, Virginia Tech
URL: http://hdl.handle.net/10919/19289
► Falls are the leading cause of injuries among older adults (>65) and frequently result in reduced mobility, loss of independence, decreased quality of life, injury,…
(more)
▼ Falls are the leading cause of injuries among older adults (>65) and frequently result in reduced mobility, loss of independence, decreased quality of life, injury, and death. Extensive research has been conducted regarding postural coordination and
control, and other mechanisms/processes involved in maintaining postural stability. However, there is relatively limited knowledge regarding the patterns of joint coordination, the underlying postural controller, and efficient methods to assess passive and active musculoskeletal properties relevant to balance. In the current work, three new methods were developed to address these limitations and also to better understand the effects of localized ankle muscle fatigue, gender, and aging on postural coordination and
control. First, two methods were used to evaluate postural coordination. A wavelet coherence approach was developed and applied to assess the level and pattern of coordination between pairs of joints (i.e., ankle-knee, ankle-trunk, and ankle-head). In addition, the uncontrolled manifold method was implemented for evaluation of potential whole-body coordination
control goals. Clear patterns of intermittent wavelet coherence were evident, indicating that joint coordination is intermittently executed. Both in-phase and anti-phase coherence were detected over frequencies of 2.5 – 4.0 Hz. Shoulder and head kinematics appeared more likely than the whole-body center of mass as
control goals for whole body coordination. Both aging and ankle muscle fatigue led to a reduction of joint coordination. Second, an intermittent sliding mode controller was developed to model quiet upright stance. In contrast to most previous postural controllers, which assume continuous
control, an intermittent controller was considered more consistent with recent evidence on muscle activity and the results of the first study on postural coordination. The sliding mode controller was able to accurately track kinematics and kinetics, and generated passive and active ankle torques comparable with previous results. Ankle fatigue led to an increase in active ankle torque especially among young adults and males. Third, a new method was developed to estimate passive and active mechanical properties at the ankle (e.g.,
stiffness and damping). This method was inspired from intermittent
control theory, and the earlier results noted. As opposed to conventional methods, this new method is computationally efficient and does not require external mechanical or sensory perturbations. The method yielded a ratio of passive to active ankle torques consistent with earlier evidence, and larger passive and active ankle torques among males and older adults. A post-fatigue increase of active ankle torque was estimated, especially among males and young adults. In addition to providing new analytical methods, the noted studies suggest that older adults have decreased joint coordination and increased ankle
stiffness. As a practical implication of this, fall…
Advisors/Committee Members: Nussbaum, Maury A. (committeechair), Agnew, Michael J. (committeechair), Madigan, Michael L. (committee member), Lockhart, Thurmon E. (committee member).
Subjects/Keywords: Postural Control; Joint Stiffness and Coordination; Localized Muscle Fatigue; Fall Prevention; Whole Body Coordination
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APA (6th Edition):
Zhang, H. B. (2013). Developing and Evaluating New Methods for Assessing Postural Control and Dynamics. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/19289
Chicago Manual of Style (16th Edition):
Zhang, Hong Bo. “Developing and Evaluating New Methods for Assessing Postural Control and Dynamics.” 2013. Doctoral Dissertation, Virginia Tech. Accessed January 28, 2021.
http://hdl.handle.net/10919/19289.
MLA Handbook (7th Edition):
Zhang, Hong Bo. “Developing and Evaluating New Methods for Assessing Postural Control and Dynamics.” 2013. Web. 28 Jan 2021.
Vancouver:
Zhang HB. Developing and Evaluating New Methods for Assessing Postural Control and Dynamics. [Internet] [Doctoral dissertation]. Virginia Tech; 2013. [cited 2021 Jan 28].
Available from: http://hdl.handle.net/10919/19289.
Council of Science Editors:
Zhang HB. Developing and Evaluating New Methods for Assessing Postural Control and Dynamics. [Doctoral Dissertation]. Virginia Tech; 2013. Available from: http://hdl.handle.net/10919/19289
Purdue University
16.
Sayed, Shehrin.
Performance-on-Demand MEMS (PODMEMS): Electrical Control of Effective Mass, Damping, and Stiffness.
Degree: MSECE, Electrical and Computer Engineering, 2013, Purdue University
URL: http://docs.lib.purdue.edu/open_access_theses/90
► We propose the use of electrostatic force feedback to control the stiffness, damping, or mass of MEMS. If feedback forces are proportional to sensed…
(more)
▼ We propose the use of electrostatic force feedback to
control the
stiffness, damping, or mass of MEMS. If feedback forces are proportional to sensed displacement, velocity, or acceleration of a MEMS proof mass, then feedback can be used to increase or decrease the apparent
stiffness, damping, and or mass of the MEMS. Such feedback can be used to compensate for process variations, packaging stress, thermal drift, viscous damping, etc. Prior efforts by others include position or velocity based feedback for modifying frequency, bandwidth, quality factor, or sensitivity of resonators. We present a means of quantitative
control of
stiffness, damping, and mass of MEMS to achieve performance on demand, which we call Performance-on-Demand MEMS (PODMEMS). Our comprehensive
control on effective parameters may enable two devices with different geometry to behave identically. This technology might enable a single PODMEMS to adjust its dynamic response depending on an application's requirements. We derive and study both steady-state and transient PODMEMS models that include feedback forces, circuit delay, and noise. We compare transient and steady-state results for verification. There exists cross-talk among effective parameters. Cross-talk in effective damping from electrical mass and
stiffness can decrease/increase the damping. The effective damping may become negative due to cross-talk, making the system unstable. The delayed feedback forces develop hysteresis in displacement, velocity, and acceleration and the width of hysteresis loop increases as the delay increases. Due to delayed feedback forces, the potential/kinetic energy show late or early minima/maxima and there are two minima/maxima throughout a cycle. Although potential energy and kinetic energy are affected by hysteresis of the feedback forces, the total energy is constant throughout a cycle. We have also simulated a test structure and found that frequency shift due to temperature variation can be reduced by a factor of ~2600 for our test case.
Advisors/Committee Members: Jason V. Clark, Jason V. Clark, Babak Ziaie, Dimitrios Peroulis, Jeffrey F. Rhoads.
Subjects/Keywords: effective mass; damping; stiffness; feedback control; performance tuning; podmems; process variation; thermal vibration; Electrical and Electronics; Mechanical Engineering
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APA ·
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APA (6th Edition):
Sayed, S. (2013). Performance-on-Demand MEMS (PODMEMS): Electrical Control of Effective Mass, Damping, and Stiffness. (Thesis). Purdue University. Retrieved from http://docs.lib.purdue.edu/open_access_theses/90
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Sayed, Shehrin. “Performance-on-Demand MEMS (PODMEMS): Electrical Control of Effective Mass, Damping, and Stiffness.” 2013. Thesis, Purdue University. Accessed January 28, 2021.
http://docs.lib.purdue.edu/open_access_theses/90.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Sayed, Shehrin. “Performance-on-Demand MEMS (PODMEMS): Electrical Control of Effective Mass, Damping, and Stiffness.” 2013. Web. 28 Jan 2021.
Vancouver:
Sayed S. Performance-on-Demand MEMS (PODMEMS): Electrical Control of Effective Mass, Damping, and Stiffness. [Internet] [Thesis]. Purdue University; 2013. [cited 2021 Jan 28].
Available from: http://docs.lib.purdue.edu/open_access_theses/90.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Sayed S. Performance-on-Demand MEMS (PODMEMS): Electrical Control of Effective Mass, Damping, and Stiffness. [Thesis]. Purdue University; 2013. Available from: http://docs.lib.purdue.edu/open_access_theses/90
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Univerzitet u Beogradu
17.
Mrdaković, Vladimir D., 1981-.
Neuromehanička kontrola izvođenja submaksimalnih
skokova.
Degree: Fakultet sporta i fizičkog vaspitanja, 2015, Univerzitet u Beogradu
URL: https://fedorabg.bg.ac.rs/fedora/get/o:9183/bdef:Content/get
► Fizičko vaspitanje i sport - Opšta motorika čoveka – Biomehanika i Motorna kontrola / Physical Education and Sport - Biomechanics and Motor Control
Kako se…
(more)
▼ Fizičko vaspitanje i sport - Opšta motorika čoveka
– Biomehanika i Motorna kontrola / Physical Education and Sport -
Biomechanics and Motor Control
Kako se većina skokova u trenažnim i takmičarskim
uslovima izvodi intenzitetom koji je manji od maksimalnog
(submaksimalni), neophodno je utvrditi koje su to neuromišićne i
biomehaničke varijable koje učestvuju u kontroli izvođenja skokova
submaksimalnim intenzitetom. Uže definisan cilj istraživanja
predstavlja ispitivanje kako se na promenu intenziteta izvođenja i
intenziteta opterećenja vertikalnih sunožnih skokova prilagođavaju
unapred programirane i fidbek aktivnosti centralnog nervnog
sistema, kao i određene biomehaničke varijable. Za potrebe
realizacije cilja istraživanja praćene su elektromiografske i
biomehaničke varijable u okviru dve eksperimentalne postavke. Prva
eksperimentalna postavka (EKS-1) sprovedena je sa petnaest
ispitanika i odnosila se na ispitivanje kontrole izvođenja
submaksimalnih vertikalnih sunožnih skokova nakon doskoka sa
platforme određene visine (DJ skokovi). Druga eksperimentalna
postavka (EKS-2) sprovedena je sa osam ispitanika i bila je
usmerena ka ispitivanju kontrole izvođenja submaksimalnih
vertikalnih skokova sa amortizacionom pripremom (CMJ skokovi). U
okviru EKS-1 ispitanici su izvodili DJ skokove sa različitih visina
platforme (20, 40 i 60 cm) i na različite visine odskoka (65, 80 i
95% od maksimalnog), dok su ispitanici u okviru EKS-2 izvodili CMJ
skokove na različite visine odskoka (65, 80 i 95% od maksimalnog).
Najbitniji rezultati i zaključci ove studije ukazuju na sledeće:
(1) mehanizmi unapred programirane aktivnosti nemaju značajan
uticaj na doziranje visine odskoka; (2) povećanje visine odskoka
značajno utiče na povećanje aktivacije većine mišića donjih
ekstremiteta tek u fazi otiskivanja od podloge, što ukazuje da
mehanizmi reprogramiranja i fidbek kontrole imaju značajan uticaj
na doziranje visine odskoka; (3) povećanje visine platforme je
dominantan faktor koji utiče na povećanje aktivacije većine mišića
donjih ekstremiteta tokom svih praćenih faza, gde je za fazu
preaktivacije i fazu u kojoj se javlja prvi mišićni odgovor nakon
kontakta sa podlogom nevažno kojim se intenzitetom izvodi odskok,
već je isključivo bitno sa koje visine platforme se izvodi doskok;
(4) ekstenzioni momenat u zglobu kuka je najvažnija biomehanička
varijabla koja doprinosi uvećanju visine odskoka kod DJ i CMJ
skoka.
Advisors/Committee Members: Ilić, Duško, 1965-.
Subjects/Keywords: electromyography; preactivation; feedback control;
motor program; stiffness; center of mass; joint moments; jump
height; drop height
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❌
APA ·
Chicago ·
MLA ·
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CSE |
Export
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Manager
APA (6th Edition):
Mrdaković, Vladimir D., 1. (2015). Neuromehanička kontrola izvođenja submaksimalnih
skokova. (Thesis). Univerzitet u Beogradu. Retrieved from https://fedorabg.bg.ac.rs/fedora/get/o:9183/bdef:Content/get
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Mrdaković, Vladimir D., 1981-. “Neuromehanička kontrola izvođenja submaksimalnih
skokova.” 2015. Thesis, Univerzitet u Beogradu. Accessed January 28, 2021.
https://fedorabg.bg.ac.rs/fedora/get/o:9183/bdef:Content/get.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Mrdaković, Vladimir D., 1981-. “Neuromehanička kontrola izvođenja submaksimalnih
skokova.” 2015. Web. 28 Jan 2021.
Vancouver:
Mrdaković, Vladimir D. 1. Neuromehanička kontrola izvođenja submaksimalnih
skokova. [Internet] [Thesis]. Univerzitet u Beogradu; 2015. [cited 2021 Jan 28].
Available from: https://fedorabg.bg.ac.rs/fedora/get/o:9183/bdef:Content/get.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Mrdaković, Vladimir D. 1. Neuromehanička kontrola izvođenja submaksimalnih
skokova. [Thesis]. Univerzitet u Beogradu; 2015. Available from: https://fedorabg.bg.ac.rs/fedora/get/o:9183/bdef:Content/get
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Rice University
18.
Sun, Chao.
Structural Vibration Control of Nonlinear Systems Using the Smart Tuned Mass Damper (STMD) and the Nonlinear Tuned Mass Damper (NTMD) in Parallel.
Degree: PhD, Engineering, 2013, Rice University
URL: http://hdl.handle.net/1911/77526
► Structural vibration control systems can be divided into four categories: 1) active control; 2) passive control; 3) semi-active control; and 4) hybrid control. It is…
(more)
▼ Structural vibration
control systems can be divided into four categories: 1) active
control; 2) passive
control; 3) semi-active
control; and 4) hybrid
control. It is well established that the semi-active
control can provide
control effect comparable to that of the active
control but requires orders of magnitude smaller external energy. In this regard, researchers in this field have proposed and developed many promising semi-active
control methodologies and devices, of which the semi-active or smart tuned mass damper (STMD) is very effective in reducing structural vibrations. In addition, adaptive-passive tuned mass damper (APTMD) which is tuned mechanically provides better reduction than the conventional passive TMD. In the present study, two kinds of TMDs: the smart tuned mass damper (STMD) which has variable frequency and variable damping ratio, and the adaptive passive tuned mass damper (APTMD) are investigated for the
control of both linear and nonlinear structures.
Vibration of nonlinear systems is characterized by multiple solution branches and instability, such as bifurcations (the jump phenomenon), and chaos. For a hardening Düffing oscillator subjected to harmonic excitations, a nonlinear tuned mass damper (NTMD) provides better and more robust
control effect than the linear TMD; however, the NTMD will result in high amplitude ''detached resonance" in the lower frequency region in the frequency response curve. To address this issue, a smart tuned mass damper (STMD) is connected to the primary Düffing system in parallel with an NTMD. It is found that through the introduction of the STMD, the structural response is attenuated significantly and the detached resonance branch becomes minimal. In addition, the combination of the STMD and the NTMD can attenuate the transient responses more effectively than a single STMD.
For the two degrees of freedom (DOF) system of the primary linear structure and an STMD, closed-form solutions are derived for the system under harmonic excitation and ground motions. The solutions for the dynamic system provide insight into the two DOF system: the variation of the damping ratio and the mass ratio can affect the attenuation through influencing the phase angle of the structure, the phase angle of the STMD, and the phase difference between the structure and the STMDs. As the mass ratio increases or the damping ratio decreases or both thereof, the phase difference θ
r approaches π/2 which corresponds to a maximum energy flow and dissipation, thereby attenuating the structural response more effectively.
To examine the effectiveness of the STMD for seismic protection, an STMD with variable damping coefficient and
stiffness is evaluated under seismic excitations. Variation of the damping ratio of the STMD is implemented through tracking the displacement of the STMD. If the tracked amplitude of the STMD is increasing, damping ratio of the STMD is set to zero; else it is set to an appropriate non-zero value.
Stiffness of the STMD is tuned through tracking…
Advisors/Committee Members: Nagarajaiah, Satish (advisor), Padgett, Jamie E. (committee member), Dick, Andrew J. (committee member).
Subjects/Keywords: Vibration control; Duffing system; Smart tuned mass damper; Adaptive tuned mass damper; Closed-form Solution; Adaptive passive stiffness device
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❌
APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sun, C. (2013). Structural Vibration Control of Nonlinear Systems Using the Smart Tuned Mass Damper (STMD) and the Nonlinear Tuned Mass Damper (NTMD) in Parallel. (Doctoral Dissertation). Rice University. Retrieved from http://hdl.handle.net/1911/77526
Chicago Manual of Style (16th Edition):
Sun, Chao. “Structural Vibration Control of Nonlinear Systems Using the Smart Tuned Mass Damper (STMD) and the Nonlinear Tuned Mass Damper (NTMD) in Parallel.” 2013. Doctoral Dissertation, Rice University. Accessed January 28, 2021.
http://hdl.handle.net/1911/77526.
MLA Handbook (7th Edition):
Sun, Chao. “Structural Vibration Control of Nonlinear Systems Using the Smart Tuned Mass Damper (STMD) and the Nonlinear Tuned Mass Damper (NTMD) in Parallel.” 2013. Web. 28 Jan 2021.
Vancouver:
Sun C. Structural Vibration Control of Nonlinear Systems Using the Smart Tuned Mass Damper (STMD) and the Nonlinear Tuned Mass Damper (NTMD) in Parallel. [Internet] [Doctoral dissertation]. Rice University; 2013. [cited 2021 Jan 28].
Available from: http://hdl.handle.net/1911/77526.
Council of Science Editors:
Sun C. Structural Vibration Control of Nonlinear Systems Using the Smart Tuned Mass Damper (STMD) and the Nonlinear Tuned Mass Damper (NTMD) in Parallel. [Doctoral Dissertation]. Rice University; 2013. Available from: http://hdl.handle.net/1911/77526
Brno University of Technology
19.
Minář, Petr.
Návrh konstrukce automatizovaného goniofotometru, polohovacího zařízení pro měření svítidel.: Design of goniophotometer construction for positioning of luminaires during measurement.
Degree: 2019, Brno University of Technology
URL: http://hdl.handle.net/11012/6186
► The main subject of this bachelor’s thesis is to design goniophotometer construction for positioning of luminaires during measurement. Firs part deals with description of general…
(more)
▼ The main
subject of this bachelor’s thesis is to design goniophotometer construction for positioning of luminaires during measurement. Firs part deals with description of general goniophotometer construction, their characteristic and methods, which are used for measuring. Second part deals with design of complete appliance including all-purpose chucking mechanism and drive, for automatic
control.
Advisors/Committee Members: Blecha, Petr (advisor), Škoda, Jan (referee).
Subjects/Keywords: Fotometrie; goniofotometr; upínací zařízení; tuhost rámu; automatizovaný pohon.; Photometry; goniophotometer; chucking mechanism; frame stiffness; automatic control drive.
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APA ·
Chicago ·
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Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Minář, P. (2019). Návrh konstrukce automatizovaného goniofotometru, polohovacího zařízení pro měření svítidel.: Design of goniophotometer construction for positioning of luminaires during measurement. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/6186
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Minář, Petr. “Návrh konstrukce automatizovaného goniofotometru, polohovacího zařízení pro měření svítidel.: Design of goniophotometer construction for positioning of luminaires during measurement.” 2019. Thesis, Brno University of Technology. Accessed January 28, 2021.
http://hdl.handle.net/11012/6186.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Minář, Petr. “Návrh konstrukce automatizovaného goniofotometru, polohovacího zařízení pro měření svítidel.: Design of goniophotometer construction for positioning of luminaires during measurement.” 2019. Web. 28 Jan 2021.
Vancouver:
Minář P. Návrh konstrukce automatizovaného goniofotometru, polohovacího zařízení pro měření svítidel.: Design of goniophotometer construction for positioning of luminaires during measurement. [Internet] [Thesis]. Brno University of Technology; 2019. [cited 2021 Jan 28].
Available from: http://hdl.handle.net/11012/6186.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Minář P. Návrh konstrukce automatizovaného goniofotometru, polohovacího zařízení pro měření svítidel.: Design of goniophotometer construction for positioning of luminaires during measurement. [Thesis]. Brno University of Technology; 2019. Available from: http://hdl.handle.net/11012/6186
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
20.
LI RENJUN.
Improving force control through end-effector vibration reduction and variable stiffness joint design.
Degree: 2014, National University of Singapore
URL: http://scholarbank.nus.edu.sg/handle/10635/77760
Subjects/Keywords: force control; series macro mini; variable stiffness actuator
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❌
APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
RENJUN, L. (2014). Improving force control through end-effector vibration reduction and variable stiffness joint design. (Thesis). National University of Singapore. Retrieved from http://scholarbank.nus.edu.sg/handle/10635/77760
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
RENJUN, LI. “Improving force control through end-effector vibration reduction and variable stiffness joint design.” 2014. Thesis, National University of Singapore. Accessed January 28, 2021.
http://scholarbank.nus.edu.sg/handle/10635/77760.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
RENJUN, LI. “Improving force control through end-effector vibration reduction and variable stiffness joint design.” 2014. Web. 28 Jan 2021.
Vancouver:
RENJUN L. Improving force control through end-effector vibration reduction and variable stiffness joint design. [Internet] [Thesis]. National University of Singapore; 2014. [cited 2021 Jan 28].
Available from: http://scholarbank.nus.edu.sg/handle/10635/77760.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
RENJUN L. Improving force control through end-effector vibration reduction and variable stiffness joint design. [Thesis]. National University of Singapore; 2014. Available from: http://scholarbank.nus.edu.sg/handle/10635/77760
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
21.
Visser, L.C.
Variable Stiffness Actuators: Modeling, Control, and Application to Compliant Bipedal Walking.
Degree: 2013, Centre for Telematics and Information Technology (CTIT)
URL: https://research.utwente.nl/en/publications/variable-stiffness-actuators(4f9a948b-ffac-45b6-a8ca-96e9c02cab02).html
;
urn:nbn:nl:ui:28-4f9a948b-ffac-45b6-a8ca-96e9c02cab02
;
4f9a948b-ffac-45b6-a8ca-96e9c02cab02
;
10.3990/1.9789036535519
;
urn:isbn:978-90-365-3551-9
;
urn:nbn:nl:ui:28-4f9a948b-ffac-45b6-a8ca-96e9c02cab02
;
https://research.utwente.nl/en/publications/variable-stiffness-actuators(4f9a948b-ffac-45b6-a8ca-96e9c02cab02).html
► Robots are traditionally used in factory environments, where they perform tasks with high precision and speed. This kind of robots is designed to have a…
(more)
▼ Robots are traditionally used in factory environments, where they perform tasks with high precision and speed. This kind of robots is designed to have a high mechanical
stiffness and with powerful motors, so that the required precision and speed can be achieved. However, such designs are inherently unsafe, and therefore these robots are separated from the factory workers. In order to have robots safely interact with humans, they need to meet new requirements in terms of safety and interaction. Actuators with variable
stiffness are characterized by the property that their apparent output
stiffness can be varied. This is generally realized by incorporating a number of elastic elements in the design. A number of internal degrees of freedom are then used to regulate how these elastic elements are perceived at the actuator output. A robot equipped with such actuators can thus adapt its impedance to levels suitable for a given task and environment. Furthermore, the elastic elements can be used to temporarily store energy, which can be beneficial for increasing the energy-efficiency of such robots. This dissertation explores the designs and applications of actuators with variable
stiffness, with a focus on their energetic behavior. For this purpose a generic model has been developed, which enables the analysis for the power flows between the internal elastic elements and the environment. This analysis provides insight in the efficiency of the actuator by visualizing how externally supplied energy can be temporarily stored and reused. These insights are at the basis of two new
control algorithms, which aim and minimizing the energy consumption of the actuator. Finally, the application of variable
stiffness to bipedal locomotion is investigated. It is shown that the application of variable
stiffness can have a positive influence on the robustness and efficiency of bipedal locomotion.
Advisors/Committee Members: Stramigioli, Stefano, Carloni, Raffaella.
Subjects/Keywords: Modeling; EWI-24348; Variable Stiffness Actuators; compliant walking; Control
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APA ·
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Export
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Manager
APA (6th Edition):
Visser, L. C. (2013). Variable Stiffness Actuators: Modeling, Control, and Application to Compliant Bipedal Walking. (Doctoral Dissertation). Centre for Telematics and Information Technology (CTIT). Retrieved from https://research.utwente.nl/en/publications/variable-stiffness-actuators(4f9a948b-ffac-45b6-a8ca-96e9c02cab02).html ; urn:nbn:nl:ui:28-4f9a948b-ffac-45b6-a8ca-96e9c02cab02 ; 4f9a948b-ffac-45b6-a8ca-96e9c02cab02 ; 10.3990/1.9789036535519 ; urn:isbn:978-90-365-3551-9 ; urn:nbn:nl:ui:28-4f9a948b-ffac-45b6-a8ca-96e9c02cab02 ; https://research.utwente.nl/en/publications/variable-stiffness-actuators(4f9a948b-ffac-45b6-a8ca-96e9c02cab02).html
Chicago Manual of Style (16th Edition):
Visser, L C. “Variable Stiffness Actuators: Modeling, Control, and Application to Compliant Bipedal Walking.” 2013. Doctoral Dissertation, Centre for Telematics and Information Technology (CTIT). Accessed January 28, 2021.
https://research.utwente.nl/en/publications/variable-stiffness-actuators(4f9a948b-ffac-45b6-a8ca-96e9c02cab02).html ; urn:nbn:nl:ui:28-4f9a948b-ffac-45b6-a8ca-96e9c02cab02 ; 4f9a948b-ffac-45b6-a8ca-96e9c02cab02 ; 10.3990/1.9789036535519 ; urn:isbn:978-90-365-3551-9 ; urn:nbn:nl:ui:28-4f9a948b-ffac-45b6-a8ca-96e9c02cab02 ; https://research.utwente.nl/en/publications/variable-stiffness-actuators(4f9a948b-ffac-45b6-a8ca-96e9c02cab02).html.
MLA Handbook (7th Edition):
Visser, L C. “Variable Stiffness Actuators: Modeling, Control, and Application to Compliant Bipedal Walking.” 2013. Web. 28 Jan 2021.
Vancouver:
Visser LC. Variable Stiffness Actuators: Modeling, Control, and Application to Compliant Bipedal Walking. [Internet] [Doctoral dissertation]. Centre for Telematics and Information Technology (CTIT); 2013. [cited 2021 Jan 28].
Available from: https://research.utwente.nl/en/publications/variable-stiffness-actuators(4f9a948b-ffac-45b6-a8ca-96e9c02cab02).html ; urn:nbn:nl:ui:28-4f9a948b-ffac-45b6-a8ca-96e9c02cab02 ; 4f9a948b-ffac-45b6-a8ca-96e9c02cab02 ; 10.3990/1.9789036535519 ; urn:isbn:978-90-365-3551-9 ; urn:nbn:nl:ui:28-4f9a948b-ffac-45b6-a8ca-96e9c02cab02 ; https://research.utwente.nl/en/publications/variable-stiffness-actuators(4f9a948b-ffac-45b6-a8ca-96e9c02cab02).html.
Council of Science Editors:
Visser LC. Variable Stiffness Actuators: Modeling, Control, and Application to Compliant Bipedal Walking. [Doctoral Dissertation]. Centre for Telematics and Information Technology (CTIT); 2013. Available from: https://research.utwente.nl/en/publications/variable-stiffness-actuators(4f9a948b-ffac-45b6-a8ca-96e9c02cab02).html ; urn:nbn:nl:ui:28-4f9a948b-ffac-45b6-a8ca-96e9c02cab02 ; 4f9a948b-ffac-45b6-a8ca-96e9c02cab02 ; 10.3990/1.9789036535519 ; urn:isbn:978-90-365-3551-9 ; urn:nbn:nl:ui:28-4f9a948b-ffac-45b6-a8ca-96e9c02cab02 ; https://research.utwente.nl/en/publications/variable-stiffness-actuators(4f9a948b-ffac-45b6-a8ca-96e9c02cab02).html
Brno University of Technology
22.
Suza, Dominik.
Dočasné zesilování silničních mostů: Temporary strengthening of road bridges.
Degree: 2018, Brno University of Technology
URL: http://hdl.handle.net/11012/136999
► Bridge strengthening is frequently associated with costly, long-term reconstruction. In some cases the bridge load capacity is sufficient for standard traffic, but requirements for an…
(more)
▼ Bridge strengthening is frequently associated with costly, long-term reconstruction. In some cases the bridge load capacity is sufficient for standard traffic, but requirements for an extremely heavy vehicle can exceed the maximal bridge load capacity. These vehicles normally weigh hundreds of tons. Moreover, well-known bridge strengthening technologies are not efficient and economical for this special load case. This doctoral thesis presents a short-term bridge strengthening method using a temporary support structure for the assistance of the existing bridge carrying structure. Although this strengthening method is rather old, it is rarely known. Approaches from 1980, are still often used, rely on simplified principles and approximation models. This approximation causes restricted efficiency of the strengthening system and creates a mathematical model that is not necessarily safe. The introduced new short-term bridge strengthening theory is based on monitoring of real bridge structures and temporary support structures during the crossing of extremely heavy vehicles. A mathematical model, which represents behaviour of real structures suitable, is introduced. The major effects, which have the greatest influence on this strengthening method are discussed. Further more a safety hydraulic element invented at Brno University of Technology, which can be used with the strengthening system is shown. The application of this system ensures required boundary conditions and therefore it guarantees the proper usage of the strengthening system.
Advisors/Committee Members: Klusáček, Ladislav (advisor), Kaplan,, Věroslav (referee), Pukl,, Radomír (referee).
Subjects/Keywords: Zesilování; Krátkodobé zesílení; podpírání; zesilování mostů; podpěrný systém; řiditelná tuhost; Strengthening; short-time strengthening; supporting; bridge strengthening; supporting structure; control stiffness
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APA (6th Edition):
Suza, D. (2018). Dočasné zesilování silničních mostů: Temporary strengthening of road bridges. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/136999
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Suza, Dominik. “Dočasné zesilování silničních mostů: Temporary strengthening of road bridges.” 2018. Thesis, Brno University of Technology. Accessed January 28, 2021.
http://hdl.handle.net/11012/136999.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Suza, Dominik. “Dočasné zesilování silničních mostů: Temporary strengthening of road bridges.” 2018. Web. 28 Jan 2021.
Vancouver:
Suza D. Dočasné zesilování silničních mostů: Temporary strengthening of road bridges. [Internet] [Thesis]. Brno University of Technology; 2018. [cited 2021 Jan 28].
Available from: http://hdl.handle.net/11012/136999.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Suza D. Dočasné zesilování silničních mostů: Temporary strengthening of road bridges. [Thesis]. Brno University of Technology; 2018. Available from: http://hdl.handle.net/11012/136999
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Delft University of Technology
23.
Nijsse, G.J.P.
Linear Motion Systems. A Modular Approach for Improved Straightness Performance.
Degree: 2001, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485
;
urn:NBN:nl:ui:24-uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485
;
urn:NBN:nl:ui:24-uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485
;
http://resolver.tudelft.nl/uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485
► This thesis deals with straight motion systems. A modular approach has been applied in order to find ways to improve the performance. The main performance…
(more)
▼ This thesis deals with straight motion systems. A modular approach has been applied in order to find ways to improve the performance. The main performance parameters that are considered are position accuracy, repeatability and, to a lesser extent, cost. Because of the increasing requirements to positioning systems, concerning accuracy, repeatability and velocity, it becomes more and more difficult to meet these requirements when using merely mechanical means. The errors in position occurring as a result of e.g. external forces, wear or thermal expansion, are the reason that open-loop straight motion systems can only operate in the sub-micrometer range when very strict conditions are applied. When the required accuracy becomes smaller than the manufacturing tolerances achievable, active compensation of errors becomes indispensable. On the other hand, by the application of active error compensation, the requirements to the manufacturing accuracy can decrease. By means of this feedback of straightness errors, the problems and bottlenecks shift from the mechanical domain towards the electronics and
control engineering domain, where they are better solvable. The eventual performance of a feedback controlled system is not limited any more by fabrication tolerances, bearing properties, thermal influences or external loads, but is mainly limited by the resolution of the sensor applied, and by the dynamical behaviour of the mechanical system. When aiming at a position accuracy in the sub-micrometer range, also vibration problems become important. Therefor, a completely different approach has been applied. Instead of aiming for the highest possible open-loop
stiffness of the positioning system relative to the ground, an actuator
stiffness equal to zero is proposed. The zero
stiffness bearing results in a decoupling of the position, while preserving the force coupling to the world. This means that the position of such an object (e.g. a specimen holder), supported by a zero
stiffness bearing, may be coupled to the position of another object (e.g. a lens on which no external forces are allowed) by means of a
control loop, resulting in a virtual
stiffness relative to each other. The forces, needed for positioning the moving object, cause a reaction force on the world, while the vibrations (position errors) of the world do not influence the positioning accuracy of that object. This concept offers possibilities in the design of precision positioning systems, where otherwise vibrations from the outer world would have a too large disturbing influence. Within the scope of this research on zero
stiffness actuators, a permanent magnetic bearing element has been designed and built, which is able to generate a static bearing force that is without mechanical contact, without
stiffness and without power consumption. The permanent magnetic zero
stiffness bearing principle has been patented in the Netherlands; an international patent application is pending.
Advisors/Committee Members: Van Beek, H.F..
Subjects/Keywords: straight motion; feedback control; zero stiffness actuators
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APA ·
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MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Nijsse, G. J. P. (2001). Linear Motion Systems. A Modular Approach for Improved Straightness Performance. (Doctoral Dissertation). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485 ; urn:NBN:nl:ui:24-uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485 ; urn:NBN:nl:ui:24-uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485 ; http://resolver.tudelft.nl/uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485
Chicago Manual of Style (16th Edition):
Nijsse, G J P. “Linear Motion Systems. A Modular Approach for Improved Straightness Performance.” 2001. Doctoral Dissertation, Delft University of Technology. Accessed January 28, 2021.
http://resolver.tudelft.nl/uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485 ; urn:NBN:nl:ui:24-uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485 ; urn:NBN:nl:ui:24-uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485 ; http://resolver.tudelft.nl/uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485.
MLA Handbook (7th Edition):
Nijsse, G J P. “Linear Motion Systems. A Modular Approach for Improved Straightness Performance.” 2001. Web. 28 Jan 2021.
Vancouver:
Nijsse GJP. Linear Motion Systems. A Modular Approach for Improved Straightness Performance. [Internet] [Doctoral dissertation]. Delft University of Technology; 2001. [cited 2021 Jan 28].
Available from: http://resolver.tudelft.nl/uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485 ; urn:NBN:nl:ui:24-uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485 ; urn:NBN:nl:ui:24-uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485 ; http://resolver.tudelft.nl/uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485.
Council of Science Editors:
Nijsse GJP. Linear Motion Systems. A Modular Approach for Improved Straightness Performance. [Doctoral Dissertation]. Delft University of Technology; 2001. Available from: http://resolver.tudelft.nl/uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485 ; urn:NBN:nl:ui:24-uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485 ; urn:NBN:nl:ui:24-uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485 ; http://resolver.tudelft.nl/uuid:d0ee41a2-2b65-4c7d-b54c-1cfafac63485
24.
Behrooz, Majid.
A Controllable Flexible Micropump and a Semi-Active Vibration Absorber Using Magnetorheological Elastomers.
Degree: 2015, University of Nevada – Reno
URL: http://hdl.handle.net/11714/2540
► This study is focused on magneto-fluid-solid interaction analysis of a soft magnetorheological elastomer (MRE) controllable flexible micropump. In addition, material characterizations of MRE, modeling, fabrication…
(more)
▼ This study is focused on magneto-fluid-solid interaction analysis of a soft magnetorheological elastomer (MRE) controllable flexible micropump. In addition, material characterizations of MRE, modeling, fabrication and testing of a MRE-based vibration absorber system are investigated.Theoretical modeling and analysis of a controllable flexible magnetically-actuated fluid transport system (CFMFTS) is presented. For the first time, soft magnetorheological elastomer (MRE) is proposed as an actuation element in a fluid transport system (micropump). The flexible micropump can propel fluid under a fluctuating magnetic field. Magnetic-fluid-solid interaction analysis is performed to determine deflection in the solid domain and velocity of the fluid under a magnetic field. The effects of key material and geometric system parameters are examined on the micropump performance. Two- and three-dimensional analyses are performed to model the asymmetric deflection of the channel under a magnetic field. It is successfully demonstrated that the proposed system can propel the fluid in one direction.In addition, a novel semi-active variable
stiffness and damping absorber (VSDA) is modeled, built and tested. Magnetically induced mechanical properties of MRE and their controllability are investigated by quasi-static and dynamic experiments. The VSDA is modeled, using springs, dashpots and the Bouc-Wen hysteresis element, fabricated and implemented in a scaled building to assess performance. Experiments are performed on a single VSDA, integrated system of four VSDAs, and a scaled building supported by four VSDAs. To demonstrate feasibility, a scaled, two-story building is constructed and installed on a shake table supported by four prototype VSDAs. The properties of VSDAs are regulated in real time by varying the applied magnetic field through the controller. A scaled earthquake excitation is applied to the system, and the vibration mode is controlled by a Lyapunov-based
control strategy. The
control system is used to
control displacement and acceleration of the floors. Results demonstrate that the proposed VSDA significantly reduces acceleration and relative displacement of the structure.
Advisors/Committee Members: Gordaninejad, Faramarz (advisor), Pinskey, Mark A (committee member), Geiger, Emil J (committee member), Ryan, Keri L (committee member), Shan, Wanliang (committee member).
Subjects/Keywords: Fluid Transport System; Micropump; Semi-Active Control; Soft Magnetorheological Elastomer; Variable Stiffness and Damping; Vibration Absorber
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Behrooz, M. (2015). A Controllable Flexible Micropump and a Semi-Active Vibration Absorber Using Magnetorheological Elastomers. (Thesis). University of Nevada – Reno. Retrieved from http://hdl.handle.net/11714/2540
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Behrooz, Majid. “A Controllable Flexible Micropump and a Semi-Active Vibration Absorber Using Magnetorheological Elastomers.” 2015. Thesis, University of Nevada – Reno. Accessed January 28, 2021.
http://hdl.handle.net/11714/2540.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Behrooz, Majid. “A Controllable Flexible Micropump and a Semi-Active Vibration Absorber Using Magnetorheological Elastomers.” 2015. Web. 28 Jan 2021.
Vancouver:
Behrooz M. A Controllable Flexible Micropump and a Semi-Active Vibration Absorber Using Magnetorheological Elastomers. [Internet] [Thesis]. University of Nevada – Reno; 2015. [cited 2021 Jan 28].
Available from: http://hdl.handle.net/11714/2540.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Behrooz M. A Controllable Flexible Micropump and a Semi-Active Vibration Absorber Using Magnetorheological Elastomers. [Thesis]. University of Nevada – Reno; 2015. Available from: http://hdl.handle.net/11714/2540
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Vrije Universiteit Amsterdam
25.
Kistemaker, D.A.
Control of Fast Goal-Directed Arm Movements : a critical evaluation of the equilibrium point hypothesis
.
Degree: 2006, Vrije Universiteit Amsterdam
URL: http://hdl.handle.net/1871/9817
► Controle van snelle doelgerichte armbewegingen; een kritische evaluatie van de equilibrium punt hypothese Een belangrijke klasse van theorieën over hoe bewegingen worden gestuurd is gebaseerd…
(more)
▼ Controle van snelle doelgerichte armbewegingen; een kritische evaluatie van de equilibrium punt hypothese
Een belangrijke klasse van theorieën over hoe bewegingen worden gestuurd is gebaseerd op de equilibriumpunt (EP)-hypothese. Deze hypothese kan het best worden uitgelegd aan de hand van sturing van één enkel gewricht. Het idee is dat het centrale zenuwstelsel (CZS) in staat is om evenwichtsposities in te stellen. Dit zijn posities van het gewricht waarvoor geldt dat het netto-moment van alle spieren (die een moment leveren rond dat gewricht) gelijk is aan nul. In een variant van de EP-hypothese, bekend onder de naam a-model, wordt verondersteld dat het CZS in staat is om voor elke gewenste positie van het gewricht in het fysiologisch bewegingsbereik de open-loop spierstimulaties (d.w.z. zonder bijdrage van feedback) zodanig in te stellen dat het netto-moment van alle spieren rond dat gewricht in de gewenste positie gelijk is aan nul. Deze positie wordt het EP genoemd. Een EP is stabiel wanneer een uitwijking uit het EP resulteert in een moment dat, in afwezigheid van externe krachten, het gewricht terugdrijft naar de EP. Wanneer een nieuw EP wordt ingesteld, is het systeem niet langer in evenwicht en zal het naar het nieuw ingestelde EP gaan bewegen. Kort gesteld veronderstelt het a-model dat bewegingen worden gestuurd door verandering van het ingestelde open-loop EP. Een andere variant is het ?-model. Hierin wordt verondersteld dat het CZS drempelwaarden voor activatie van spieren (?) kan instellen. Deze drempelwaarde kan worden gezien als de gewenste spierlengte. De activatie van elke spier hangt af van het verschil tussen de gewenste spierlengte en de feedback over de werkelijke spierlengte gemeten door middel van spierspoelen: is een spier langer dan de gewenste lengte, dan zal deze meer geactiveerd worden, is een spier korter dan de gewenste lengte, dan zal deze minder geactiveerd worden. De ?’s van alle spieren die over een bepaald gewricht lopen kunnen zodanig ingesteld worden dat deze overeenkomen met de lengten van de spieren in de gewenste positie, het EP. In afwezigheid van externe krachten zullen de verschillen tussen de ingestelde ?’s en de werkelijke spierlengten het gewricht naar het ingestelde EP drijven (alleen in het EP zijn de ingestelde spierlengten gelijk aan de werkelijke spierlengten en zal de stimulatie nul zijn).
Het aantrekkelijke van EP-hypothese is dat EP-sturing geen berekeningen vereist om het zogenaamde ‘inverse dynamica’-probleem op te lossen. De spierkrachten, of spierstimulatiepatronen, nodig voor het uitvoeren van een gewenste beweging worden niet door het CZS uitgerekend (bijvoorbeeld aan de hand van een intern model), maar treden op als gevolg van de uitwijking uit het ingestelde EP. Tegenwoordig wordt er echter sterk getwijfeld aan de geschiktheid van de EP-hypothese voor de sturing van snelle mono-articulaire bewegingen. Het belangrijkste tegenargument is dat de stijfheid van het (aangestuurde) spierskeletstelsel te laag zou zijn om ‘simpele’ EP-trajecten (d.w.z. een…
Subjects/Keywords: Control of fast goal-directed arm movements;
force-length relationship;
muscle stiffness;
joint stiffness;
intermittent control
Record Details
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Record Details
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« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kistemaker, D. A. (2006). Control of Fast Goal-Directed Arm Movements : a critical evaluation of the equilibrium point hypothesis
. (Doctoral Dissertation). Vrije Universiteit Amsterdam. Retrieved from http://hdl.handle.net/1871/9817
Chicago Manual of Style (16th Edition):
Kistemaker, D A. “Control of Fast Goal-Directed Arm Movements : a critical evaluation of the equilibrium point hypothesis
.” 2006. Doctoral Dissertation, Vrije Universiteit Amsterdam. Accessed January 28, 2021.
http://hdl.handle.net/1871/9817.
MLA Handbook (7th Edition):
Kistemaker, D A. “Control of Fast Goal-Directed Arm Movements : a critical evaluation of the equilibrium point hypothesis
.” 2006. Web. 28 Jan 2021.
Vancouver:
Kistemaker DA. Control of Fast Goal-Directed Arm Movements : a critical evaluation of the equilibrium point hypothesis
. [Internet] [Doctoral dissertation]. Vrije Universiteit Amsterdam; 2006. [cited 2021 Jan 28].
Available from: http://hdl.handle.net/1871/9817.
Council of Science Editors:
Kistemaker DA. Control of Fast Goal-Directed Arm Movements : a critical evaluation of the equilibrium point hypothesis
. [Doctoral Dissertation]. Vrije Universiteit Amsterdam; 2006. Available from: http://hdl.handle.net/1871/9817
Penn State University
26.
Lotfi Gaskarimahalle, Amir.
VIBRATION CONTROL OF DISTRIBUTED PARAMETER SYSTEMS
AND FLUIDIC FLEXIBLE MATRIX COMPOSITES
.
Degree: 2009, Penn State University
URL: https://submit-etda.libraries.psu.edu/catalog/10098
► Vibration degrades the performance of many mechanical systems, reducing the quality of manufactured products, producing noise, introducing fatigue in mechanical compo- nents, and generating an…
(more)
▼ Vibration degrades the performance of many mechanical systems, reducing the quality
of manufactured products, producing noise, introducing fatigue in mechanical compo-
nents, and generating an uncomfortable environment for passengers. Vibration
control
is categorized as: active, passive, semi-active or hybrid, based on the power consumption
of the
control system and feedback or feedforward based on whether sensing is used to
control vibration. In this thesis, we study input shaping
control of Distributed Parame-
ter Systems (DPS) and passive and semi-active vibration
control using Fluidic Flexible
Matrix Composites (F2MC).
First, we extend input shaping
control to one dimensional continua. Unlike discrete
systems where the input is shaped only in the temporal domain, temporal and spatial
input shaping can produce zero residual vibration in setpoint position
control of distrib-
uted strings and beams. For collocated and noncollocated boundary
control of strings
and domain
control of strings and pinned beams, the response to step inputs is solved
in closed form using delays. For a clamped beam model, a closed form in…nite modal
series is used. The boundary controlled string can be setpoint regulated using two-pulse
Zero Vibration (ZV) and three-pulse Zero Vibration and Derivative (ZVD) shapers but
ZVD is not more robust to parameter variations than ZV, a unique characteristic of
second-order PDE systems. Noncollocated ZV and ZVD boundary
control enables rigid
body translation of a string with zero residual vibration. Domain controlled strings and
pinned beams with spatial input distributions that satisfy certain orthogonality condi-
tions (e.g. midspan point load or uniformly distributed load) can be setpoint regulated
with shaped inputs. For the cantilevered beam, modal shaping of the input distribution
and ZV or ZVD temporal shaping drives the tip to the desired position with zero residual
vibration.
A command shaping approach in vibration
control using F2MC tubes as variable
sti¤ness structures is studied in the third chapter. The apparent sti¤ness of F2MC tubes can be changed using a variable ori…ce valve. With …ber reinforcement, the volume inside
the tube may change with external load. With an open valve, the liquid is free to move
in or out of the tube, so the apparent sti¤ness does not change. When the valve is closed,
the high bulk modulus liquid is con…ned, which resists the volume change and causes the
apparent sti¤ness of the tube to increase. The equations of motion of an F2MC-mass
system is derived using a 3-D elasticity model and the energy method. A reduced order
model is then developed for fully-open and fully-closed valves. A Skyhook
control that
cycles the valve between open and closed, asymptotically decays the vibration. A Zero
Vibration (ZV) Sti¤ness Shaping technique is introduced to suppress the vibration in
…nite time. A sensitivity analysis of the ZV Sti¤ness Shaper studies the robustness to
parametric uncertainties.
We also investigate passive and semi-active vibration
control using F2MC…
Advisors/Committee Members: Christopher Rahn, Dissertation Advisor/Co-Advisor, Christopher Rahn, Committee Chair/Co-Chair, Alok Sinha, Committee Member, Qian Wang, Committee Member, George A Lesieutre, Committee Member.
Subjects/Keywords: Semi-active Control; Tuned Vibration Absorbers; Variable Stiffness Systems; Input Shaping; Vibration Control
Record Details
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lotfi Gaskarimahalle, A. (2009). VIBRATION CONTROL OF DISTRIBUTED PARAMETER SYSTEMS
AND FLUIDIC FLEXIBLE MATRIX COMPOSITES
. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/10098
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Lotfi Gaskarimahalle, Amir. “VIBRATION CONTROL OF DISTRIBUTED PARAMETER SYSTEMS
AND FLUIDIC FLEXIBLE MATRIX COMPOSITES
.” 2009. Thesis, Penn State University. Accessed January 28, 2021.
https://submit-etda.libraries.psu.edu/catalog/10098.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Lotfi Gaskarimahalle, Amir. “VIBRATION CONTROL OF DISTRIBUTED PARAMETER SYSTEMS
AND FLUIDIC FLEXIBLE MATRIX COMPOSITES
.” 2009. Web. 28 Jan 2021.
Vancouver:
Lotfi Gaskarimahalle A. VIBRATION CONTROL OF DISTRIBUTED PARAMETER SYSTEMS
AND FLUIDIC FLEXIBLE MATRIX COMPOSITES
. [Internet] [Thesis]. Penn State University; 2009. [cited 2021 Jan 28].
Available from: https://submit-etda.libraries.psu.edu/catalog/10098.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Lotfi Gaskarimahalle A. VIBRATION CONTROL OF DISTRIBUTED PARAMETER SYSTEMS
AND FLUIDIC FLEXIBLE MATRIX COMPOSITES
. [Thesis]. Penn State University; 2009. Available from: https://submit-etda.libraries.psu.edu/catalog/10098
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
27.
Andrecioli, Ricardo.
Grasped Object Detection for Adaptive Control of a
Prosthetic Hand.
Degree: MS, Mechanical Engineering, 2013, University of Akron
URL: http://rave.ohiolink.edu/etdc/view?acc_num=akron1364481779
► Unfortunately, statistical analyses of amputee data shows an increase of the population with upper limb losses either by trauma or birth congenital defects. Several prosthesis…
(more)
▼ Unfortunately, statistical analyses of amputee data
shows an increase of the population with upper limb losses either
by trauma or birth congenital defects. Several prosthesis options
are commercially available, including electric powered prostheses.
A review of surveys for upper limb prosthesis users have indicated
improvement opportunities in the prosthesis design as well as
improved functionality and controls. After review of literature, a
PID sliding mode position controller and an adaptive PID sliding
mode controller are presented for a prosthetic hand. The adaptive
controller smoothly modulates the gains based on the detected
stiffness of the grasped object. Three main
control strategies will
be compared: PID force
control, sliding mode position and hybrid
sliding mode force-position controllers. For each
control option,
an adaptive version will also be tested via benchtop experiments.
In order to evaluate the performance of each controller under
several grasping circumstances, a special manipulandum was designed
to provide variable linear and nonlinear
stiffness behavior, then
each controller was then evaluated according to an experiment plan.
The results from benchtop experiments indicate statistically
significant improvements such as improved tracking response and
reduced steady state error in the system response when using the
adaptive controller for all three
control cases considered. When
comparing Force versus Position versus Hybrid Force-Position
control, the latter when equipped of the adaptation method has
presented the best results.Preliminary amputee experiments were
also conducted using the adaptive hybrid force-position controller
in comparison to the constant gain controller as well as the
amputees’ current prostheses for daily use. The results of these
experiments show that the adaptive hybrid force-position sliding
mode controller enabled the amputees to smoothly handle the
manipulandum without breaking it.
Advisors/Committee Members: Engeberg, Erik (Advisor).
Subjects/Keywords: Biomechanics; Mechanical Engineering; Powered upper limb prosthesis; adaptive control; nonlinear control; robust control; stiffness control; stiffness detection.
…Force Control, PID gains vs. stiffness comparison by controller. ........................51… …62
47:
Position Control, PID gains vs. stiffness comparison by controller… …controller. .......83
79:
Force-Position Control, PID gains vs. stiffness comparison by… …position control and impedance or stiffness control (Chan, et al., 1991).
In this… …a flexible robot is in contact with its
environment and therefore stiffness control has…
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APA (6th Edition):
Andrecioli, R. (2013). Grasped Object Detection for Adaptive Control of a
Prosthetic Hand. (Masters Thesis). University of Akron. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=akron1364481779
Chicago Manual of Style (16th Edition):
Andrecioli, Ricardo. “Grasped Object Detection for Adaptive Control of a
Prosthetic Hand.” 2013. Masters Thesis, University of Akron. Accessed January 28, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=akron1364481779.
MLA Handbook (7th Edition):
Andrecioli, Ricardo. “Grasped Object Detection for Adaptive Control of a
Prosthetic Hand.” 2013. Web. 28 Jan 2021.
Vancouver:
Andrecioli R. Grasped Object Detection for Adaptive Control of a
Prosthetic Hand. [Internet] [Masters thesis]. University of Akron; 2013. [cited 2021 Jan 28].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=akron1364481779.
Council of Science Editors:
Andrecioli R. Grasped Object Detection for Adaptive Control of a
Prosthetic Hand. [Masters Thesis]. University of Akron; 2013. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=akron1364481779
University of Florida
28.
Van Etten, Nathaniel.
Effect of Environment on the Stiffness of Carbon Fiber Reinforced Polymer Repaired Concrete.
Degree: M.E., Civil Engineering - Civil and Coastal Engineering, 2008, University of Florida
URL: https://ufdc.ufl.edu/UFE0022708
► The use of carbon fiber reinforced polymer (CFRP) composites for repair and strengthening of concrete has been become increasingly popular in recent years. In the…
(more)
▼ The use of carbon fiber reinforced polymer (CFRP) composites for repair and strengthening of concrete has been become increasingly popular in recent years. In the past, research has been conducted to evaluate the mechanical properties of CFRP and its effectiveness as reinforcement. More recently, research has focused on the durability of CFRP on concrete. Unfortunately, the majority of durability research conducted on CFRP has focused on strength while the effects of moisture on
stiffness have remained relatively ignored. The goal of the research reported in this thesis was to investigate how the
stiffness properties of CFRP reinforced concrete beams are altered due to moisture immersion. Slotted beam specimens reinforced with CFRP composite strips were placed in exposure tanks created to provide full immersion in water at elevated temperatures of 30?C, 40?C, 50?C and 60?C. The effects of tidal exposure on
stiffness on CFRP reinforced beams were also investigated by placing beam specimens on bridge fenders found in Crescent Beach, FL. After immersion durations of 6, 12, and 18 months a group of CFRP specimens were tested in flexure, and the
stiffness values for each beam system were recorded. Analysis of the load deflection data showed that beam specimens reinforced with CFRP exhibit three different
stiffness characteristics: uncracked,
stiffness behavior at the cracking point, and post-cracking
stiffness. When exposed to moisture it was discovered that water immersion produced lower uncracked
stiffness values than the
control specimens. However, there appeared to be little correlation between
stiffness performance and immersion temperature. Specimens exposed to tidal conditions show decreased flexural
stiffness compared to the
control specimens. Behavior at the cracking point was found to be highly dependant on the debonded length of the concrete and the composite strip. Specimens that experienced small debonded lengths exhibited bilinear behavior between the recorded uncracked and post-cracking
stiffness values. Composite systems immersed at elevated temperatures are more likely to exhibit bilinear behavior than the
control specimens. Meanwhile, tidal exposure was found to reduce the likelihood of bilinear behavior for beam specimens reinforced with CFRP. It was speculated that both of these phenomena were related to changes in the debonding length created by moisture exposure. Moisture exposure was found to have little effect on the post-cracking
stiffness values. In some instances it was recorded that moisture exposure could produce post-cracking
stiffness values higher than the
control specimens. It was speculated that the high post-cracking
stiffness values noticed for the immersed composite beam specimens was caused by unchanged or improved debonding behavior. ( en )
Advisors/Committee Members: Hamilton, Homer R. (committee chair), Cook, Ronald A. (committee member), Douglas, Elliot P. (committee member).
Subjects/Keywords: Composite materials; Concretes; Failure modes; Laminates; Specimens; Stiffness; Structural deflection; Temperature control; Water immersion; Water temperature; environment, epoxy, moisture, stiffness
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APA ·
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APA (6th Edition):
Van Etten, N. (2008). Effect of Environment on the Stiffness of Carbon Fiber Reinforced Polymer Repaired Concrete. (Masters Thesis). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0022708
Chicago Manual of Style (16th Edition):
Van Etten, Nathaniel. “Effect of Environment on the Stiffness of Carbon Fiber Reinforced Polymer Repaired Concrete.” 2008. Masters Thesis, University of Florida. Accessed January 28, 2021.
https://ufdc.ufl.edu/UFE0022708.
MLA Handbook (7th Edition):
Van Etten, Nathaniel. “Effect of Environment on the Stiffness of Carbon Fiber Reinforced Polymer Repaired Concrete.” 2008. Web. 28 Jan 2021.
Vancouver:
Van Etten N. Effect of Environment on the Stiffness of Carbon Fiber Reinforced Polymer Repaired Concrete. [Internet] [Masters thesis]. University of Florida; 2008. [cited 2021 Jan 28].
Available from: https://ufdc.ufl.edu/UFE0022708.
Council of Science Editors:
Van Etten N. Effect of Environment on the Stiffness of Carbon Fiber Reinforced Polymer Repaired Concrete. [Masters Thesis]. University of Florida; 2008. Available from: https://ufdc.ufl.edu/UFE0022708
University of Manchester
29.
Ozakturk, Meliksah.
POWER ELECTRONIC SYSTEMS DESIGN CO-ORDINATION FOR
DOUBLY-FED INDUCTION GENERATOR WIND TURBINES.
Degree: 2012, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:173342
► Wind turbine modelling using doubly-fed induction generators is a well-known subject. However, studies have tended to focus on optimising the components of the system rather…
(more)
▼ Wind turbine modelling using doubly-fed induction
generators is a well-known
subject. However, studies have tended to
focus on optimising the components of the system rather than
considering the interaction between the components. This research
examines the interaction of the
control methods for a doubly-fed
induction generator (DFIG) in a wind turbine application
integrating them with the crowbar protection
control and DC-link
brake
control to make the best use of the converter. The controls
of the rotor-side and the grid-side converters of the DFIG model
are both well established and have been shown to work. Typically
the crowbar protection is designed in order to protect the
rotor-side converter and the power electronic components of the
DFIG system from high currents occurring in the rotor due to the
faults. The DC-link brake-overvoltage protection is also designed
to prevent the overcharging of the DC-link capacitor placed between
the rotor-side converter and the grid-side converter. In order to
show that these protection schemes work and with thought can
co-ordinate with each other, tests consisting of a number of
balanced three-, two- and one-phase voltage sags are applied to the
network voltage. The main contributions of this thesis are
establishing operational tuning and design limits for the
controllers and system subassemblies. This is to minimise the
electrical subsystem interaction while maintaining adequate
performance, and have an improved DC-link
control. This work also
includes a full electrical system study of the wind turbine and an
essential literature review on significant references in the field
of the DFIG wind turbine system modelling,
control and protection.
Specifically this research project makes a number of novel
contributions to the literature: enhanced DC voltage
control
including operating point sensitivity analysis and dynamic
stiffness assessment, sensitivity and robustness analyses of the
power loop
control and
control loop segmentation by appropriately
tuning the controller loops.
Advisors/Committee Members: Barnes, Mike.
Subjects/Keywords: DFIG, control co-ordination, protection, wind turbine,
RSC, GSC; DC-link, crowbar, dynamic stiffness, robustness,
operating point analysis; PI, PID, voltage sag, tuning, PWM, loops
segmentation
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APA ·
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APA (6th Edition):
Ozakturk, M. (2012). POWER ELECTRONIC SYSTEMS DESIGN CO-ORDINATION FOR
DOUBLY-FED INDUCTION GENERATOR WIND TURBINES. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:173342
Chicago Manual of Style (16th Edition):
Ozakturk, Meliksah. “POWER ELECTRONIC SYSTEMS DESIGN CO-ORDINATION FOR
DOUBLY-FED INDUCTION GENERATOR WIND TURBINES.” 2012. Doctoral Dissertation, University of Manchester. Accessed January 28, 2021.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:173342.
MLA Handbook (7th Edition):
Ozakturk, Meliksah. “POWER ELECTRONIC SYSTEMS DESIGN CO-ORDINATION FOR
DOUBLY-FED INDUCTION GENERATOR WIND TURBINES.” 2012. Web. 28 Jan 2021.
Vancouver:
Ozakturk M. POWER ELECTRONIC SYSTEMS DESIGN CO-ORDINATION FOR
DOUBLY-FED INDUCTION GENERATOR WIND TURBINES. [Internet] [Doctoral dissertation]. University of Manchester; 2012. [cited 2021 Jan 28].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:173342.
Council of Science Editors:
Ozakturk M. POWER ELECTRONIC SYSTEMS DESIGN CO-ORDINATION FOR
DOUBLY-FED INDUCTION GENERATOR WIND TURBINES. [Doctoral Dissertation]. University of Manchester; 2012. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:173342
Penn State University
30.
Anusonti-Inthra, Phuriwat.
SEMI-ACTIVE CONTROL OF HELICOPTER VIBRATION
USING CONTROLLABLE STIFFNESS AND DAMPING DEVICES
.
Degree: 2008, Penn State University
URL: https://submit-etda.libraries.psu.edu/catalog/5986
► Semi-active concepts for helicopter vibration reduction are developed and evaluated in this dissertation. Semi-active devices, controllable stiffness devices or controllable orifice dampers, are introduced; (i)…
(more)
▼ Semi-active concepts for helicopter vibration reduction are developed and evaluated in this dissertation. Semi-active devices, controllable
stiffness devices or controllable orifice dampers, are introduced; (i) in the blade root region (rotor-based concept) and (ii) between the rotor and the fuselage as semi-active isolators (in the non-rotating frame). Corresponding semi-active controllers for helicopter vibration reduction are also developed. The effectiveness of the rotor-based semi-active vibration reduction concept (using
stiffness and damping variation) is demonstrated for a 4-bladed hingeless rotor helicopter in moderate- to high-speed forward flight. The rotor blade is modeled as an elastic beam, which undergoes elastic flap-bending, lag-bending, and torsional deformations, and is discretized using finite element analysis. Aerodynamic loads on the blade are determined using blade element theory, with rotor inflow calculated using linear inflow or free wake analysis. The
stiffness variation is introduced by modulating the
stiffness of the root element or a discrete controllable
stiffness device that connects the rotor hub and the blade. The damping variation is achieved by adjusting the damping coefficient of a controllable orifice damper, introduced in the blade root region. Optimal multi-cyclic
stiffness/damping variation inputs that can produce simultaneous reduction in all components of hub vibrations are determined through an optimal semi-active
control scheme using gradient and non-gradient based optimizations. A sensitivity study shows that the
stiffness variation of root element can reduce hub vibrations when proper amplitude and phase are used. Furthermore, the optimal semi-active
control scheme can determine the combination of
stiffness variations that produce significant vibration reduction in all components of vibratory hub loads simultaneously. It is demonstrated that desired cyclic variations in properties of the blade root region can be practically achieved using discrete controllable
stiffness devices and controllable dampers, especially in the flap and lag directions. These discrete controllable devices can produce 35-50% reduction in a composite vibration index representing all components of vibratory hub loads. No detrimental increases are observed in the lower harmonics of blade loads and blade response (which contribute to the dynamic stresses) and controllable device internal loads, when the optimal
stiffness and damping variations are introduced. The effectiveness of optimal
stiffness and damping variations in reducing hub vibration is retained over a range of cruise speeds and for variations in fundamental rotor properties. The effectiveness of the semi-active isolator is demonstrated for a simplified single degree of freedom system representing the semi-active isolation system. The rotor, represented by a lumped mass under harmonic force excitation, is supported by a spring and a parallel damper on the fuselage (assumed to have infinite mass). Properties of the spring or…
Advisors/Committee Members: Edward C Smith, Committee Member, George A Lesieutre, Committee Member, Farhan Gandhi, Committee Chair/Co-Chair, Christopher Rahn, Committee Member.
Subjects/Keywords: controllable damper; controllable stiffness; semi-active control; helicopter vibration reduction
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APA ·
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APA (6th Edition):
Anusonti-Inthra, P. (2008). SEMI-ACTIVE CONTROL OF HELICOPTER VIBRATION
USING CONTROLLABLE STIFFNESS AND DAMPING DEVICES
. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/5986
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Anusonti-Inthra, Phuriwat. “SEMI-ACTIVE CONTROL OF HELICOPTER VIBRATION
USING CONTROLLABLE STIFFNESS AND DAMPING DEVICES
.” 2008. Thesis, Penn State University. Accessed January 28, 2021.
https://submit-etda.libraries.psu.edu/catalog/5986.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Anusonti-Inthra, Phuriwat. “SEMI-ACTIVE CONTROL OF HELICOPTER VIBRATION
USING CONTROLLABLE STIFFNESS AND DAMPING DEVICES
.” 2008. Web. 28 Jan 2021.
Vancouver:
Anusonti-Inthra P. SEMI-ACTIVE CONTROL OF HELICOPTER VIBRATION
USING CONTROLLABLE STIFFNESS AND DAMPING DEVICES
. [Internet] [Thesis]. Penn State University; 2008. [cited 2021 Jan 28].
Available from: https://submit-etda.libraries.psu.edu/catalog/5986.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Anusonti-Inthra P. SEMI-ACTIVE CONTROL OF HELICOPTER VIBRATION
USING CONTROLLABLE STIFFNESS AND DAMPING DEVICES
. [Thesis]. Penn State University; 2008. Available from: https://submit-etda.libraries.psu.edu/catalog/5986
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
◁ [1] [2] [3] ▶
. 
Open Access Theses and Dissertations
