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Texas A&M University
1.
Abdelzaher, Omar Mohamed.
Downhole Wireline Mechatronics and Drillstring Vibration Dynamics.
Degree: 2014, Texas A&M University
URL: http://hdl.handle.net/1969.1/157919
► The work is divided into two parts: The First part discusses and documents simulation investigations on the interactive effect of the different conveyance accessories tools…
(more)
▼ The work is divided into two parts: The First part discusses and documents simulation investigations on the interactive effect of the different conveyance accessories tools and their designs on the wireline cable tension force, and how it can influence the wireline cable performance especially in open hole logging operations with highly deviated and rugose zones. A computer simulation model was built to predict the cable tension force applied on conveyed wireline string so as to assess and analyze the effect of the different conveyance accessories, such as centralizers, bottom-nose tools, and wireline coating, on wireline penetration rates. A numerical computing approach was then utilized to represent and analyze the simulation studies output results in a friendly graphical form. Improving the wireline logging performance, especially in highly deviated rugose openhole wells, could increase the percentage of successful logging operations, reducing time, cost and improving data quality with the increased wellbore coverage. The second part discusses the possible violent drillstring vibrations encountered during drilling and its effect on the overall rate of penetration and sustainability. This entails a complete identification and modeling of the drillstring dynamics and the sources of vibrations excitation that include stick-slip, bit-bounce, and whirling with its two forward and backward types to better control its functional operation and improve its performance.
A Matlab numerical simulator model based on Finite-Element-Method of 3D- Timoshenko beam elements is developed for this purpose to predict and simulate the rotordynamic behavior of the bottom-hole-assembly (BHA) and the PDC-Drillbit cutting dynamics. The model also includes the coupling between the torsional and bending vibrations of drillstrings with the nonlinear effects of drillstring/wellbore friction contacts. The work extends previous models of drillstring vibrations in the literature to include the destructive drillstring vibration backward whirling type with Pure rolling behavior and answers some crucial questions: the operation conditions that possibly causes backward whirl vibrations, possible stabilizers? configuration to reduce chance of backward whirl, best stabilizers locations in the BHA to minimize the sever vibration effects on the drillstring, and other arising questions.
Advisors/Committee Members: Palazzolo , Alan (advisor), Ahmed, Shehab (advisor), jong%22%29&pagesize-30">
Kim,
Won-
jong (committee member).
Subjects/Keywords: Downhole; Wireline; Mechatronics; Drillstring; Vibration; Dynamics; simulation; centralizers; bottom-nose; logging; wellbore; drilling; penetration; stick-slip; bit-bounce; whirling; Matlab; Finite-Element-Method; Timoshenko; rotordynamic; bottom-hole-assembly; Drillbit; nonlinear; Pur-rolling; backward-whirl; stabilizers; BHA
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APA (6th Edition):
Abdelzaher, O. M. (2014). Downhole Wireline Mechatronics and Drillstring Vibration Dynamics. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/157919
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):
Abdelzaher, Omar Mohamed. “Downhole Wireline Mechatronics and Drillstring Vibration Dynamics.” 2014. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/157919.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Abdelzaher, Omar Mohamed. “Downhole Wireline Mechatronics and Drillstring Vibration Dynamics.” 2014. Web. 19 Feb 2019.
Vancouver:
Abdelzaher OM. Downhole Wireline Mechatronics and Drillstring Vibration Dynamics. [Internet] [Thesis]. Texas A&M University; 2014. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/157919.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Abdelzaher OM. Downhole Wireline Mechatronics and Drillstring Vibration Dynamics. [Thesis]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/157919
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
2.
Ruiz Brito, Luis A.
Control of a 3DOF Birotor Helicopter Using Robust Control Methods.
Degree: 2010, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7397
► The main topic of this thesis is to exhibit how robust control techniques can be applied to real time systems. Presently, the control techniques used…
(more)
▼ The main topic of this thesis is to exhibit how robust control techniques can be
applied to real time systems. Presently, the control techniques used in the industry are
very simple even when applied to complex systems; these techniques are intuitive and
not necessarily systematic. Moreover, the notion of optimality of robustness is absent.
Control design procedures are mostly based on SISO techniques, thus, overlooking
the intrinsic multivariable aspect of the design that a MIMO system requires.
In this thesis a modern control technique is presented to manipulate a 3DOF
birotor helicopter in real time. The objective of this research is to demonstrate the
performance of more efficient control algorithms to control these kinds of systems. The
robust method proposed in this thesis is an H infinity controller which exhibits robustness
to plant model uncertainties, and good disturbance and noise rejection.
Advisors/Committee Members: Bhattacharya, Raktim (advisor), Chakravorty, Suman (advisor), jong%22%29&pagesize-30">
Kim,
Won-
jong (committee member).
Subjects/Keywords: birotor helicopter h infinity robust control
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Ruiz Brito, L. A. (2010). Control of a 3DOF Birotor Helicopter Using Robust Control Methods. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7397
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):
Ruiz Brito, Luis A. “Control of a 3DOF Birotor Helicopter Using Robust Control Methods.” 2010. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7397.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ruiz Brito, Luis A. “Control of a 3DOF Birotor Helicopter Using Robust Control Methods.” 2010. Web. 19 Feb 2019.
Vancouver:
Ruiz Brito LA. Control of a 3DOF Birotor Helicopter Using Robust Control Methods. [Internet] [Thesis]. Texas A&M University; 2010. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7397.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ruiz Brito LA. Control of a 3DOF Birotor Helicopter Using Robust Control Methods. [Thesis]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7397
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
3.
Chen, Jinfa.
An Intelligent Human-Tracking Robot Based-on Kinect Sensor.
Degree: 2015, Texas A&M University
URL: http://hdl.handle.net/1969.1/156510
► This thesis provides an indoor human-tracking robot, which is also able to control other electrical devices for the user. The overall experimental setup consists of…
(more)
▼ This thesis provides an indoor human-tracking robot, which is also able to control other electrical devices for the user. The overall experimental setup consists of a skid-steered mobile robot, Kinect sensor, laptop, wide-angle camera and two lamps. The Kinect sensor is mounted on the mobile robot to collect position and skeleton data of the user in real time and sends it to the laptop. The laptop processes these data and then sends commands to the robot and the lamps. The wide-angle camera is mounted on the ceiling to verify the tracking performance of the Kinect sensor. A C++ program runs the camera, and a java program is used to process the data from the C++ program and the Kinect sensor and then sends the commands to the robot and the lamps. The human-tracking capability is realized by two decoupled feedback controllers for linear and rotational motions. Experimental results show that although there are small delays (0.5 s for linear motion and 1.5 s for rotational motion) and steady-state errors (0.1
m for linear motion and 1.5? for rotational motion), tests show that they are acceptable since the delays and errors do not cause the tracking distance or angle out of the desirable range (?0.05m and ? 10? of the reference input) and the tracking algorithm is robust. There are four gestures designed for the user to control the robot, two switch-mode gestures, lamp crate gesture, and lamp-selection and color change gesture. Success rates of gestures recognition are more than 90% within the detectable range of the Kinect sensor.
Advisors/Committee Members: jong%22%29&pagesize-30">
Kim,
Won-
jong (advisor),
Rathinam, Sivakumar (committee member),
Xie, Zhizhang (committee member).
Subjects/Keywords: kinect sensor; human-tracking; gesture control; feedback control; human-robot interaction
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Chen, J. (2015). An Intelligent Human-Tracking Robot Based-on Kinect Sensor. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/156510
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):
Chen, Jinfa. “An Intelligent Human-Tracking Robot Based-on Kinect Sensor.” 2015. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/156510.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Chen, Jinfa. “An Intelligent Human-Tracking Robot Based-on Kinect Sensor.” 2015. Web. 19 Feb 2019.
Vancouver:
Chen J. An Intelligent Human-Tracking Robot Based-on Kinect Sensor. [Internet] [Thesis]. Texas A&M University; 2015. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/156510.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Chen J. An Intelligent Human-Tracking Robot Based-on Kinect Sensor. [Thesis]. Texas A&M University; 2015. Available from: http://hdl.handle.net/1969.1/156510
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
4.
Tangirala, Ravindra Krishna.
Fault Analysis of Electromechanical Systems using Information Entropy Concepts.
Degree: 2011, Texas A&M University
URL: http://hdl.handle.net/1969.1/157903
► Fault analysis of mechanical and electromechanical systems has been a subject of considerable interest in the systems and control research community. Entropy, under its various…
(more)
▼ Fault analysis of mechanical and electromechanical systems has been a subject of considerable interest in the systems and control research community. Entropy, under its various formulations is an important variable, which is unrivaled when it comes to measuring order (or organization) and/or disorder (or disorganization). Researchers have successfully used entropy based concepts to solve various challenging problems in engineering, mathematics, meteorology, biotechnology, medicine, statistics etc. This research tries to analyze faults in electromechanical systems using information entropy concepts. The objectives of this research are to develop a method to evaluate signal entropy of a dynamical system using only input/output measurements, and to use this entropy measure to analyze faults within a dynamical system. Given discrete-time signals corresponding to the three-phase voltages and currents of an electromechanical system being monitored, the problem is to analyze whether or not this system is healthy.
The concepts of Shannon entropy and relative entropy come from the field of Information Theory. They measure the degree of uncertainty that exists in a system. The main idea behind this approach is that the system's dynamics may have regularities hidden in measurements that are not obvious to see. The Shannon entropy and relative entropy measures are calculated by using probability distribution functions (PDF) that are formed by sampling the time series currents and voltages of a system. The system's health is monitored by, first, sampling the currents and voltages at certain time intervals, then generating the corresponding PDFs and, finally, calculating the information entropy measures. If the system dynamics are unchanged, or in other words, the system continues to be healthy, then the relative entropy measures will be consistently low or constant. But, if the system dynamics change due to damage, then the corresponding relative entropy and Shannon entropy measures will be increasing compared to the entropy of the system with less damage.
Advisors/Committee Members: Parlos, Alexander G (advisor), Jong%22%29&pagesize-30">
Kim,
Won-
Jong (committee member),
Datta, Aniruddha (committee member).
Subjects/Keywords: Relative Entropy; Shannon Entropy; Information Entropy; Fault Analysis
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Tangirala, R. K. (2011). Fault Analysis of Electromechanical Systems using Information Entropy Concepts. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/157903
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):
Tangirala, Ravindra Krishna. “Fault Analysis of Electromechanical Systems using Information Entropy Concepts.” 2011. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/157903.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Tangirala, Ravindra Krishna. “Fault Analysis of Electromechanical Systems using Information Entropy Concepts.” 2011. Web. 19 Feb 2019.
Vancouver:
Tangirala RK. Fault Analysis of Electromechanical Systems using Information Entropy Concepts. [Internet] [Thesis]. Texas A&M University; 2011. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/157903.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Tangirala RK. Fault Analysis of Electromechanical Systems using Information Entropy Concepts. [Thesis]. Texas A&M University; 2011. Available from: http://hdl.handle.net/1969.1/157903
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
5.
Li, Gang 1984-.
Bit Resolution Improvement for Continuous Data Acquisition of Electrical Waveforms in Multiphase Energy Measurement Systems.
Degree: 2010, Texas A&M University
URL: http://hdl.handle.net/1969.1/158596
► A data acquisition platform has been previously developed that enables extraction of information about an electrical machine?s health and energy conversion efficiency by monitoring its…
(more)
▼ A data acquisition platform has been previously developed that enables extraction of information about an electrical machine?s health and energy conversion efficiency by monitoring its electrical signals. It is desired to extend the functionality of this platform to enable multi-phase signal acquisition with higher bit resolution while providing continuous waveform sampling that does not present any gaps in information acquisition.
The previously designed platform samples signals at 8 kHz and can achieve about 15 bits resolution following down sampling to 1920 Hz. To get higher bit resolution without altering the hardware, more oversampling is required. Thus, the hardware is set to sample at 64 kHz which is the maximum sampling frequency the 6-channel simultaneous sampling analog to digital converter (ADC) can provide.
Sampling at higher frequencies results in larger raw data sizes while the sampling time window remains same, and this increases the data transfer time reducing the information available for analysis in a given period of time. To address this issue, in this thesis, several proposed approaches are explored and a final hybrid solution is used. The final solution achieves about 1.3 bits improvement in signal resolution compared to the original firmware, while also performing continuous waveform acquisition if the end-to-end network delay is within expected ranges.
Advisors/Committee Members: Parlos, Alexander G (advisor), jong%22%29&pagesize-30">
Kim,
Won-
jong (committee member),
Sanchez-Sinencio, Edgar (committee member).
Subjects/Keywords: Energy measurement; Fault Detection; Continuous sampling; Bits resolution
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Li, G. 1. (2010). Bit Resolution Improvement for Continuous Data Acquisition of Electrical Waveforms in Multiphase Energy Measurement Systems. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/158596
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):
Li, Gang 1984-. “Bit Resolution Improvement for Continuous Data Acquisition of Electrical Waveforms in Multiphase Energy Measurement Systems.” 2010. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/158596.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Li, Gang 1984-. “Bit Resolution Improvement for Continuous Data Acquisition of Electrical Waveforms in Multiphase Energy Measurement Systems.” 2010. Web. 19 Feb 2019.
Vancouver:
Li G1. Bit Resolution Improvement for Continuous Data Acquisition of Electrical Waveforms in Multiphase Energy Measurement Systems. [Internet] [Thesis]. Texas A&M University; 2010. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/158596.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Li G1. Bit Resolution Improvement for Continuous Data Acquisition of Electrical Waveforms in Multiphase Energy Measurement Systems. [Thesis]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/158596
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
6.
Rogers, Adam Gregory.
Precision mechatronics lab robot development.
Degree: 2009, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2090
► This thesis presents the results from a modification of a previously existing research project titled the Intelligent Pothole Repair Vehicle (IPRV). The direction of the…
(more)
▼ This thesis presents the results from a modification of a previously existing research
project titled the Intelligent Pothole Repair Vehicle (IPRV). The direction of the
research in this thesis was changed toward the development of an industrially based
mobile robot. The principal goal of this work was the demonstration of the Precision
Mechatronics Lab (PML) robot. This robot should be capable of traversing any known
distance while maintaining a minimal position error. An optical correction capability
has been added with the addition of a webcam and the appropriate image processing
software. The primary development goal was the ability to maintain the accuracy and
performance of the robot with inexpensive and low-resolution hardware. Combining the
two abilities of dead-reckoning and optical correction on a single platform will yield a
robot with the ability to accurately travel any distance. As shown in this thesis, the
additional capability of off-loading its visual processing tasks to a remote computer
allows the PML robot to be developed with less expensive hardware. The majority of
the literature research presented in this paper is in the area of visual processing. Various
methods used in industry to accomplish robotic mobility, optical processing, image
enhancement, and target interception have been presented. This background material is
important in understanding the complexity of this field of research and the potential
application of the work conducted in this thesis. The methods shown in this research can
be extended to other small robotic vehicles, with two separate drive wheels. An
empirical method based upon system identification was used to develop the motion
controllers. This research demonstrates a successful combination of a dead-reckoning capability, an optical correction method, and a simplified controller methodology
capable of accurate path following. Implementation of this procedure could be extended
to multiple and inexpensive robots used in a manufacturing setting.
Advisors/Committee Members: jong%22%29&pagesize-30">
Kim,
Won-
jong (advisor),
Choe, Yoonsuck (committee member),
Kim, Daejong (committee member).
Subjects/Keywords: robotics; mobile wheelchair
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Rogers, A. G. (2009). Precision mechatronics lab robot development. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2090
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):
Rogers, Adam Gregory. “Precision mechatronics lab robot development.” 2009. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/ETD-TAMU-2090.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Rogers, Adam Gregory. “Precision mechatronics lab robot development.” 2009. Web. 19 Feb 2019.
Vancouver:
Rogers AG. Precision mechatronics lab robot development. [Internet] [Thesis]. Texas A&M University; 2009. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2090.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Rogers AG. Precision mechatronics lab robot development. [Thesis]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2090
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
7.
Balakrishnan, Anand Kumar.
Soft switched high frequency ac-link converter.
Degree: 2009, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-3156
► Variable frequency drives typically have employed dc voltage or current links for power distribution between the input and output converters and as a means to…
(more)
▼ Variable frequency drives typically have employed dc voltage or current links
for power distribution between the input and output converters and as a means to
temporarily store energy. The dc link based power conversion systems have several
inherent limitations. One of the important limitations is the high switching loss
and high device stress which occur during switching intervals. This severely reduces
the practical switching frequencies. Additionally, while the cost, size, and weight of
the basic voltage sourced PWM drive is attractive, difficulties with input harmonics,
output dV/dt and over-voltage, EMI/RFI, tripping with voltage sags, and other
problems significantly diminish the economic competiveness of these drives. Add-ons
are available to mitigate these problems, but may result in doubling or tripling the
total costs and losses, with accompanying large increases in volume and weight.
This research investigates the design, control, operation and efficiency calculation
of a new power converter topology for medium and high power ac-ac, ac-dc and
dc-ac applications. An ac-link formed by an inductor-capacitor pair replaces the
conventional dc-link. Each leg of the converter is formed by two bidirectional switches.
Power transfer from input to output is accomplished via a link inductor which is first
charged from the input phases, then discharged to the output phases with a precisely
controllable current PWM technique. Capacitance in parallel with the link inductor
produces low turn-off losses. Turn-on is always at zero voltage as each switch swings
from reverse to forward bias. Reverse recovery is with low dI/dt and also is buffered
due to the link capacitance.
Advisors/Committee Members: Toliyat, Hamid (advisor), Bhattacharyya, Shankar (committee member), Enjeti, Prasad (committee member), jong%22%29&pagesize-30">
Kim,
Won-
jong (committee member).
Subjects/Keywords: ac-ac conversion; matrix converter; soft switching; ac link
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Balakrishnan, A. K. (2009). Soft switched high frequency ac-link converter. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-3156
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):
Balakrishnan, Anand Kumar. “Soft switched high frequency ac-link converter.” 2009. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/ETD-TAMU-3156.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Balakrishnan, Anand Kumar. “Soft switched high frequency ac-link converter.” 2009. Web. 19 Feb 2019.
Vancouver:
Balakrishnan AK. Soft switched high frequency ac-link converter. [Internet] [Thesis]. Texas A&M University; 2009. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-3156.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Balakrishnan AK. Soft switched high frequency ac-link converter. [Thesis]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-3156
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
8.
Mika, Bartosz.
Design and testing of piezoelectric sensors.
Degree: 2009, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-1565
► Piezoelectric materials have been widely used in applications such as transducers, acoustic components, as well as motion and pressure sensors. Because of the material?s biocompatibility…
(more)
▼ Piezoelectric materials have been widely used in applications such as transducers, acoustic components, as well as motion and pressure sensors. Because of the material?s biocompatibility and flexibility, its applications in biomedical and biological systems have been of great scientific and engineering interest. In order to develop piezoelectric sensors that are small and functional, understanding of the material behavior is crucial. The major objective of this research is to develop a test system to evaluate the performance of a sensor made from polyvinylidene fluoride and its uses for studying insect locomotion and behaviors. A linear stage laboratory setup was designed and built to study the piezoelectric properties of a sensor during buckling deformation. The resulting signal was compared with the data obtained from sensors attached a cockroach, Blaberus discoidalis. Comparisons show that the buckling generated in laboratory settings can be used to mimic sensor deformations when attached to an insect. An analytical model was also developed to further analyze the test results. Initial analysis shows its potential usefulness in predicting the sensor charge output. Additional material surface characterization studies revealed relationships between microstructure properties and the piezoelectric response. This project shows feasibility of studying insects with the use of polyvinylidene fluoride sensors. The application of engineering materials to insect studies opens the door to innovative approaches to integrating biological, mechanical and electrical systems.
Advisors/Committee Members: Liang, Hong (advisor), Khatri, Sunil (committee member), jong%22%29&pagesize-30">
Kim,
Won-
jong (committee member).
Subjects/Keywords: Piezoelectric; PVDF; Sensor; Buckling; Insect locomotion; Cockroach
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Mika, B. (2009). Design and testing of piezoelectric sensors. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-1565
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):
Mika, Bartosz. “Design and testing of piezoelectric sensors.” 2009. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/ETD-TAMU-1565.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Mika, Bartosz. “Design and testing of piezoelectric sensors.” 2009. Web. 19 Feb 2019.
Vancouver:
Mika B. Design and testing of piezoelectric sensors. [Internet] [Thesis]. Texas A&M University; 2009. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1565.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Mika B. Design and testing of piezoelectric sensors. [Thesis]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1565
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
9.
Chao, Ying-Chin.
Unmanned Cooperative Fire-Seeking and -Fighting Robot with Bluetooth Communication and Stair-Climbing Capability.
Degree: 2010, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7780
► This thesis presents a prototype of Unmanned Cooperative Fire-Seeking and -Fighting Robots (UCSFRs) which have a new way to climb up the stairs or traverse…
(more)
▼ This thesis presents a prototype of Unmanned Cooperative Fire-Seeking and
-Fighting Robots (UCSFRs) which have a new way to climb up the stairs or traverse over
obstacles with a ball screw. There are three unmanned vehicles (one Mother Vehicle (MV)
and two Daughter Vehicles (DVs)) presented in this research. The MV can carry two DVs
to climb stairs. They can communicate with each other using Bluetooth communication
modules. The core system of the UCSFRs is a PIC 16F877 microcontroller on a 2840
development board. The software is written in C language and the interface is established
through Hyper Terminal built in Windows XP. UCSFRs are low cost unmanned vehicles
compared with other commercial ones. The double-deck structure is applied on the DVs.
The body of the MV can be extended for special purposes. In this research, there are three
tests used to verify the functionality of the UCSFRs: (1) MV?s finding and stopping fire,
(2) Communication between the MV and the DVs, and (3) the MV?s climbing stairs. In
the second test, the DVs run in the opposite direction to assist MV detect fire. By
cooperative work, they can save time finding the fire. The MV will go to the hightemperature
area according to the data sent by the DVs. Because of the features mentioned
above, UCSFRs can be used to perform dangerous tasks instead of fire-fighters.
Advisors/Committee Members: jong%22%29&pagesize-30">
Kim,
Won-
jong (advisor),
Suh, Steve (committee member),
Bhattacharyya, Shankar P. (committee member).
Subjects/Keywords: Fire-Fighting; Stair-Climbing Capability; Cooperative Robots; Unmanned Vehicle; Wireless Communication; Bluetooth
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Chao, Y. (2010). Unmanned Cooperative Fire-Seeking and -Fighting Robot with Bluetooth Communication and Stair-Climbing Capability. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7780
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):
Chao, Ying-Chin. “Unmanned Cooperative Fire-Seeking and -Fighting Robot with Bluetooth Communication and Stair-Climbing Capability.” 2010. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7780.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Chao, Ying-Chin. “Unmanned Cooperative Fire-Seeking and -Fighting Robot with Bluetooth Communication and Stair-Climbing Capability.” 2010. Web. 19 Feb 2019.
Vancouver:
Chao Y. Unmanned Cooperative Fire-Seeking and -Fighting Robot with Bluetooth Communication and Stair-Climbing Capability. [Internet] [Thesis]. Texas A&M University; 2010. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7780.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Chao Y. Unmanned Cooperative Fire-Seeking and -Fighting Robot with Bluetooth Communication and Stair-Climbing Capability. [Thesis]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7780
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
10.
Zhang, Junjie.
Practical Issues in Formation Control of Multi-Robot Systems.
Degree: 2010, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7886
► Considered in this research is a framework for effective formation control of multirobot systems in dynamic environments. The basic formation control involves two important considerations:…
(more)
▼ Considered in this research is a framework for effective formation control of multirobot
systems in dynamic environments. The basic formation control involves two important
considerations: (1) Real-time trajectory generation algorithms for distributed control
based on nominal agent models, and (2) robust tracking of reference trajectories under
model uncertainties.
Proposed is a two-layer hierarchical architecture for collectivemotion control ofmultirobot
nonholonomic systems. It endows robotic systems with the ability to simultaneously
deal with multiple tasks and achieve typical complex formation missions, such as collisionfree
maneuvers in dynamic environments, tracking certain desired trajectories, forming
suitable patterns or geometrical shapes, and/or varying the pattern when necessary.
The study also addresses real-time formation tracking of reference trajectories under
the presence of model uncertainties and proposes robust control laws such that over each
time interval any tracking errors due to system uncertainties are driven down to zero prior to
the commencement of the subsequent computation segment. By considering a class of nonlinear
systems with favorable finite-time convergence characteristics, sufficient conditions
for exponential finite-time stability are established and then applied to distributed formation
tracking controls. This manifests in the settling time of the controlled system being finite
and no longer than the predefined reference trajectory segment computing time interval,
thus making tracking errors go to zero by the end of the time horizon over which a segment
of the reference trajectory is generated. This way the next segment of the reference trajectory is properly initialized to go into the trajectory computation algorithm. Consequently
this could lead to a guarantee of desired multi-robot motion evolution in spite of system
uncertainties.
To facilitate practical implementation, communication among multi-agent systems is
considered to enable the construction of distributed formation control. Instead of requiring
global communication among all robots, a distributed communication algorithm is employed
to eliminate redundant data propagation, thus reducing energy consumption and
improving network efficiency while maintaining connectivity to ensure the convergence of
formation control.
Advisors/Committee Members: Jayasuriya, Suhada (advisor), Palazzolo, Alan (committee member), jong%22%29&pagesize-30">
Kim,
Won-
jong (committee member),
Song, Dezhen (committee member).
Subjects/Keywords: Formation Control; Multi-Robot Systems; Uncertainty; Finite-Time Stability; Robust Control; Time-Delay
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zhang, J. (2010). Practical Issues in Formation Control of Multi-Robot Systems. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7886
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):
Zhang, Junjie. “Practical Issues in Formation Control of Multi-Robot Systems.” 2010. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7886.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Zhang, Junjie. “Practical Issues in Formation Control of Multi-Robot Systems.” 2010. Web. 19 Feb 2019.
Vancouver:
Zhang J. Practical Issues in Formation Control of Multi-Robot Systems. [Internet] [Thesis]. Texas A&M University; 2010. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7886.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Zhang J. Practical Issues in Formation Control of Multi-Robot Systems. [Thesis]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7886
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
11.
Bibinagar, Naveen Kumar.
Robustness of Ethernet-Based Real-Time Networked Control System with Multi-Level Client/Server Architecture.
Degree: 2010, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8368
► The importance of real-time communication at the device level in a factory automation setup is a widely researched area. This research is an effort to…
(more)
▼ The importance of real-time communication at the device level in a factory
automation setup is a widely researched area. This research is an effort to experimentally
verify if Ethernet can be used as a real-time communication standard in a factory
automation setup, by observing the effects of packet delays, packet loss, and network
congestion on the performance of a networked control system (NCS). The NCS
experimental setup used in this research involves real-time feedback control of multiple
plants like DC motors and a magnetic-levitation system connected to one or more
controllers. A multi-client-multi-server architecture on a local area network (LAN) was
developed using user datagram protocol (UDP) as the communication protocol. Key
observations are as follows. (1) The multi-client-single-server system showed the highest
packet delays compared to single-client-single-server architecture. (2) In the singleclient-
single-server system, as the Ethernet link utilization increased beyond 82 percent, the
average packet delays and steady-state error of the DC motor speed-control system
increased by 2231 percent and 304 percent, respectively. (3) Even under high link utilization, adding
an additional server to the NCS reduced average packet delays considerably. (4) With
large packet sizes, higher packet rates were automatically throttled by Ethernet?s flow
control mechanism affecting the real-time communication negatively. (5) In the multiclient-
multi-server architecture, average packet delays at higher packet rates, and at
higher packet lengths were found to be 40 percent lesser than the those of the single-clientsingle-
server system and 87.5 percent lesser than those of the multi-client-single-server
system.
Advisors/Committee Members: jong%22%29&pagesize-30">
Kim,
Won-
jong (advisor),
Rasmussen, Bryan (committee member),
Toliyat, Hamid (committee member).
Subjects/Keywords: NCS, Real-Time; Ethernet; Networked Control System; Switched Ethernet
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Bibinagar, N. K. (2010). Robustness of Ethernet-Based Real-Time Networked Control System with Multi-Level Client/Server Architecture. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8368
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):
Bibinagar, Naveen Kumar. “Robustness of Ethernet-Based Real-Time Networked Control System with Multi-Level Client/Server Architecture.” 2010. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8368.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Bibinagar, Naveen Kumar. “Robustness of Ethernet-Based Real-Time Networked Control System with Multi-Level Client/Server Architecture.” 2010. Web. 19 Feb 2019.
Vancouver:
Bibinagar NK. Robustness of Ethernet-Based Real-Time Networked Control System with Multi-Level Client/Server Architecture. [Internet] [Thesis]. Texas A&M University; 2010. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8368.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Bibinagar NK. Robustness of Ethernet-Based Real-Time Networked Control System with Multi-Level Client/Server Architecture. [Thesis]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8368
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
12.
Chen, Chien-Fan.
Closed-loop Real-time Control of a Novel Linear Magnetostrictive Actuator.
Degree: 2010, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8470
► This thesis presents the design of various closed-loop real-time control of a novel linear magnetostrictive actuator. The novel linear magnetostrictive actuator which uses Terfenol-D as…
(more)
▼ This thesis presents the design of various closed-loop real-time control of a novel
linear magnetostrictive actuator. The novel linear magnetostrictive actuator which uses
Terfenol-D as the magnetostrictive material was developed by Sadighi. It solves the
problem of power consumption in a conventional magnetostrictive actuator. However,
the control system of this magnetostrictive actuator cannot control the current in the coils,
which limits the performances of the real-time position control. In the closed-loop
real-time control system proposed in this thesis, the controller is designed depending on
the change of current.
The closed-loop real-time control design focused on the position control of the
active element in the novel linear magnetostrictive actuator. The closed-loop
position-control system of the linear magnetostrictive actuator was successfully designed
by implementing a closed-loop current-control system as an inner loop of the entire
control system. This design offers the flexibility to design various position controllers in
the closed-loop position-control system.
The closed-loop current-control design uses pulse-width modulation (PWM)
signal to change the current in the coils of the novel linear magnetostrictive actuator. By
changing the duty ratio of the PWM signal, the current in the coils can be changed from
zero to its maximum value. With a current controller using an integrator with a gain of
10, the current can be controlled with high response time and an error of /- 0.01 A.
The position-controller design was successfully conducted by using four different
approaches. First, a proportional-integral-derivative (PID) controller which was designed
by relay-auto tuning method with experiments exhibited a position error of ?1 ?
m with a
5 ?
m peak-to-peak position noise. Second, a PID controller which was designed by
root-locus can control the position with a position error of /- 3-4 ?
m with a 5 ?
m
peak-to-peak position noise. Third, a linear variable velocity controller exhibited a
position error of /-5 ?
m with a 5 mu
m peak-to-peak position noise. Then, the sliding mode
control (SMC) exhibited a position error of /-5 ?
m with a 5 ?
m peak-to-peak position
noise.
Advisors/Committee Members: jong%22%29&pagesize-30">
Kim,
Won-
jong (advisor),
Bhattacharyya, Shankar P. (committee member),
Rasmussen, Bryan (committee member).
Subjects/Keywords: Magnetostrictive Actuator; closed-loop current-control; closed-loop position-control
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Chen, C. (2010). Closed-loop Real-time Control of a Novel Linear Magnetostrictive Actuator. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8470
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):
Chen, Chien-Fan. “Closed-loop Real-time Control of a Novel Linear Magnetostrictive Actuator.” 2010. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8470.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Chen, Chien-Fan. “Closed-loop Real-time Control of a Novel Linear Magnetostrictive Actuator.” 2010. Web. 19 Feb 2019.
Vancouver:
Chen C. Closed-loop Real-time Control of a Novel Linear Magnetostrictive Actuator. [Internet] [Thesis]. Texas A&M University; 2010. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8470.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Chen C. Closed-loop Real-time Control of a Novel Linear Magnetostrictive Actuator. [Thesis]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8470
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
13.
Han, Xu.
Analysis and Simulation of Mechanical Trains Driven by Variable Frequency Drive Systems.
Degree: 2012, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8666
► Induction motors and Variable Frequency Drives (VFDs) are widely used in industry to drive machinery trains. However, some mechanical trains driven by VFD-motor systems have…
(more)
▼ Induction motors and Variable Frequency Drives (VFDs) are widely used in industry to drive machinery trains. However, some mechanical trains driven by VFD-motor systems have encountered torsional vibration problems. This vibration can induce large stresses on shafts and couplings, and reduce the lifetime of these mechanical parts. Long before the designed lifetime, the mechanical train may encounter failure. This thesis focuses on VFDs with voltage source rectifiers for squirrel-cage induction motors of open-loop Volts/Hertz and closed-loop Field Oriented Control (FOC). First, the torsional vibration problems induced by VFDs are introduced. Then, the mathematical model for a squirrel-cage induction motor is given. Two common control methods used in VFD are discussed - open-loop Volts/Hertz and closed-loop FOC. SimPowerSystems and SimMechanics are used as the modeling software for electrical systems and mechanical systems respectively. Based on the models and software, two interface methods are provided for modeling the coupled system. A simple system is tested to verify the interface methods. The study of open-loop Volts/Hertz control method is performed. The closed-form of electromagnetic torque sideband frequency due to Pulse Width Modulation is given. A torsional resonance case is illustrated. The effects of non-ideal power switches are studied, which shows little in uence on the system response but which uses little energy consumption. A study of a non-ideal DC bus indicates that a DC bus voltage ripple can also induce a big torsional vibration. Next, the study of the closed-loop FOC control method is presented. Simulation for a complete VFD machinery train is performed. With the recti er and DC bus dynamic braking, the system shows a better performance than the ideal-DC bus case. Lastly, a parametric study of the FOC controller is performed. The effects of primary parameters are discussed. The results indicate that some control parameters (i.e. speed ramps, proportional gain in speed PI controller) are also responsible for the mechanical torsional vibration.
Advisors/Committee Members: Palazzolo, Alan B. (advisor), jong%22%29&pagesize-30">
Kim,
Won-
jong (committee member),
Toliyat, Hamid A. (committee member).
Subjects/Keywords: Vibration; Variable Frequency Drive; VFD; Field Oriented Control; Mechanical System; Resonance; SimPowerSystems; SimMechanics
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Han, X. (2012). Analysis and Simulation of Mechanical Trains Driven by Variable Frequency Drive Systems. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8666
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):
Han, Xu. “Analysis and Simulation of Mechanical Trains Driven by Variable Frequency Drive Systems.” 2012. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8666.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Han, Xu. “Analysis and Simulation of Mechanical Trains Driven by Variable Frequency Drive Systems.” 2012. Web. 19 Feb 2019.
Vancouver:
Han X. Analysis and Simulation of Mechanical Trains Driven by Variable Frequency Drive Systems. [Internet] [Thesis]. Texas A&M University; 2012. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8666.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Han X. Analysis and Simulation of Mechanical Trains Driven by Variable Frequency Drive Systems. [Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8666
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
14.
Lopez, Thomas Jai.
Subsurface Flow Management and Real-Time Production Optimization using Model Predictive Control.
Degree: 2012, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10561
► One of the key challenges in the Oil & Gas industry is to best manage reservoirs under different conditions, constrained by production rates based on…
(more)
▼ One of the key challenges in the Oil & Gas industry is to best manage reservoirs under different conditions, constrained by production rates based on various economic scenarios, in order to meet energy demands and maximize profit. To address the energy demand challenges, a transformation in the paradigm of the utilization of "real-time" data has to be brought to bear, as one changes from a static decision making to a dynamical and data-driven management of production in conjunction with real-time risk assessment. The use of modern methods of computational modeling and simulation may be the only means to account for the two major tasks involved in this paradigm shift: (1) large-scale computations; and (2) efficient utilization of the deluge of data streams.
Recently, history matching and optimization were brought together in the oil industry into an integrated and more structured approach called optimal closed-loop reservoir management. Closed-loop control algorithms have already been applied extensively in other engineering fields, including aerospace, mechanical, electrical and chemical engineering. However, their applications to porous media flow, such as - in the current practices and improvements in oil and gas recovery, in aquifer management, in bio-landfill optimization, and in CO2 sequestration have been minimal due to the large-scale nature of existing problems that generate complex models for controller design and real-time implementation. Their applicability to a realistic field is also an open topic because of the large-scale nature of existing problems that generate complex models for controller design and real-time implementation, hindering its applicability.
Basically, three sources of high-dimensionality can be identified from the underlying reservoir models: size of parameter space, size of state space, and the number of scenarios or realizations necessary to account for uncertainty. In this paper we will address type problem of high dimensionality by focusing on the mitigation of the size of the state-space models by means of model-order reduction techniques in a systems framework. We will show how one can obtain accurate reduced order models which are amenable to fast implementations in the closed-loop framework .The research will focus on System Identification (System-ID) (Jansen, 2009) and Model Predictive Control (MPC) (Gildin, 2008) to serve this purpose.
A mathematical treatment of System-ID and MPC as applied to reservoir simulation will be presented. Linear MPC would be studied on two specific reservoir models after generating low-order reservoir models using System-ID methods. All the comparisons are provided from a set of realistic simulations using the commercial reservoir simulator called Eclipse. With the improvements in oil recovery and reductions in water production effectively for both the cases that were considered, we could reinforce our stance in proposing the implementation of MPC and System-ID towards the ultimate goal of "real-time" production optimization.
Advisors/Committee Members: Gildin, Eduardo (advisor), Gupta, Akhil D. (committee member), jong%22%29&pagesize-30">
Kim,
Won-
jong (committee member).
Subjects/Keywords: Reservoir Simulation; Control; Smart Wells; Model Predictive Control; System Identification; Subspace Identification; MPC
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lopez, T. J. (2012). Subsurface Flow Management and Real-Time Production Optimization using Model Predictive Control. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10561
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):
Lopez, Thomas Jai. “Subsurface Flow Management and Real-Time Production Optimization using Model Predictive Control.” 2012. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10561.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Lopez, Thomas Jai. “Subsurface Flow Management and Real-Time Production Optimization using Model Predictive Control.” 2012. Web. 19 Feb 2019.
Vancouver:
Lopez TJ. Subsurface Flow Management and Real-Time Production Optimization using Model Predictive Control. [Internet] [Thesis]. Texas A&M University; 2012. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10561.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Lopez TJ. Subsurface Flow Management and Real-Time Production Optimization using Model Predictive Control. [Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10561
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
15.
Saeed, Ahmed.
Vibration Suppression and Flywheel Energy Storage in a Drillstring Bottom-Hole-Assembly.
Degree: 2012, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11035
► In this study, a novel concept for a downhole flywheel energy storage module to be embedded in a bottom-hole-assembly (BHA) is presented and modeled, as…
(more)
▼ In this study, a novel concept for a downhole flywheel energy storage module to be embedded in a bottom-hole-assembly (BHA) is presented and modeled, as an alternative power source to existing lithium-ion battery packs currently deployed in measurement-while-drilling (MWD) or logging-while-drilling (LWD) operations. Lithium-ion batteries disadvantages include deteriorated performance in high temperature, limited lifetime that necessitates frequent replacement which elevates operational costs, and environmental disposal. Extreme and harsh downhole conditions necessitate that the flywheel module withstands temperatures and pressures exceeding 300 ?F and 20 kpsi, respectively, as well as violent vibrations encountered during drilling. Moreover, the flywheel module should adhere to the geometric constraints of the wellbore and its corresponding BHA.
Hence, a flywheel sizing procedure was developed that takes into consideration the required energy to be stored, the surrounding environmental conditions, and the geometric constraints. A five-axis magnetic levitation control system was implemented and tuned to maintain continuous suspension of the flywheel under the harsh lateral, axial and torsional drilling vibrations of the BHA. Thus, an integrated finite element model was developed that included the rotordynamic behavior of the flywheel and the BHA, the component dynamics of the magnetic levitation control system, and the cutting dynamics of the drillbit for both PDC and tricone types. The model also included a newly developed coupling between lateral, axial and torsional vibrations. It was demonstrated through simulations conducted by numerical integration that the flywheel maintains levitation due to all different types of external vibration as well as its own lateral vibration due to mass unbalance. Moreover, a passive proof-mass-damper (PPMD) was developed that suppresses axial bit-bounce vibrations as well as torsional vibrations, and was extended to also mitigate lateral vibrations. Optimized values of the mass, stiffness and damping values of the PPMD were obtained by the hybrid analytical-numerical Chebyshev spectral method that was superior in computational efficiency to iterative numerical integration. This also enabled the fine-plotting of an operating stability chart indicating stability regions where bit-bounce and stick-slip are avoided. The proof-mass-damping concept was extended to the flywheel to be an active proof-mass-damper (APMD) where simulations indicated functionality for a light-weight BHA.
Advisors/Committee Members: Palazzolo, Alan B. (advisor), Ahmed, Shehab (advisor), jong%22%29&pagesize-30">
Kim,
Won-
jong (committee member),
McAdams, Daniel (committee member).
Subjects/Keywords: Downhole Flywheel; Bottom-Hole-Assembly (BHA); Drillstring Vibrations; Drillbit Cutting Dynamics; Active Magnetic Bearing (AMB)
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Saeed, A. (2012). Vibration Suppression and Flywheel Energy Storage in a Drillstring Bottom-Hole-Assembly. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11035
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):
Saeed, Ahmed. “Vibration Suppression and Flywheel Energy Storage in a Drillstring Bottom-Hole-Assembly.” 2012. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11035.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Saeed, Ahmed. “Vibration Suppression and Flywheel Energy Storage in a Drillstring Bottom-Hole-Assembly.” 2012. Web. 19 Feb 2019.
Vancouver:
Saeed A. Vibration Suppression and Flywheel Energy Storage in a Drillstring Bottom-Hole-Assembly. [Internet] [Thesis]. Texas A&M University; 2012. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11035.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Saeed A. Vibration Suppression and Flywheel Energy Storage in a Drillstring Bottom-Hole-Assembly. [Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11035
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
16.
Allen, Justin Aaron.
Design of active suspension control based upon use of tubular linear motor and quarter-car model.
Degree: 2008, Texas A&M University
URL: http://hdl.handle.net/1969.1/86036
► The design, fabrication, and testing of a quarter-car facility coupled with various control algorithms are presented in this thesis. An experimental linear tubular motor, capable…
(more)
▼ The design, fabrication, and testing of a quarter-car facility coupled with various
control algorithms are presented in this thesis. An experimental linear tubular motor,
capable of producing a 52-N force, provides control actuation to the model. Controllers
consisting of two designs were implemented: a classical controller employing lead and
lag networks and a state-space feedback design. Each design was extensively simulated
to screen for receptiveness to actuation force limitations and robustness regarding the
inexact tire modeling. The goal of each controller was to minimize the acceleration of
the sprung mass in the presence of simulated road disturbances, modeled by both
sinusoidal and step input excitation wheels.
Different reference velocity inputs were applied to the control scheme. Responses
to a zero reference were juxtaposed to those that resulted from tracking a reference built
off a model that incorporated inertial-frame damping attached to the sprung mass. The
outcome of this comparison was that low-frequency disturbances were attenuated better
when tracking a zero reference, but the reference relaxation introduced by the inertialframe
damping model allowed for better-attenuated high frequency signals. Employing
an inertial-frame damping value of 250 N-s/
m, the rejected frequency component of the
system response synchronous with the disturbance input excitation of 40 rad/s bettered by
33% and 28% when feeding control force from the classical controller and state-space
controller, respectively.
The experimental analysis conducted on the classical and state-space controllers
produced sinusoidal disturbance rejection of at worst 50% within their respective
bandwidths. At 25 rad/s, the classical controller was able to remove 80% of the base component synchronous with the disturbance excitation frequency, while the state-space
controller filtered out nearly 60%.
Analysis on the system's ability to reject step disturbances was greatly
confounded with the destructive lateral loading transferred during the excitation process.
As a result, subjection to excitation could only occur up to 25 rad/s. At the 20 rad/s
response synchronous to the disturbance excitation, the classical and state-space
controllers removed 85% and 70% of the disturbance, respectively. Sharp spikes in timebased
amplitude were present due to the binding that ensued during testing.
Advisors/Committee Members: jong%22%29&pagesize-30">
Kim,
Won-
jong (advisor),
Swaroop, Darbha (committee member),
Bhattacharyya, Shankar (committee member).
Subjects/Keywords: control; active suspension
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Allen, J. A. (2008). Design of active suspension control based upon use of tubular linear motor and quarter-car model. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/86036
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):
Allen, Justin Aaron. “Design of active suspension control based upon use of tubular linear motor and quarter-car model.” 2008. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/86036.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Allen, Justin Aaron. “Design of active suspension control based upon use of tubular linear motor and quarter-car model.” 2008. Web. 19 Feb 2019.
Vancouver:
Allen JA. Design of active suspension control based upon use of tubular linear motor and quarter-car model. [Internet] [Thesis]. Texas A&M University; 2008. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/86036.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Allen JA. Design of active suspension control based upon use of tubular linear motor and quarter-car model. [Thesis]. Texas A&M University; 2008. Available from: http://hdl.handle.net/1969.1/86036
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
17.
Ozkeskin, Fatih Mert.
Feedback Controlled High Frequency Electrochemical Micromachining.
Degree: 2008, Texas A&M University
URL: http://hdl.handle.net/1969.1/86041
► Microsystem and integrated circuitry components are mostly manufactured using semiconductor technologies. Fabrication using high strength metals, for demanding aerospace, mechanical, or biomedical applications, requires novel…
(more)
▼ Microsystem and integrated circuitry components are mostly manufactured using
semiconductor technologies. Fabrication using high strength metals, for demanding
aerospace, mechanical, or biomedical applications, requires novel technologies which
are different from those for silicon. A promising mass production method for
micro/meso scale components is electrochemical micromachining.
The complex system, however, requires high precision mechanical fixtures and
sophisticated instrumentation for proper process control. This study presents an
electrochemical micromachining system with a closed-loop feedback control
programmed using a conditional binary logic approach.
The closed-loop control is realized using electrical current as the dynamic
feedback signal. The control system improves material removal rate by 250% through
optimizing inter electrode gap and provides robust automation reducing machining
variation by 88%. The new system evokes production of higher quality
microcomponents. Workpiece damage is reduced by 97% and increased feature
sharpness is observed.
Advisors/Committee Members: Hung, Wayne Nguyen P. (advisor), Cheng, Xing (committee member), jong%22%29&pagesize-30">
Kim,
Won-
jong (committee member).
Subjects/Keywords: microECM; micromachining; inter electrode gap; feedback control
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ozkeskin, F. M. (2008). Feedback Controlled High Frequency Electrochemical Micromachining. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/86041
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):
Ozkeskin, Fatih Mert. “Feedback Controlled High Frequency Electrochemical Micromachining.” 2008. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/86041.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ozkeskin, Fatih Mert. “Feedback Controlled High Frequency Electrochemical Micromachining.” 2008. Web. 19 Feb 2019.
Vancouver:
Ozkeskin FM. Feedback Controlled High Frequency Electrochemical Micromachining. [Internet] [Thesis]. Texas A&M University; 2008. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/86041.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ozkeskin FM. Feedback Controlled High Frequency Electrochemical Micromachining. [Thesis]. Texas A&M University; 2008. Available from: http://hdl.handle.net/1969.1/86041
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
18.
Banneyake, Bm U.
Development of a Microfluidic Device for Synthesis of Lipid Bi-Layer In-Situ.
Degree: 2010, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2008-12-79
► Lipid bi-layers are ubiquitous components of biological cells and are found in a variety of cell components. In biological membranes, lipid bi-layer membranes carry membrane…
(more)
▼ Lipid bi-layers are ubiquitous components of biological cells and are found in a variety of cell components. In biological membranes, lipid bi-layer membranes carry membrane proteins, which control transport of material and communication of signals in and out the cell. There are several disadvantages involved with patch clamping method as a way of studying biological membranes and protein interactions. Hence, artificial synthesis of bi-layer has been of great interest in basic biophysical studies, drug discoveries in pharmaceutical studies and study of protein nanopores for precise engineering applications. However, conventional lipid bi-layer synthesis techniques require skilled operators, have low repeatability (reliability), have portability restrictions and result in unstable bi-layers having a short lifetime.
In this investigation a novel microfluidic device and a method for artificial synthesis of lipid bi-layer in-situ are explored. In the proposed method, lipid trapped at an aperture on a Teflon sheet, is thinned to form a lipid bi-layer by a continuous flow of buffer solution on both sides of the aperture in the microfluidic device. The microfluidic device is expected to have advantages from its compact design. Further, the new approach is expected to be repetitive and good for automation removing the requirement of a skilled operator.
The microfluidic device was fabricated using two glass substrates. Two channels of ? ? shape were etched and through holes were fabricated at all four terminal ends of the microchannels on each glass substrate. A thin Teflon sheet carrying a 100?
m diameter hole was sandwiched between the two glass wafers forming two sets of microchannels on both sides of the aperture. An analytical microfluid model of the microchannels was developed to investigate the nature of the flow and to select microchannel parameters. Experiments using the proposed device were performed to verify the feasibility of the novel approach for lipid bi-layer synthesis. Experimental results suggest formation of a lipid bi-layer at an aperture on the Teflon sheet but further investigation might be necessary for verification. Life time of the bi-layer is short mainly due to low quality of the used aperture.
Advisors/Committee Members: Banerjee, Debjyoti (advisor), Jong%22%29&pagesize-30">
Kim,
Won-
Jong (committee member),
Ugaz, Victor M. (committee member).
Subjects/Keywords: Keyword 1; Lipid Bi-Layer Synthesis; Keyword 2; Microfluidic
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Banneyake, B. U. (2010). Development of a Microfluidic Device for Synthesis of Lipid Bi-Layer In-Situ. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2008-12-79
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):
Banneyake, Bm U. “Development of a Microfluidic Device for Synthesis of Lipid Bi-Layer In-Situ.” 2010. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/ETD-TAMU-2008-12-79.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Banneyake, Bm U. “Development of a Microfluidic Device for Synthesis of Lipid Bi-Layer In-Situ.” 2010. Web. 19 Feb 2019.
Vancouver:
Banneyake BU. Development of a Microfluidic Device for Synthesis of Lipid Bi-Layer In-Situ. [Internet] [Thesis]. Texas A&M University; 2010. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2008-12-79.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Banneyake BU. Development of a Microfluidic Device for Synthesis of Lipid Bi-Layer In-Situ. [Thesis]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2008-12-79
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
19.
Lee, Minhyung.
Real-Time Networked Control with Multiple Clients.
Degree: 2010, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-891
► In this thesis closed-loop control strategies over a communication network with multiple clients are developed. To accomplish this objective, a steel-ball magnetic-levitation system, a DC…
(more)
▼ In this thesis closed-loop control strategies over a communication network with multiple clients are developed. To accomplish this objective, a steel-ball magnetic-levitation system, a DC motor speed-control system, and an autonomous wheelchair robot referred to as Clients 1, 2, and 3, respectively were used as Networked-Based-control (NCS) test beds to validate the proposed strategies. For real-time operation, Linux with Real-Time Application Interface (RTAI) and Control and Measurement Interface (Comedi) were used as the operating system for Clients 1 and 2. Client 3's software was written in Microsoft Visual Basic 6.0 on the Windows XP operating system (OS). User datagram protocol (UDP) was used as the communication network protocol in this research due to its better real-time performance instead of transmission control protocol (TCP). Although UDP has no guarantee for transferring data, it has smaller overheads and less time delay than TCP.
Since the robotic wheelchair and the server are run on different OSs, Samba was used to put both systems into the same LAN with a fast data-transmission speed. Using Samba, the round-trip communication time between the robotic wheelchair and the server is only 11.2 ms whereas 30.8 ms is taken without using Samba.
When the server receives the sensor data from multiple clients at the same time, the NCS stability may be deteriorated due to the limitation of the system bandwidth. The NCS stability is affected by the sampling period of the system, and the reduction of the sampling period improves the control loop's performance. However, a shorter sampling period requires more network bandwidth to transmit more sensor data or control data, which increases the network traffic load.
Using the PING test, the transmission time for each control loop was measured. The processing time for each system was also measured by a time-stamp function, and the operation time for each control loop was obtained. In order to maintain the NCS stable, several combinations of the sampling periods for each client are suggested and verified. The bandwidth utilization of Client 1 is set to be 43.5% and the range of the bandwidth utilization of Client 2 with guaranteed stability was found to be between 9.1% and 45.3%. Thus, the bandwidth utilization of Client 3 is from 11.8% to 46.8%. The multiple-client NCS test bed could maintain its stability within these ranges of the bandwidth utilizations of all clients.
Advisors/Committee Members: jong%22%29&pagesize-30">
Kim,
Won-
jong (advisor),
Langari, Reza (committee member),
Datta, Aniruddha (committee member).
Subjects/Keywords: NCS; multiple clients; system stability
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lee, M. (2010). Real-Time Networked Control with Multiple Clients. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-891
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):
Lee, Minhyung. “Real-Time Networked Control with Multiple Clients.” 2010. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-891.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Lee, Minhyung. “Real-Time Networked Control with Multiple Clients.” 2010. Web. 19 Feb 2019.
Vancouver:
Lee M. Real-Time Networked Control with Multiple Clients. [Internet] [Thesis]. Texas A&M University; 2010. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-891.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Lee M. Real-Time Networked Control with Multiple Clients. [Thesis]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-891
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
20.
Chiu, Cheng-Wei 1979-.
Interfacial Interactions between Implant Electrode and Biological Environment.
Degree: 2012, Texas A&M University
URL: http://hdl.handle.net/1969.1/148123
► Electrodes implanted into neural systems are known to degrade due to encapsulation by surrounding tissues. The mechanisms of electrode-tissue interactions and prediction of the behavior…
(more)
▼ Electrodes implanted into neural systems are known to degrade due to encapsulation by surrounding tissues. The mechanisms of electrode-tissue interactions and prediction of the behavior of electrode are yet to be achieved.
This research will aim at establishing the fundamental knowledge of interfacial interactions between the host biological environment and an implanted electrode. We will identify the dynamic mechanisms of such interfacial interactions. Quantitative analysis of the electrical properties of interface will be conducted using Electrochemical Impedance Spectroscopy (EIS). Results will be used to develop a general model to interpret electrical circuitry of the interface. This is expected to expand our understanding in the effects of interfacial interactions to the charge transport.
The interfacial interactions of an implanted electrode with neural system will be studied in two types of electrodes: silver and graphene coated. The interfacial impedance of both samples will be studied using EIS. The development of the cellular interaction will be investigated using histological procedure. X-ray photoemission spectroscopy (XPS) will be employed to study the chemical effects on the silver electrodes. Atomic force microscopy and Raman spectroscopy will be used for material characterization of graphene-coated electrodes.
In the study of silver electrode, two mechanisms affecting the interfacial impedance are proposed. First is the formation of silver oxide. The other is the immuno-response of tissue encapsulation. Histological results suggest that higher cell density cause higher impedance magnitude at the interface. It is also found that the cellular encapsulation dominates the increase in impedance for longer implanted time.
In the study of graphene-coated electrode, it is found that the graphene can strongly prevent the metal substrate from being oxidized. It not only provides good electrical conductivity for signal transport, but also reduces the speed of the accumulation of tissue around the electrode. Such characteristics of graphene have great potential in the application of neural implant.
Finally, the dynamic mechanisms of biological interaction are proposed. A model is also developed to represent the general circuitry of the interface between an implanted electrode and the neural system. The model has three major components, which are interfacial double layer, cellular encapsulation, and the substrate. The model presented in this study can compensate for selection and prediction of materials and their behaviors.
Advisors/Committee Members: Liang, Hong (advisor), Harlow, Mark (committee member), Ames, Aaron (committee member), jong%22%29&pagesize-30">
Kim,
Won-
jong (committee member).
Subjects/Keywords: Interfacial interaction; Neural Implant
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Chiu, C. 1. (2012). Interfacial Interactions between Implant Electrode and Biological Environment. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/148123
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):
Chiu, Cheng-Wei 1979-. “Interfacial Interactions between Implant Electrode and Biological Environment.” 2012. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/148123.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Chiu, Cheng-Wei 1979-. “Interfacial Interactions between Implant Electrode and Biological Environment.” 2012. Web. 19 Feb 2019.
Vancouver:
Chiu C1. Interfacial Interactions between Implant Electrode and Biological Environment. [Internet] [Thesis]. Texas A&M University; 2012. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/148123.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Chiu C1. Interfacial Interactions between Implant Electrode and Biological Environment. [Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/148123
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
21.
Lai, Lin.
A Development of Design and Control Methodology for Next Generation Parallel Hybrid Electric Vehicle.
Degree: 2013, Texas A&M University
URL: http://hdl.handle.net/1969.1/149289
► Commercially available Hybrid Electric Vehicles (HEVs) have been around for more than ten years. However, their market share remains small. Focusing only on the improvement…
(more)
▼ Commercially available Hybrid Electric Vehicles (HEVs) have been around for more than ten years. However, their market share remains small. Focusing only on the improvement of fuel economy, the design tends to reduce the size of the internal combustion engine in the HEV, and uses the electrical drive to compensate for the power gap between the load demand and the engine capacity. Unfortunately, the low power density and the high cost of the combined electric motor drive and battery packs dictate that the HEV has either worse performance or much higher price than the conventional vehicle. In this research, a new design philosophy for parallel HEV is proposed, which uses a full size engine to guarantee the vehicle performance at least as good as the conventional vehicle, and hybridizes with an electrical drive in parallel to improve the fuel economy and performance beyond the conventional cars. By analyzing the HEV fuel economy versus the increasing of the electrical drive power on typical driving conditions, the optimal hybridization electric power capacity is determined. Thus, the full size engine HEV shows significant improvement in fuel economy and performance, with relatively short cost recovery period.
A new control strategy, which optimizes the fuel economy of parallel configured charge sustained hybrid electric vehicles, is proposed in the second part of this dissertation. This new approach is a constrained engine on-off strategy, which has been developed from the two extreme control strategies of maximum SOC and engine on-off, by taking their advantages and overcoming their disadvantages. A system optimization program using dynamic programming algorithm has been developed to calibrate the control parameters used in the developed control strategy, so that the control performance can be as close to the optimal solution as possible. In order to determine the sensitivity of the new control strategy to different driving conditions, a passenger car is simulated on different driving cycles. The performances of the vehicle with the new control strategy are compared with the optimal solution obtained on each driving condition with the dynamic programming optimization. The simulation result shows that the new control strategy always keeps its performance close to the optimal one, as the driving condition changes.
Advisors/Committee Members: Ehsani, Mehrdad (advisor), Singh, Chanan (committee member), Bhattacharyya, Shankar (committee member), jong%22%29&pagesize-30">
Kim,
Won-
jong (committee member).
Subjects/Keywords: Control strategy; Dynamic programming; Hybrid electric vehicle
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lai, L. (2013). A Development of Design and Control Methodology for Next Generation Parallel Hybrid Electric Vehicle. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/149289
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):
Lai, Lin. “A Development of Design and Control Methodology for Next Generation Parallel Hybrid Electric Vehicle.” 2013. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/149289.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Lai, Lin. “A Development of Design and Control Methodology for Next Generation Parallel Hybrid Electric Vehicle.” 2013. Web. 19 Feb 2019.
Vancouver:
Lai L. A Development of Design and Control Methodology for Next Generation Parallel Hybrid Electric Vehicle. [Internet] [Thesis]. Texas A&M University; 2013. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/149289.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Lai L. A Development of Design and Control Methodology for Next Generation Parallel Hybrid Electric Vehicle. [Thesis]. Texas A&M University; 2013. Available from: http://hdl.handle.net/1969.1/149289
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
22.
Rana, Dibyendu.
Analysis & Design of Active Inductor.
Degree: 2014, Texas A&M University
URL: http://hdl.handle.net/1969.1/152536
► Power conditioning topologies such as adjustable speed drives (ASDs) have a growing demand in industry for improving efficiency and reducing energy costs. Apart from efficiency…
(more)
▼ Power conditioning topologies such as adjustable speed drives (ASDs) have a growing demand in industry for improving efficiency and reducing energy costs. Apart from efficiency improvement, the power density of these converters has increased considerably and a smaller form factor is preferred by modern industrial plants. Power converters produce unwanted harmonics which deteriorate the grid current quality. To mitigate the adverse effects of such harmonics, filtering techniques such as active/passive filters and harmonic traps are employed. Passive inductors play an important role in these filtering topologies. However, in higher power/utility scale power conversion systems, due to lower switching frequency, the size and weight of passive inductor is large and they occupy considerable space. In industries such as offshore oil drilling and maritime transportation, size and weight requirements are strict and such bulky solutions are not desirable.
For such applications, an effective way to make passive components compact is to emulate using active devices. In this thesis, design of an Active Inductor for high power applications using an H-bridge topology is proposed. The performance of common filtering topologies such as LC and LCL with Active Inductor replacing a passive inductor is analyzed. The proposed topology emulates an inductance value which is linear for a wide range of operation, devoid of saturation issues and is compact in size and weight. Weight and volume analysis is done for an active topology and compared with equivalent passive inductors. It is shown that the emulated inductor is about 8 times lighter than a passive inductor of similar rating. Also, loss analysis proves that the topology has a high Q factor. A Zero Voltage Switching (ZVS) switching method is proposed to reduce switching losses further.
In addition, the dynamic behavior of the Active Inductor improves system performance during faults and disturbances. The value of inductance can be tuned to suit the requirements of the overall power conditioning circuit. The Active Inductor is shown to limit the current and voltage overshoots occurring due to faults. Simulation and experimental results from a laboratory prototype confirm the validity and utility of the proposed topology.
Advisors/Committee Members: Enjeti, Prasad (advisor), Balog, Robert (committee member), Bhattacharyya, Shankar (committee member), Jong%22%29&pagesize-30">
Kim,
Won-
Jong (committee member).
Subjects/Keywords: power density; emulation
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Rana, D. (2014). Analysis & Design of Active Inductor. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/152536
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):
Rana, Dibyendu. “Analysis & Design of Active Inductor.” 2014. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/152536.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Rana, Dibyendu. “Analysis & Design of Active Inductor.” 2014. Web. 19 Feb 2019.
Vancouver:
Rana D. Analysis & Design of Active Inductor. [Internet] [Thesis]. Texas A&M University; 2014. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/152536.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Rana D. Analysis & Design of Active Inductor. [Thesis]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/152536
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
23.
Albader, Mesaad.
Advance Three Phase Power Factor Correction Schemes for Utility Interface of Power Electronic Systems.
Degree: 2014, Texas A&M University
URL: http://hdl.handle.net/1969.1/153331
► Modern power electronic systems operate with different voltage and/or frequency rating such as Adjustable speed drive, Micro Grid, Uninterruptable Power Supplies (UPS) and High Voltage…
(more)
▼ Modern power electronic systems operate with different voltage and/or frequency rating such as Adjustable speed drive, Micro Grid, Uninterruptable Power Supplies (UPS) and High Voltage DC Transmission Systems. To match power electronic systems with the mains supply, DC link converters are used. The first stage of the DC link converter is the AC/DC conversion (rectifier). The rectifier type utility interface has substantial harmonics result in poor power quality due to low power factor and high harmonic distortion.
Power Factor Correction (PFC) schemes are effective methods to mitigate harmonics and address this issue. In this thesis, analyses of three approaches for high power density rectifiers are developed. In the first study, modular three phase boost rectifiers operating in DCM are coupled in order to increase the power density. Major drawback of this rectifier is the high currents ripple in both the source and the DC link sides which require large EMI filter size -could be larger than the rectifier component size- and large DC filter capacitor size. This thesis proposes coupling modular three phase boost DCM rectifiers, the currents in both source and DC link sides are interleaved and consequently the currents ripple dramatically decreased results in small component size of the EMI filter and the DC filter capacitor leading to high power density rectification. Also, optimization of the number of the rectifier modules to achieve maximum power density is presented. Moreover, the switching function of each rectifier employs harmonic injection technique to reduce the low order harmonics. And, the DC output voltage is varied with the load power such that the operation is at the boundary between CCM and DCM to achieve maximum power density tracking.
In the Second study, a resonant three phase single switch PFC is presented to overcome the high 5th and 7th order current harmonics drawback in the conventional single switch three phase PFC circuits. The input current has low THD for each individual low order harmonics with high current ripple at the switching frequency. Interleaving the input current by coupling modular rectifiers is also presented to reduce the input current ripple. System equations and modes of operation is analyzed and derived to design the circuit parameters, switching frequency and duty ratio for the desired output voltage and load power.
In the Third study, an advancement of existing modular T-connected single phase PFCs by means of replacing the low frequency transformer with medium frequency electronic phase shifter to reduce the size and weight of the system. The approach has higher power density compared with the Y, delta and T-connected single phase PFC modules. The study examines the 3 to 2 phase conversion, system harmonics, switching technique for the AC chopper and the power flow of the system.
Advisors/Committee Members: Enjeti, Prasad (advisor), Toliyat, Hamid (advisor), Bhattacharyya, Shankar (committee member), Jong%22%29&pagesize-30">
Kim,
Won-
Jong (committee member).
Subjects/Keywords: Three Phase; PFC; Power Factor Correction; Rectifier; AC/DC Conversion; Utility Interface; Power Electronics; Harmonic Suppression
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Albader, M. (2014). Advance Three Phase Power Factor Correction Schemes for Utility Interface of Power Electronic Systems. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/153331
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):
Albader, Mesaad. “Advance Three Phase Power Factor Correction Schemes for Utility Interface of Power Electronic Systems.” 2014. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/153331.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Albader, Mesaad. “Advance Three Phase Power Factor Correction Schemes for Utility Interface of Power Electronic Systems.” 2014. Web. 19 Feb 2019.
Vancouver:
Albader M. Advance Three Phase Power Factor Correction Schemes for Utility Interface of Power Electronic Systems. [Internet] [Thesis]. Texas A&M University; 2014. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/153331.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Albader M. Advance Three Phase Power Factor Correction Schemes for Utility Interface of Power Electronic Systems. [Thesis]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/153331
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
24.
Cheng, Yu-Che.
A Hybrid Brain-computer Interface for Intelligent Prosthetics.
Degree: 2014, Texas A&M University
URL: http://hdl.handle.net/1969.1/153806
► Over the past few decades, many researcher have shown that human can use brain signals to communicate with computers or machines by using brain-computer interfaces…
(more)
▼ Over the past few decades, many researcher have shown that human can use brain signals to communicate with computers or machines by using brain-computer interfaces (BCIs). BCI systems can measure the brain activity and translate them into control signals to external devices. A hybrid BCI system is to integrate two or more different BCI systems. By combining two different BCIs, the disadvantages can be eliminated and the advantages can stay.
One of the BCI developed in this thesis is electroencephalographic (EEG). EEG is one of imaging techniques for spontaneous recording of the electrical activity from the brain. The EEG has been widely used in research for cognitive and brain-state studies in psychology, neuroprosthetics, transportation safety and clinical diagnosis . In this thesis a commercial EEG product, NeuroSky MindWave, is used to measure the EEG signal from forehead. From the acquired EEG signal, humans attention and meditation level can be obtain. A EEG control algorithm is developed in LabVIEW based on the attention level, meditation level and eye blinks to control an intelligent prosthetic.
The other BCI used is eye-gaze tracking technology. Eye-gaze tracking technology is used to obtain the human's gaze direction. A eye-gaze tracking system is developed in this research. The system consists of a wearable self-build eye-gaze tracker with a scene camera, and the eye-gaze tracking algorithm developed in LabVIEW which can locate the eye pupil center and estimate the gaze direction.
Combing two BCIs above, a hybrid BCI system is complete. Suppose a person want to use a prosthetic arm to grab one specific item, the eye-gaze tracker provides the information of which item is the person want exactly, and EEG BCI controls the prosthetic arm to grasp the item. The hybrid BCI system is robust enough and have a reliable accuracy from the experimental result.
Advisors/Committee Members: Langari, Reza (advisor), Jong%22%29&pagesize-30">
Kim,
Won-
Jong (committee member),
Song, Dezhen (committee member).
Subjects/Keywords: Eye tracking; EEG; Brain-computer interface
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Cheng, Y. (2014). A Hybrid Brain-computer Interface for Intelligent Prosthetics. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/153806
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):
Cheng, Yu-Che. “A Hybrid Brain-computer Interface for Intelligent Prosthetics.” 2014. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/153806.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Cheng, Yu-Che. “A Hybrid Brain-computer Interface for Intelligent Prosthetics.” 2014. Web. 19 Feb 2019.
Vancouver:
Cheng Y. A Hybrid Brain-computer Interface for Intelligent Prosthetics. [Internet] [Thesis]. Texas A&M University; 2014. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/153806.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Cheng Y. A Hybrid Brain-computer Interface for Intelligent Prosthetics. [Thesis]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/153806
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
25.
Guerrero, Roberto.
Low-cost Rigid-frame Exoskeleton Glove with Finger-joint Flexion Tracking Mapped onto a Robotic Hand.
Degree: 2015, Texas A&M University
URL: http://hdl.handle.net/1969.1/155298
► This thesis provides a representation of a low-cost rigid-frame exoskeleton glove that is used to track finger-joint flexion mapped onto a robotic hand to mimic…
(more)
▼ This thesis provides a representation of a low-cost rigid-frame exoskeleton glove that is used to track finger-joint flexion mapped onto a robotic hand to mimic user movements. The overall setup consists of an exoskeleton glove (exo-glove), sensors, a microcontroller, and a telerobotic hand. The design of the exo-glove is crafted to fit onto a left hand. SolidWorks was used for the prototype designs which were then sent to the Stratasys 400 rapid prototyping machine to be 3D printed in ABS-M30 plastic.
The exo-glove houses five rotary position sensors and three flexible sensors to track angle changes of the finger joints from two fingers and a thumb. Five low-pass filters are implemented as signal filtering for the rotary position sensors. An Arduino Mega microcontroller is connected to the sensors of the exo-glove and processes the input values. Using an open-loop controller to control the robotic hand, the values processed by the microcontroller from the exo-glove are sent to the servo motors on the robotic hand to operate the corresponding fingers of the user.
Throughout the initial calibration and testing phase, each sensor was tested individually to ensure the sensor functionally performs well. Signal analysis was conducted on the sensors at steady state and while in operation to show fluctuations in sensor readings and response to finger flexion. Experimental results show that averaging sensor data in the processing code yields smoother values and better precision. Due to the use of low-pass filtering with the rotary position sensors, the data sets collected were grouped together tightly compared to the flex sensors without filtering. However, the actual angles measured were not accurately portrayed in sensor readings. The true flexion angles were compared in the data samplings to find a variety of ranges spanning around the angles desired to track. Many of the actual flexion angles were offset from the sensor readings by a variation of degrees, but the data shows the sensor readings were able to follow the general magnitude of the true flexion angles.
The precision seen in the data was also apparent in the robotic hand mirroring the posture. Changes in sensor readings caused jerking movements to occur in the robotic fingers but were able to maintain an overall flexion mirroring of the RF exo-glove. There is quarter-second delay between the exo-glove sensor reading and the robotic hand mirroring capability when not implementing averaging. When averaging the sensor values, there was a delay of more than half a second between the exo-glove posture and robotic hand mirroring.
Advisors/Committee Members: jong%22%29&pagesize-30">
Kim,
Won-
jong (advisor),
Ehsani, Mehrdad (committee member),
McAdams, Daniel (committee member).
Subjects/Keywords: exo-glove; exoskeleton glove; flex sensors; rotary position sensors; rigid frame glove; finger flexion tracking; hand tracking; hand rehabilitation; finger rehabilitation
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Guerrero, R. (2015). Low-cost Rigid-frame Exoskeleton Glove with Finger-joint Flexion Tracking Mapped onto a Robotic Hand. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/155298
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):
Guerrero, Roberto. “Low-cost Rigid-frame Exoskeleton Glove with Finger-joint Flexion Tracking Mapped onto a Robotic Hand.” 2015. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/155298.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Guerrero, Roberto. “Low-cost Rigid-frame Exoskeleton Glove with Finger-joint Flexion Tracking Mapped onto a Robotic Hand.” 2015. Web. 19 Feb 2019.
Vancouver:
Guerrero R. Low-cost Rigid-frame Exoskeleton Glove with Finger-joint Flexion Tracking Mapped onto a Robotic Hand. [Internet] [Thesis]. Texas A&M University; 2015. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/155298.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Guerrero R. Low-cost Rigid-frame Exoskeleton Glove with Finger-joint Flexion Tracking Mapped onto a Robotic Hand. [Thesis]. Texas A&M University; 2015. Available from: http://hdl.handle.net/1969.1/155298
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
26.
Nguyen, Vu Huy.
Universal Framework for Linear Motors and Multi-Axis Stages with Magnetic Levitation.
Degree: 2015, Texas A&M University
URL: http://hdl.handle.net/1969.1/156534
► This dissertation presents the electromagnetic design and experimental validation of a new framework for linear permanent-magnet (PM) machines with targeted applications in precision motion control.…
(more)
▼ This dissertation presents the electromagnetic design and experimental validation of a new framework for linear permanent-magnet (PM) machines with targeted applications in precision motion control. In this framework, a single forcer, which can generate two independent force components in two perpendicular directions, consists of a stationary Halbach magnet array and two Lorentz coils with a phase difference of 90? or 270?. Any number of coil pairs can be attached on the same moving frame to work with a common magnet array or matrix, forming a linear or planar PM motor. Key advantages of this framework are simple force calculation, a linear system model, and a reduced number of coils for force generation and allocation in multi-axis positioners. The proposed framework effectively allows for decoupled dynamics, simplifying the linear controller design and real-time implementation.
To experimentally verify the theoretical framework proposed herein, a high-precision 6-axis magnetically levitated (maglev) stage is designed, constructed, and controlled. The development of this 6-axis positioning system is an integrated work, including magnetic-force calculation and analysis, mechanical design, fabrication, assembly, system modeling, system identification, and control system design. The mechanical components of the system include a stationary superimposed Halbach magnet matrix, which was previously built, and a moving platen with a plastic frame, four sets of 2-phase coils, and two precision mirrors. For position measurements, there are three laser interferometers for in-plane position measurements, three laser displacement sensors for out-of-plane position sensing, and two 2-channel Hall-effect sensors for the position feedback to initialize the position and expand the travel ranges of the platen in the XY plane.
The positioning resolutions of 10 nm in the xy plane and in the vertical axis are demonstrated. In out-of-plane rotation about the two horizontal axes, experimental results show the unprecedented positioning resolution of 0.1 ?rad. The maximum travel range in X and Y with nanoscale positioning resolution is 56 mm ? 35 mm, limited by the lengths of the precision mirrors attached to the platen. With the trapezoidal-velocity input shaping, achieved performance specifications include the maximum acceleration and velocity of 0.6
m/s2 and 0.06
m/s, respectively, in translations in the horizontal plane. With the platen supported by the air bearings, the maximum acceleration and speed are 1.5
m/s2 and 0.15
m/s, respectively. A load test is performed with the platen carrying a load of 0.54 kg, which is 72% of its total mass, magnetically levitated in 6- axis closed-loop control. Experimental results show the reduced coupled dynamics between different axes in magnetic levitation. This framework of 2-phase Lorentz coils and linear Halbach arrays is highly applicable in precision-positioning linear motors and multi-axis stages, steppers, scanners, nano-scale manipulation and alignment systems, and vibration isolators.
Advisors/Committee Members: jong%22%29&pagesize-30">
Kim,
Won-
jong (advisor),
Langari, Reza (committee member),
Palazzolo, Alan (committee member),
Toliyat, Hamid (committee member).
Subjects/Keywords: Magnetic Levitation; Nanopositioning; Halbach Array; Positioning Stage; Mechatronics; Motion Control
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Nguyen, V. H. (2015). Universal Framework for Linear Motors and Multi-Axis Stages with Magnetic Levitation. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/156534
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):
Nguyen, Vu Huy. “Universal Framework for Linear Motors and Multi-Axis Stages with Magnetic Levitation.” 2015. Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/156534.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Nguyen, Vu Huy. “Universal Framework for Linear Motors and Multi-Axis Stages with Magnetic Levitation.” 2015. Web. 19 Feb 2019.
Vancouver:
Nguyen VH. Universal Framework for Linear Motors and Multi-Axis Stages with Magnetic Levitation. [Internet] [Thesis]. Texas A&M University; 2015. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/156534.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Nguyen VH. Universal Framework for Linear Motors and Multi-Axis Stages with Magnetic Levitation. [Thesis]. Texas A&M University; 2015. Available from: http://hdl.handle.net/1969.1/156534
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
27.
Tong, Xiaomeng.
Nonlinear Prediction of Thermally Induced Rotor Instability (Morton Effect) and Experiment Verification.
Degree: PhD, Mechanical Engineering, 2018, Texas A&M University
URL: http://hdl.handle.net/1969.1/174639
► The Morton effect (ME) is a thermally induced rotor instability problem that most commonly appears in rotating shafts with large overhung masses and supported by…
(more)
▼ The Morton effect (ME) is a thermally induced rotor instability problem that most commonly appears in rotating shafts with large overhung masses and supported by fluid film bearings. The time-varying thermal bow, due to the asymmetric journal temperature distribution, may cause intolerable synchronous vibrations that exhibit a hysteresis behavior with respect to rotor speed. First discovered by Morton in the 1970s, and theoretically analyzed by Keogh and Morton in the 1990s, the ME is still not fully understood by industry and academia experts. Traditional rotordynamic analysis generally fails to predict the potential existence of ME induced instability in the design stage or troubleshooting process, and the induced excessive rotor vibrations cannot be effectively suppressed through conventional balancing, due to the continuous fluctuation of vibration amplitude and phase angle. The early ME prediction methodologies adopt three assumptions which simplify the ME analysis and meanwhile reduce its accuracy in predicting the ME response. (1) The ME is assumed to be static and speed-dependent and thus its stability can be analyzed with the classic control theories in the frequency (speed) domain. Nevertheless, the ME is proven to be highly transient and process-oriented, and not only the operating speed but also the transient speed acceleration can cause instability. (2) The thermal bow effect is only considered at the rotor overhung side and is simplified with thermal imbalance, which neglects the ME induced thermal bending moment. (3) Early ME prediction only focuses on the single rotor-bearing side and neglects the coupled effect on rotordynamics and bearing behavior from the other side. The assumptions above are abandoned in the current dissertation and replaced with the high-fidelity transient finite element analysis (FEA). The FEA is based on the recent thermo-elasto-hydro-dynamic bearing analysis and featured with (1) the nonlinear transient prediction of ME in the time domain through numerical integration, (2) analyzing both rotor-bearing sides to simultaneously account for the overall thermal bow effect, and thus the coupled rotordynamics effect from both rotor-bearing sides can be considered, and (3) the bowed rotor method, which also considers the thermal bow at the rotor midspan besides the rotor ends. The thermal bending moment is also included in the rotordynamics model, making this method more accurate than the traditional thermal imbalance method. Moreover, the ME testing rig is designed to measure the temperature distribution with 20 sensors across the journal circumference and record the peak-peak temperature difference (?T) with respect to various operating conditions. Supply oil temperatures of 28℃, 41℃ and bearing eccentricity of 0, 32%Cb are tested with rotating speed up to 5500 rpm. The journal ?T is found to increase almost linearly with speed up to 5500 rpm, slightly increase with eccentricity from 0 to 32%Cb, and decrease by nearly 20% by raising the supply temperature from 28℃ to 41℃ due to…
Advisors/Committee Members: Palazzolo, Alan (advisor), Jong%22%29&pagesize-30">
Kim,
Won-
Jong (committee member),
Suh, Steve (committee member),
Falzarano, Jeffrey (committee member).
Subjects/Keywords: Thermally Induced Instability; Morton Effect; Tilting Pad Bearing; Finite Element Method.
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Tong, X. (2018). Nonlinear Prediction of Thermally Induced Rotor Instability (Morton Effect) and Experiment Verification. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/174639
Chicago Manual of Style (16th Edition):
Tong, Xiaomeng. “Nonlinear Prediction of Thermally Induced Rotor Instability (Morton Effect) and Experiment Verification.” 2018. Doctoral Dissertation, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/174639.
MLA Handbook (7th Edition):
Tong, Xiaomeng. “Nonlinear Prediction of Thermally Induced Rotor Instability (Morton Effect) and Experiment Verification.” 2018. Web. 19 Feb 2019.
Vancouver:
Tong X. Nonlinear Prediction of Thermally Induced Rotor Instability (Morton Effect) and Experiment Verification. [Internet] [Doctoral dissertation]. Texas A&M University; 2018. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/174639.
Council of Science Editors:
Tong X. Nonlinear Prediction of Thermally Induced Rotor Instability (Morton Effect) and Experiment Verification. [Doctoral Dissertation]. Texas A&M University; 2018. Available from: http://hdl.handle.net/1969.1/174639

Texas A&M University
28.
Zhang, Xiaohua.
Small Engine Flash Vapor JP-8 Fuel Injector Testing, Simulation and Development.
Degree: PhD, Mechanical Engineering, 2014, Texas A&M University
URL: http://hdl.handle.net/1969.1/174186
► Following U.S. Army’s single fuel initiative, Wankel rotary engines used in U.S. Army’s shadow unmanned aerial vehicles (UAVs) need to be retrofitted from running on…
(more)
▼ Following U.S. Army’s single fuel initiative, Wankel rotary engines used in U.S. Army’s shadow unmanned aerial vehicles (UAVs) need to be retrofitted from running on aviation gasoline (AVGAS) to JP-8. The feasibility of retrofitting the engine with a flash vapor direct fuel injector was investigated. A commercial off-the-shelf direct fuel injector was used in the study. A photo detector measurement tool was developed to measure high frequency (>100 Hz) injection event. A coupled electrical-electomagnetics-fluid-mechanical system was simulated to understand the pintle dynamics during an injection event. Optimal injector power drive was revealed to be a multi-stage current profile. A flash heater was designed and tested to be capable of heating up JP-8 from room temperature to its vaporization temperature (>310F) under one tenth of a second at the required flow rate. An ignition test rig was built to compare ignition behavior between AVGAS and heated JP-8. Test result showed that the 550F pre-heated JP-8 had equal or superior ignition pressure rise / ignition delay time than AVGAS.
Advisors/Committee Members: Palazzolo, Alan (advisor), jong%22%29&pagesize-30">
Kim,
Won-
jong (committee member),
Petersen, Eric (committee member),
Toliyat, Hamid (committee member).
Subjects/Keywords: fuel injector; flash heating; JP-8; Wankel rotary engine; multi-physics modeling; spray measurement; ignition test
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zhang, X. (2014). Small Engine Flash Vapor JP-8 Fuel Injector Testing, Simulation and Development. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/174186
Chicago Manual of Style (16th Edition):
Zhang, Xiaohua. “Small Engine Flash Vapor JP-8 Fuel Injector Testing, Simulation and Development.” 2014. Doctoral Dissertation, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/174186.
MLA Handbook (7th Edition):
Zhang, Xiaohua. “Small Engine Flash Vapor JP-8 Fuel Injector Testing, Simulation and Development.” 2014. Web. 19 Feb 2019.
Vancouver:
Zhang X. Small Engine Flash Vapor JP-8 Fuel Injector Testing, Simulation and Development. [Internet] [Doctoral dissertation]. Texas A&M University; 2014. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/174186.
Council of Science Editors:
Zhang X. Small Engine Flash Vapor JP-8 Fuel Injector Testing, Simulation and Development. [Doctoral Dissertation]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/174186

Texas A&M University
29.
Eib, Andrew.
Design of a Backdrivable Upper-Limb Exoskeleton for Use in Rehabilitation Therapy of Stroke Patients.
Degree: MS, Mechanical Engineering, 2018, Texas A&M University
URL: http://hdl.handle.net/1969.1/173937
► The topic of this thesis is the development of a highly backdrivable exoskeleton for use in rehabilitation therapy of stroke patients. A synthetic rope drive…
(more)
▼ The topic of this thesis is the development of a highly backdrivable exoskeleton for use in rehabilitation therapy of stroke patients. A synthetic rope drive actuator, called a capstan drive, is developed and tested. An exoskeleton is developed using 7 capstan drives.
Each capstan drive is tailored for its load conditions. A total of 8 Degrees of Freedom (DOF) are available, with 5 DOFs used to replicate four degrees of freedom of the shoulder joint: flexion & extension, abduction & adduction, medial & lateral rotation, and elevation & depression. The last three DOFs are elbow extension & flexion, pronation & supination of the forearm, and open the patient’s hand.
FEA analysis is used to validate the mechanical structural integrity of the system and all components are machined and built. Results from initial testing show that the exoskeleton functions as expected and is ready for implementation of advanced controls algorithms. In conclusion, the backdrivable exoskeleton was a success, future designers may wish to include niceties such as an electromagnetic brakes on each drive unit.
Advisors/Committee Members: Langari, Reza (advisor), Jong%22%29&pagesize-30">
Kim,
Won-
Jong (committee member),
Johnson, Michael D (committee member).
Subjects/Keywords: Capstan Drive; Backdrivable; exoskeleton; Upper-limb; stroke rehabilitation; stroke robotics
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MLA ·
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APA (6th Edition):
Eib, A. (2018). Design of a Backdrivable Upper-Limb Exoskeleton for Use in Rehabilitation Therapy of Stroke Patients. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/173937
Chicago Manual of Style (16th Edition):
Eib, Andrew. “Design of a Backdrivable Upper-Limb Exoskeleton for Use in Rehabilitation Therapy of Stroke Patients.” 2018. Masters Thesis, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/173937.
MLA Handbook (7th Edition):
Eib, Andrew. “Design of a Backdrivable Upper-Limb Exoskeleton for Use in Rehabilitation Therapy of Stroke Patients.” 2018. Web. 19 Feb 2019.
Vancouver:
Eib A. Design of a Backdrivable Upper-Limb Exoskeleton for Use in Rehabilitation Therapy of Stroke Patients. [Internet] [Masters thesis]. Texas A&M University; 2018. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/173937.
Council of Science Editors:
Eib A. Design of a Backdrivable Upper-Limb Exoskeleton for Use in Rehabilitation Therapy of Stroke Patients. [Masters Thesis]. Texas A&M University; 2018. Available from: http://hdl.handle.net/1969.1/173937

Texas A&M University
30.
Shin, Sungtae.
Myoelectric Human Computer Interaction Using Reliable Temporal Sequence-based Myoelectric Classification for Dynamic Hand Gestures.
Degree: PhD, Mechanical Engineering, 2016, Texas A&M University
URL: http://hdl.handle.net/1969.1/174271
► To put a computerized device under human control, various interface techniques have been commonly studied in the realm of Human Computer Interaction (HCI) design. What…
(more)
▼ To put a computerized device under human control, various interface techniques have been commonly studied in the realm of Human Computer Interaction (HCI) design. What this dissertation focuses on is a myoelectric interface, which controls a device via neuromuscular electrical signals. Myoelectric interface has advanced by recognizing repeated patterns of the signal (pattern recognition-based myoelectric classification). However, when the myoelectric classification is used to extract multiple discrete states within limited muscle sites, there are robustness issues due to external conditions: limb position changes, electrode shifts, and skin condition changes. Examined in this dissertation is the robustness issue, or drop in the performance of the myoelectric classification when the limb position varies from the position where the system was trained.
Two research goals outlined in this dissertation are to increase reliability of myoelectric system and to build a myoelectric HCI to manipulate a 6-DOF robot arm with a 1-DOF gripper. To tackle the robustness issue, the proposed method uses dynamic motions which change their poses and configuration over time. The method assumes that using dynamic motions is more reliable, vis-a-vis the robustness issues, than using static motions. The robustness of the method is evaluated by choosing the training sets and validation sets at different limb positions. Next, an HCI system manipulating a 6-DOF robot arm with a 1-DOF gripper is introduced. The HCI system includes an inertia measurement unit to measure the limb orientation, as well as EMG sensors to acquire muscle force and to classify dynamic motions. Muscle force and the orientation of a forearm are used to generate velocity commands. Classified dynamic motions are used to change the manipulation modes. The performance of the myoelectric interface is measured in terms of real-time classification accuracy, path efficiency, and time-related measures.
In conclusion, this dissertation proposes a reliable myoelectric classification and develops a myoelectric interface using the proposed classification method for an HCI application. The robustness of the proposed myoelectric classification is verified as compared to previous myoelectric classification approaches. The usability of the developed myoelectric interface is compared to a well-known interface.
Advisors/Committee Members: Langari, Reza (advisor), Tafreshi, Reza (advisor), jong%22%29&pagesize-30">
Kim,
Won-
jong (committee member),
Choe, Yoonsuck (committee member).
Subjects/Keywords: Human Computer Interaction (HCI); myoelectric classification; myoelectric interface
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share





❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Shin, S. (2016). Myoelectric Human Computer Interaction Using Reliable Temporal Sequence-based Myoelectric Classification for Dynamic Hand Gestures. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/174271
Chicago Manual of Style (16th Edition):
Shin, Sungtae. “Myoelectric Human Computer Interaction Using Reliable Temporal Sequence-based Myoelectric Classification for Dynamic Hand Gestures.” 2016. Doctoral Dissertation, Texas A&M University. Accessed February 19, 2019.
http://hdl.handle.net/1969.1/174271.
MLA Handbook (7th Edition):
Shin, Sungtae. “Myoelectric Human Computer Interaction Using Reliable Temporal Sequence-based Myoelectric Classification for Dynamic Hand Gestures.” 2016. Web. 19 Feb 2019.
Vancouver:
Shin S. Myoelectric Human Computer Interaction Using Reliable Temporal Sequence-based Myoelectric Classification for Dynamic Hand Gestures. [Internet] [Doctoral dissertation]. Texas A&M University; 2016. [cited 2019 Feb 19].
Available from: http://hdl.handle.net/1969.1/174271.
Council of Science Editors:
Shin S. Myoelectric Human Computer Interaction Using Reliable Temporal Sequence-based Myoelectric Classification for Dynamic Hand Gestures. [Doctoral Dissertation]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/174271
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