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You searched for subject:(active debris removal). Showing records 1 – 2 of 2 total matches.

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University of Toronto

1. Hakima, Houman. A New Approach to Active Removal of Space Debris.

Degree: PhD, 2020, University of Toronto

As a result of human space activities for over sixty years, there exist numerous man-made debris objects in the Earth orbits. Such objects not only jeopardize current operations of important space assets, but can also seriously hinder future space missions through a potential chain reaction of colliding space debris. This research addresses mitigation and remediation of the space debris environment. The thesis entails research in four critical subject areas: i) characterization of the debris environment, ii) assessment of the active debris removal methods proposed in the literature, iii) detailed engineering of a novel removal concept using a CubeSat spacecraft, called Deorbiter CubeSat, for sizable debris objects in low-Earth orbit, and iv) design of attitude and orbit controllers for the proposed spacecraft. The research first develops a probabilistic method for the prioritization of debris objects to be consid- ered in near-future removal missions. Then, a comparative study and in-depth analysis is conducted on the removal methods proposed in the literature to investigate their viability, through a number of multi- criteria assessment techniques. A Monte Carlo analysis is used in the study to quantify the intrinsic uncertainty associated with the space debris population. Next, a new debris removal mission utilizing Deorbiter CubeSats is conceptualized, and the design of CubeSat subsystems is detailed. A mothership spacecraft carries and deploys a number of Deorbiter CubeSats into designated orbits near their target debris. Each CubeSat uses an eight-unit form factor, and consists of commercially-available components with substantial space heritage. The actual performance specifications of the components are used to examine the proposed space debris removal approach. Finally, control schemes are synthesized for the critical maneuvers in the mission, using a unilateral low-thrust propulsion and a three-axis reaction wheel systems onboard the CubeSat, namely, i) concurrent rendezvous and attitude synchronization maneuver for approaching and attaching to the debris, ii) detumbling maneuver for stabilizing the debris attitude motion, and iii) deorbiting maneuver for transferring the debris from its original orbit to a deorbit altitude along a time-optimal trajectory. Several numerical simulations verify and validate the proposed approach as well as the control schemes. Advisors/Committee Members: Emami, M. Reza, Aerospace Science and Engineering.

Subjects/Keywords: Active Debris Removal; Attitude and Orbit Control; Attitude Dynamics; Deorbiter CubeSat; Orbital Dynamics; Space Debris; 0538

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Hakima, H. (2020). A New Approach to Active Removal of Space Debris. (Doctoral Dissertation). University of Toronto. Retrieved from http://hdl.handle.net/1807/101359

Chicago Manual of Style (16th Edition):

Hakima, Houman. “A New Approach to Active Removal of Space Debris.” 2020. Doctoral Dissertation, University of Toronto. Accessed February 25, 2021. http://hdl.handle.net/1807/101359.

MLA Handbook (7th Edition):

Hakima, Houman. “A New Approach to Active Removal of Space Debris.” 2020. Web. 25 Feb 2021.

Vancouver:

Hakima H. A New Approach to Active Removal of Space Debris. [Internet] [Doctoral dissertation]. University of Toronto; 2020. [cited 2021 Feb 25]. Available from: http://hdl.handle.net/1807/101359.

Council of Science Editors:

Hakima H. A New Approach to Active Removal of Space Debris. [Doctoral Dissertation]. University of Toronto; 2020. Available from: http://hdl.handle.net/1807/101359

2. Hardy, Brian Patrick. Long-term effects of satellite megaconstellations on the debris environment in low earth orbit.

Degree: MS, Aerospace Engineering, 2020, University of Illinois – Urbana-Champaign

This thesis examines the potential long-term impacts of satellite megaconstellations in Low Earth Orbit, with a focus on how post-mission disposal rates for megaconstellations will affect their contributions to orbital debris over the next 150 years. A new, medium-fidelity simulation for modeling orbital debris is developed and described, and several test cases are run with SpaceX’s Starlink megaconstellation and varying success rates for post-mission disposal. In cases where Starlink’s post-mission disposal rate is insufficient to prevent debris growth, varying amounts of active debris removal are explored as a potential mitigation measure. It is shown that LEO debris levels will grow at almost double their baseline rate if Starlink meets only the minimum regulatory requirements for post-mission disposal, and even relatively high rates of active debris removal cannot always return the LEO environment to its non-megaconstellation baseline. Still, the potential exists to minimize the debris-generating effects of large megaconstellations like Starlink if post-mission disposal rates of 95% or better can be achieved. Advisors/Committee Members: Ho, Koki (advisor).

Subjects/Keywords: space debris; megaconstellations; active debris removal

…failure rate over time. 1.4 Active Debris Removal As megaconstellations insert potentially… …x5D;. One proposed solution is active debris removal, whereby specialpurpose spacecraft… …and legal difficulties, active debris removal could prove vital to preserving the future LEO… …study of orbital debris, megaconstellations, and active debris removal. Notable publications… …methods discussed previously. 16 2.5 Effects of Active Debris Removal Lastly, a significant… 

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Hardy, B. P. (2020). Long-term effects of satellite megaconstellations on the debris environment in low earth orbit. (Thesis). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/108004

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):

Hardy, Brian Patrick. “Long-term effects of satellite megaconstellations on the debris environment in low earth orbit.” 2020. Thesis, University of Illinois – Urbana-Champaign. Accessed February 25, 2021. http://hdl.handle.net/2142/108004.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Hardy, Brian Patrick. “Long-term effects of satellite megaconstellations on the debris environment in low earth orbit.” 2020. Web. 25 Feb 2021.

Vancouver:

Hardy BP. Long-term effects of satellite megaconstellations on the debris environment in low earth orbit. [Internet] [Thesis]. University of Illinois – Urbana-Champaign; 2020. [cited 2021 Feb 25]. Available from: http://hdl.handle.net/2142/108004.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Hardy BP. Long-term effects of satellite megaconstellations on the debris environment in low earth orbit. [Thesis]. University of Illinois – Urbana-Champaign; 2020. Available from: http://hdl.handle.net/2142/108004

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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