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One of the most promising solutions to the issue of the increasing amount of space debris orbiting the Earth is net-based Active Debris Removal. For accurate contact detection of thin target geometries with lumped-parameter modeled nets in simulations, many nodes (possibly 10 or more) must be introduced along threads. However, such introduction significantly increases the computational cost of simulations. This work proposes a modeling approach that introduces additional nodes during the deployment phase of the simulation rather than at the beginning to reduce such costs. The approach conserves the net’s total linear momentum and adheres to the work-energy principle when employed mid-simulation. Through both quantitative and qualitative comparisons of nets with and without model switching, this work demonstrates that the methodology does not alter the overall dynamics of the net flight toward the target in a significant way. Capture simulations of a scaled-down Envisat satellite model are performed, where the introduction of model switching results in approx. 2.45 times faster simulation without compromising accuracy in the representation of capture.
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Validation of Models for Net Deployment and Capture Simulation with Experimental Data
This work validates lumped-parameter models and cable-based models for nets against data from a parabolic flight experiment. The capabilities of a simulator based in Vortex Studio, a multibody dynamics simulation framework, are expanded by introducing i) a lumped-parameter model of the net with lumped masses placed along the threads and ii) a flexible-cable-based model, both of which enable collision detection with thin bodies. An experimental scenario is recreated in simulation, and the deployment and capture phases are analyzed. Good agreement with experiments is observed in both phases, although with differences primarily due to imperfect knowledge of experimental initial conditions. It is demonstrated that both a lumped-parameter model with inner nodes and a cable-based model can enable the detection of collisions between the net and thin geometries of the target. While both models improve notably capture realism compared to a lumped parameter model with no inner nodes, the cable-based model is found to be most computationally efficient. The effect of modeling thread-to-thread collisions (i.e., collisions among parts of the net) is analyzed and determined to be negligible during deployment and initial target wrapping. The results of this work validate the models and increase the confidence in the practicality of this simulator as a tool for research on net-based capture of debris. A cable-based model is validated for the first time in the literature.
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- Award ID(s):
- 2128578
- PAR ID:
- 10457352
- Date Published:
- Journal Name:
- Journal of Spacecraft and Rockets
- ISSN:
- 0022-4650
- Page Range / eLocation ID:
- 1 to 19
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.2514/1.A35798
