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Dynamic Modeling & Prediction

Efficient Trajectory Prediction for Satellites Subject to Atmospheric Drag

Collaborator: Dr. Ryan Weisman, Research Aerospace Engineer, Space Vehicles Directorate, Air Force Research Laboratory
March 2014 - Current

This research deals with application of singular perturbation methods to better characterize the motion of objects in low Earth orbit that are subjected to atmospheric drag. The impact of drag during changing solar conditions can significantly impact the ability to precisely predict the spacecraft trajectory along with orbit lifetime. During solar storms of high solar conditions, orbit lifetimes can decrease from months to weeks compared to low solar activity. By utilizing fundamental perturbation techniques and properly posing the problem, the computation time of orbit trajectory was decreased by 10 times compared with conventional numerical integration while maintaining numerical precision of numerical integration. This decrease in computation time allows a more robust method of uncertainty characterization of low Earth orbit trajectories especially during times of high solar activity, making it possible to reduce the risk of impact with other objects, which would most likely result in loss of the spacecraft.

Working with me on this research is my graduate research assistant, Armand Issam Awad. Armand was selected as the 2014 and 2015 AFRL Space Research Scholar for this research.

Related publication: Awad, Armand, Narang-Siddarth, Anshu, and Weisman, Ryan. 2016 “The Method of Multiple Scales for Orbit Propagation with Atmospheric Drag”, Guidance, Navigation, and Control: Spacecraft Guidance, Navigation and Control, AIAA SciTech, San Diego, CA.