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NASA NTRS · 20150023583

A Sampling Based Approach to Spacecraft Autonomous Maneuvering with Safety Specifications

Starek, Joseph A.·Barbee, Brent W.·Pavone, Marco
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Abstract

This paper presents a methods for safe spacecraft autonomous maneuvering that leverages robotic motion-planning techniques to spacecraft control. Specifically the scenario we consider is an in-plan rendezvous of a chaser spacecraft in proximity to a target spacecraft at the origin of the Clohessy Wiltshire Hill frame. The trajectory for the chaser spacecraft is generated in a receding horizon fashion by executing a sampling based robotic motion planning algorithm name Fast Marching Trees (FMT) which efficiently grows a tree of trajectories over a set of probabillistically drawn samples in the state space. To enforce safety the tree is only grown over actively safe samples for which there exists a one-burn collision avoidance maneuver that circularizes the spacecraft orbit along a collision-free coasting arc and that can be executed under potential thrusters failures. The overall approach establishes a provably correct framework for the systematic encoding of safety specifications into the spacecraft trajectory generations process and appears amenable to real time implementation on orbit. Simulation results are presented for a two-fault tolerant spacecraft during autonomous approach to a single client in Low Earth Orbit.

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Starek, Joseph A., Barbee, Brent W., Pavone, Marco. 2015-02-03. A Sampling Based Approach to Spacecraft Autonomous Maneuvering with Safety Specifications. https://ntrs.nasa.gov/citations/20150023583

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