Low-Complexity Spacecraft Guidance Using Artificial Potential Functions

An inspection mission of a non-maneuvering target in circular Earth orbit by a chase vehicle (the "Inspector") using potential function guidance (PFG) is considered. A simulation of obstacle avoidance by the Inspector are first shown to demonstrate the method. Simulations of the Inspector approaching the target from a stand-off waiting point to close-in inspections and target fly-arounds are then shown. The chaser is assumed to be a constrained vehicle limited to COTS components with parameters similar to that of SNAP-1, a successful demonstrator of a target rendezvous and inspection by a nanosatellite. Navigation inaccuracies, actuation limits and uncertainties are incorporated into the mathematical model to examine the robustness of PFG for this application. It is shown that PFG is robust to these uncertainties while also providing the agility required for such missions using a very simple guidance philosophy.