Mobile Robotic System for Ground-Testing of Multi-Spacecraft Proximity Operations

Abstract

Ground testing of multi-spacecraft proximity operations with hardware in-theloop is currently an expensive and challenging process. We present our approach to this problem, applicable to proximity operations of small spacecraft.We are developing a novel autonomous mobile robotic system to emulate full 6 degree of freedom relative motion at high fidelity. An omni-directional base provides large 3-DOF motion with moderate precision, while a micron-class Stewart platform on top provides high precision, limited 6-DOF motion. This multi-vehicle robotic system is designed to accommodate multiple untethered vehicles simultaneously, allowing for the real-time emulation of relative motion for a large variety of multi-spacecraft proximity operations.Compared with other facilities with similar goals, this approach will allow greater freedom of motion at a target operating cost much lower than existing facilities. We believe these capabilities will be invaluable to the growing number of small and micro satellite programs.

Two-leveled obstacle avoidance scheme using a kinematically redundant omni-directional mobile robot

“…This mobile robot also has kinematic redundancy but it is not omni-directional. Davis, et al [12] proposed a mobile robotic system for ground-testing of multi-spacecraft proximity operations. This mobile robot incorporated a 6 DOF parallel robot on the platform to provide kinematic redundancy in the operational space, but not in the wheel chain.…”