On-Ground Validation of Orbital GNC: Visual Navigation Assessment in Robotic Testbed Facility

CubeSats have become versatile platforms for various space missions (e.g. On-Orbit Servicing and debris removal), owing to their low cost and flexibility. Many of these tasks involve proximity operations, requiring precise guidance, navigation, and control (GNC) algorithms. Vision-based navigation is gaining traction for such operations, but extreme lighting conditions in space challenge optical techniques. This paper presents the ground validation of a GNC algorithm designed for autonomous satellite rendezvous, leveraging hardware-in-the-loop (HIL) experiments. The investigation focuses on two key areas. Firstly, the rationale behind the augmenting of the robot workspace (6-Dof UR10e robot + linear rail) to emulate relatively longer trajectories with complete position and orientation states. Secondly, the assessment of the control algorithm in response to uncertain pose observations from the vision-based navigation system. Results indicate increased control costs with uncertain navigation and exemplify the importance of on-ground testing for system validation prior to launch, especially in extreme cases that are typically difficult with software-based testing.