Concurrent Parameter Identification and Control for Free-Floating Robotic Systems During On-Orbit Servicing

To control a free-floating robotic system with uncertain parameters in OOS tasks with high accuracy, a fast parameter identification method, previously developed by the authors, is enhanced further and used concurrently with a controller. The method provides accurate parameter estimates, without any prior knowledge of any system dynamic properties. This control scheme compensates for the accumulated angular momentum on the reaction wheels (RWs), which acts as a disturbance to the robotic servicer base. While any controller using parameter information can be used, a transposed Jacobian controller, modified to include RW angular momentum disturbance rejection, is employed here. Threedimensional simulations demonstrate the method's validity.