Sliding mode control of space vehicle with dual-arm robotic manipulators for RPOD with non-collaborative target

In recent years, there have been significant enhancements in technologies related to space applications. Particularly, advancements have been made in space launch systems with substantial transport capabilities, demonstrating them as a reliable and reusable technology expected to dramatically reduce mission costs in the future. Such achievements represent a significant milestone in space exploration. For these reasons, the number of objects launched into space and currently orbiting Earth is expected to increase dramatically in a short period of time. Consequently, the likelihood of accidental collisions between servicing spacecraft and uncontrolled space resident objects (RSOs) may rise significantly. If effective measures to mitigate space debris are not implemented, the European Space Agency forecasts that one in every twenty five spacecraft could collide with space objects by 2030. Several approaches for recovering uncontrolled RSOs have been studied and developed, but a safe, reliable, and reusable solution remains essential and needs to be addressed carefully. Since robotic manipulators have successfully completed a variety of tasks, including assisting in berthing procedures, performing repetitive tasks, among others, they can be considered as a strong option for conducting on-orbit servicing. Therefore, there has been significant interest in their implementation in space missions, and ongoing research is being conducted to further explore their potential use. This thesis investigates the application of a super twisting sliding mode control technique on a dual-manipulator space vehicle. The system dynamics are formulated, and a control algorithm is implemented to handle the coupling between the robotic manipulators and the base spacecraft. The uncontrolled target RSO’s dynamics are formulated in different operation scenarios, assuming it as a rigid body, with a particular focus on the spinning and tumbling cases. The desired values of the joint angles are obtained to enable the two end-effectors to reach specific feature points on the target in each scenario, facilitating safe and precise physical contact with the target at those designated points. A Lyapunov-based stability analysis of the closed loop system is conducted and stability conditions are provided. Numerical simulations are conducted to validate this work and assess the potential application of dual-robotic manipulators in servicing space vehicles for the removal of uncontrolled RSOs. This methodology presents a promising technique that can be used for RSOs capture and deorbiting in future space missions.