Adaptive prescribed control of position and attitude of combined spacecraft based on fully actuated system approach

An adaptive prescribed performance controller based on the fully actuated system approach is designed for the position and attitude control of the combined spacecraft formed after the successful capture of the non-cooperative spacecraft, considering the influence of unknown disturbance in the combined spacecraft system. A combined spacecraft position and attitude dynamics equation is established based on the Euler's attitude dynamics equation and the orbit dynamics model. The transient and steady-state performance of the combined spacecraft position and attitude error is constrained by introducing a prescribed performance function. Furthermore, the adaptive prescribed performance controller is designed for the combined spacecraft state error system with unknown disturbance by applying the fully actuated system approach. In addition, the proposed adaptive prescribed performance controller is proved by constructing the Lyapunov function. Finally, the numerical simulation results based on the combined spacecraft system model and the experimental results obtained from the semi-physical simulation platform show that under the action of the designed controller, the combined spacecraft can achieve accurate position and attitude control and the state error of the system is always within the prescribed performance envelope, which verifies the effectiveness and practicality of the designed controller.