Adaptive prescribed performance control for the post-capture tethered combination via dynamic surface technique

In this paper, an adaptive dynamic surface controller with prescribed performance is proposed for the stabilization control of the post-capture tethered combination, where the factors such as measurement uncertainties, model uncertainties, external disturbances and input saturation are considered. Compared with the most prescribed performance approaches, the proposed controller has a simple structure, and needs no error transformations. Firstly, we found a dynamic model of the post-capture tethered combination considering the integrated attitudes of the combination. Then, taken the above-mentioned factors into consideration, the dynamics of the post-capture combination can be transformed to a multi-input-multi-output (MIMO) system with mismatched and matched uncertainties. An adaptive approach is proposed for estimating the upper bound of the uncertainties. Furthermore, an auxiliary dynamic system is adopted to deal with the problem of control input saturation, and the bounded assumption of input error is released. All the signals in the closed-loop system are confirmed to be ultimately bounded by the Lyapunov stability theory. Finally, simulation results validate the performance and robustness improvement of the proposed control algorithm.