Abstract: For addressing the manipulator base attitude coupling issue of space robots, a model free decoupling approach based on time delay estimation (TDE) is proposed to achieve the coordination control between the manipulator and the base. Firstly, the dynamics of the system is deduced by the composite rigid dynamics modelling approach. Then, by analyzing the dynamic coupling property, the model free decoupling control based on TDE is designed from the multi input multi output (MIMO) viewpoint to realize the high precision tracking control of the manipulator and attitude stability control of the base. Finally, comparing the proposed approach with the classical model based decoupling approach, namely, computed torque control (CTC), by numerical simulation, the results indicate that the TDE control approach is more efficient and has a better decoupling performance.

Key words: Space robots, Manipulator base attitude coupling, Time delay estimation (TDE), Composite rigid dynamics modelling approach, Model free decoupling controller