Teleoperated Single-Master-Multiple-Slave System for Cooperative Manipulations in Task Space*

In this paper, the framework of a single-master-multiple-slave nonlinear manipulator system is proposed for the remote regulation of cooperative tasks. To simultaneously implement both the teleoperation and the cooperation in the presence of time-varying delays, external disturbances and modelling uncertainties, an adaptive non-singular terminal sliding-mode (ANTSM) method is used. Through a wrench-prediction-based reference model, the master controller can be designed as a motion controller while considering the environmental wrench feedback. Additionally, as the full pose motion regulation is considered, an optimized load distribution method is used for the load allocation in 6 degrees of freedom (DOFs) and to compensate for the additional internal torque. Simulation results of a team of 3-DOF Phantom Omni haptic devices show that the designed controllers can ensure that the tracking errors are bounded and the resultant overall multi-manipulator system is stable.