Dexterous robotic manipulation via a dynamic sliding mode force/position control with bounded inputs

Grasping and manipulation are common robotic tasks which require to properly control the interaction forces and position of multiple robots end-effectors. In this study, the authors focus on the problem of dexterous manipulation of rigid objects by means of a cooperative robotic system. Unlike several works, they consider the more complex case when the manipulated object is not mechanically attached to the robots' end-effectors. In addition, they address the control problem of designing a control law with continuous and bounded input torques for cooperative robots in constrained motion. To guarantee a stable grasp and a fine manipulation a centralised control algorithm based on the Orthogonalisation principle and a dynamic sliding mode control is proposed. The control algorithm does not require the knowledge of the dynamic model of the robot manipulators and manipulated object for implementation. Experimental results are presented to show the good performance of the proposed controller. In addition, the stability analysis of the closed-loop dynamics is developed.