Joint space torque control with task space posture reference for robotic-assisted tele-echography

This paper presents a new control approach for robotic-assisted tele-echography. A computed torque control architecture in the joint space is proposed, allowing to control each joint individually while avoiding the explicit computation of inverse kinematics. Posture errors in the task space are converted into velocity references for joint control. Experiments with a 7-DOF WAM™ manipulator have been carried out, where a human operator tele-controls an ultrasound probe in 6 Cartesian dimensions through a haptic device.