Implementation of 7-DOF External Force/Torque Feedback for Master-slave Surgical Robot System

With the urgent need for the implementation of force/torque feedback function in the master-slave surgical robot system, this paper proposes a set of versatile algorithm methods, including filtering, gravity compensation, and posture transformation, to realize the 7-DOF force/torque feedback by using common force/torque sensors. These algorithms are applied to a built master-slave surgical robot system in order to test the force feedback response delay and accuracy. The experimental results indicate that the force feedback response delay is below 100ms; for the accuracy, the error is less than 0.1N, 3% when the angle between the end of the manipulator and the vertical direction is within 15 degrees, which can ensure a good force feedback experience for the operator. Besides, since the algorithms are integrated into one ROS node, through a small workload of modifying, the software programs can be applied to the systems with different manipulators.