Scaling and eliminating non-contact forces and torques to improve bilateral teleoperation

In bilateral teleoperation, the operator experiences forces and torques applied to the slave manipulator. These forces and torques, however, consist of two components: on the one hand, forces and torques due to contacts with the environment, and on the other hand, non-contact forces, i.e., inertial forces, centrifugal forces, Coriolis forces, and associated torques. For several reasons, eliminating these non-contact forces and torques from the force-torque measurements of the slave or scaling them can be advantageous. For instance, in highly-dynamic teleoperation tasks, these forces and torques may contribute to operator fatigue or hamper the detection of contacts with the environment. This paper briefly reviews the estimation of inertial parameters of the slave load, e.g., an end-effector or a gripper. Subsequently, a method for eliminating the non-contact forces and torques from the measurements of a wrist-mounted force-torque sensor or scaling them is presented. After a brief overview of our teleoperation system, experimental results are presented which demonstrate the effectiveness of our approach.