Linearized Virtual Energy Tank for Passivity-Based Bilateral Teleoperation Using Linear MPC

Abstract

Bilateral teleoperation systems are often used in safety–critical scenarios where human operators may interact with the environment remotely, as in robotic-assisted surgery or nuclear plant maintenance. Teleoperation's stability and transparency are the two most important properties to be satisfied, but they cannot be optimized independently since they are in contrast. This article presents a passive linear MPC control scheme to implement bilateral teleoperation that optimizes the tradeoff between stability and transparency (a.k.a. performance). First, we introduce a linear virtual energy tank with a novel energy-sharing policy, allowing us to define a passive linear model predictive control (MPC). Second, we provide conditions to guarantee the stability of the nonlinear closed-loop system. We validate the proposed approach in a teleoperation scheme using two 7-degree of freedom manipulators while performing an assembly task. This novel passivity-based bilateral teleoperation using linear MPC and linearized energy tank reduces the computational effort of existing passive nonlinear MPC controllers.