Passive tool dynamics rendering for nonlinear bilateral teleoperated manipulators

In a previous paper (see ibid., p. 3278-83), a control law renders a 2n-degree of freedom (DOF) nonlinear teleoperator (consisting of n-DOF master and slave robots) as a n-DOF common passive mechanical tool which has the usual robotic dynamics. In this paper, we develop a control methodology to endow the resulting n-DOF common passive mechanical tool with useful passive tool dynamics which incorporates inertia scaling, guidance/avoidance system while preserving energetic passivity of the closed-loop system. A fictitious energy storage is used to scale the apparent inertia of the teleoperator. The passive velocity field control for a velocity field tracking and artificial potential function are utilized for guidance/avoidance system. Thus, with the control law proposed previously, the control law renders the 2n-DOF teleoperator as a n-DOF common passive mechanical tool which has programmable apparent inertia and moves under the effects of velocity/potential field tailored to task objectives and obstacles in the workspace