On Passive Velocity Field Control of Robot Arms

In the passive velocity field control the interaction between a robot arm and its physical environment is passive. If physical interaction is not presented the mechanical system moves along the integral curves of a desired velocity field with speed proportional to the initial stored energy of the robot. Motivated by Lyapunov´s direct method, this paper extends the results in (Li and Horowitz, 1999) by presenting a class of controllers which solves the passive velocity field control objective. An important characteristic of the proposed approach is the shaping of the total kinetic and potential energy of the closed-loop system dynamics. Besides, the problem of pure velocity field control is also considered, which consists in the following of the integral curves of a desired velocity field with speed proportional to a user-defined constant