Naturally-transitioning Rate-to-force Control

The Naturally-Transitioning Rate-to-Force Controller (NTRFC) for manipulators is presented. In free motion rate control is provided, while in contact the same rate commands are proportional to the force exerted on the environment by the manipulator. The transition between free motion and stable contact with the environment requires no changes in control mode or gains and hence is termed natural. The NTRFC has been experimentally implemented and shows great promise. This paper demonstrates the NTRFC concept and provides a basis for its modeling and design.