Application of a digital signal processor in compliant Cartesian control of an industrial manipulator

This paper presents an example of compliant manipulator control implemented on a DSP chip. Drake and Hsia (1993) discussed the algorithms for computing the manipulator forward and inverse kinematics, Jacobian, J(θ), J^-1, J˙θ˙, and Newton-Euler inverse dynamics. These algorithms were unified under a common coordinate system and optimized. Here, these tools have been augmented by a six D.O.F Cartesian trajectory generator, and a Cartesian impedance control scheme. The algorithms are implemented on a TI TMS320C30 DSP chip. In the approach presented here, direct Cartesian control is used, so that inverse kinematics computations are unnecessary, and a simplified dynamic cancellation scheme is used. This controller has been successfully tested on a PUMA 560 manipulator with a PC-based controller. This paper presents an overview of the previous work, a discussion of the trajectory generator and the impedance controller, and experimental results. In addition, the timing of the individual routines is presented.