Intelligent control of a direct-drive robot using multi-stage fuzzy logic

A multi-stage Fuzzy Logic Controller (FLC) is developed for a 2-link, direct-drive robot. The multi-stage controller intelligently blends proportional-plus-derivative control with integral control for rapid response and zero steady-state error. The robot model includes a computed-torque control scheme based on ideal robot parameters. The multi-stage controller provides superior tracking over conventional PID control with and without plant parameter variations.