A fuzzy Lyapunov-based control strategy for a macro-micro manipulator: Experimental results

A class of model-free fuzzy controllers based on the Lyapunov-function reasoning is presented for a Macro-Micro Manipulator (M3) system. The control strategy uses the structural properties of the system model and assumes no other a priori knowledge about the system dynamics. Although, in general, the control structure can be regarded as a fuzzy controller, it may also be interpreted as a nonlinear multi-input multi-output (MIMO) proportional-integral-differential (PID) controller. An experimental setup consisting of a three-link M3 is considered as a practical case study. The test-bed is a nonlinear nonminimum phase MIMO system with a complex model and considerable joint frictions. Experimental results are presented to illustrate the improved performance of the proposed control strategy over a joint PD controller.