Robust nonlinear PID-like fuzzy logic control of a planar parallel (2PRP-PPR) manipulator

- A comprehensive analysis of a planar parallel robot (2-PRP and 1-PPR) is presented.
- A robust nonlinear PID-like fuzzy tracking controller with disturbance compensation has been proposed.
- Applicability of the proposed controller has been demonstrated with prototype experiments.
- The robustness of the proposed controller is evaluated over existing controllers.

In this paper, a robust nonlinear proportional-integral-derivative (PID)-like fuzzy control scheme is presented and applied to complex trajectory tracking control of a 2PRP-PPR (P-prismatic, R-revolute) planar parallel manipulator (motion platform) with three degrees-of-freedom (DOF) in the presence of parameter uncertainties and external disturbances. The proposed control law consists of mainly two parts: first part uses a feed forward term to enhance the control activity and estimated perturbed term to compensate for the unknown effects namely external disturbances and unmodeled dynamics, and the second part uses a PID-like fuzzy logic control as a feedback portion to enhance the overall closed-loop stability of the system. Experimental results are presented to show the effectiveness of the proposed control scheme.