Fuzzy Logic based adaptive control of robot manipulators driven by BLDC Motors

Abstract

This research focuses on designing a joint space controller for robot manipulators whose joints are driven by brushless DC motors. By appending the actuator dynamics to control synthesis and stability analysis, the sensitivity in the sense of positioning and reliability of the robot manipulators is aimed to increase. Uncertainties in both robot manipulator and actuator dynamics are taken into account to obtain improved tracking performance. To overcome these uncertainties, self-adjusting fuzzy logic networks, that is having adaptively updated centers and widths, are used. The developed adaptive controller structure does not rely on acceleration measurements and incorporates only full state feedback. Via utilizing Lyapunov type stability analysis methods, semi-global uniform ultimate bounded tracking result is ensured. To further verify the applicability of presented controller, comparative tests are performed on a two degree of freedom planar robot manipulator equipped with brushless DC motors and satisfactory tracking performance is demonstrated.