Hybrid Controller using Fuzzy SMC and FOPID for 3-DOF Robotic Manipulator

This paper presents a hybrid control strategy, Fuzzy Sliding Mode Controller, combined with Fractional Order Proportional Integral Derivative for a 3-DOF robotic manipulator. The proposed hybrid controller inherits robustness from Fuzzy Sliding Mode Control against external disturbances and the improved transient behavior and steady-state error of Fractional Order Proportional Integral Derivative. In this work, the gain that pushes the states toward the sliding surface in the Sliding Mode Controller is tuned using deep reinforcement learning and then expanded upon using fuzzy logic. Fuzzy Sliding Mode Control configuration is known to be robust against parameter uncertainty, load disturbances, and non-linearities. The performance of the proposed scheme is tested by applying two different disturbance scenarios to the system. The simulation results show that the hybrid fuzzy sliding mode controller with a fractional order proportional integral derivative controller outperforms the traditional proportional integral derivative controller regarding trajectory tracking in both ideal and non-ideal cases.