Extremum Seeking Based on Sliding Mode Control for Precision Motion Systems

This paper investigates the implementation of ultraprecision control in industrial settings, with a particular emphasis on overcoming the waterbed effect in linear controllers, mitigating the chattering phenomenon in sliding mode control, and optimizing feedback controller parameters. A hybrid control strategy is developed, combining linear and nonlinear control techniques, effectively resolving the waterbed effect and chattering issues. The strategy includes the innovative use of Second-Order Integral Sliding Mode Control (ISMC) within a nonlinear feedback channel. Additionally, a self-tuning method employing discrete extremum seeking is introduced to dynamically optimize the controller’s gain, enhancing system responsiveness and stability under various operational conditions. The paper details model development, outlines the control methodology, and presents simulation results, demonstrating the efficacy of the approach in tackling these challenges.