Active Disturbance Rejection Control for Dielectric Electroactive Polymer Actuator

This paper presents the Active Disturbance Rejection Control (ADRC) designed for a Dielectric Electroactive Polymer (DEAP) actuator. ADRC has gained popularity in recent years as an effective alternative approach to solving control problem in relation to classic PID controller and the model-based approach. It is a valuable control methodology due to its simple tuning method and robustness against process parameter variations. The novelty of this article is a simple control method of DEAP actuator based on ADRC schema. This work presents a method of identifying the parameters of the actuator model necessary to develop the ADRC control. Then Linear Extended State Observer (LESO) was developed which is used for compensating the effects of total disturbance. The linear proportional-derivative (PD) controller, which in ADRC control scheme can be considered as a state feedback controller, has been implemented in the external feedback loop. This approach makes it possible to use the system with a simplified DEAP model, because the negative effects of modeling uncertainty are compensated in real time. The tuning process of ADRC parameters (performed in the terms of LESO and PD controller bandwidth) is discussed and presented graphically. The experiments show the transients of the ADRC control system and the performance indexes of the two reference trajectories in order to verify the effectiveness of the control system.