Adaptive control for motion synchronization of HA/EHA system by using modified MIT rule

This paper presents a model reference adaptive control for dissimilar dual redundant actuation system that is a combination of hydraulic and electro-hydrostatic actuator. A modified form of MIT rule, called the normalized MIT rule, has been given to find the controller parameters. The reference model is designed on the base of dynamics characteristics of HA. Normalized MIT rule updates the parameter of the controller in such a way that the both actuators follow reference model to reduce force fighting. To assist the model reference controller to improve synchronization and rejection performance, a PID control is used that take into account inherent coupling effect. The proposed strategy not only remove initial force fighting, but also improve load rejection performance of the actuation system.