Self‐optimization adaptive velocity control of asymmetric hydraulic actuator

For the velocity control of an asymmetric hydraulic actuator the servovalve is not operated in the vicinity of zero. Thus the linearized model is not easily defined and the classical controller cannot be readily found. Also, because of its asymmetry, a fixed reference model of adaptive control cannot result in optimal performances for both directions. In this paper, to minimize the performance index associated with the estimated model and control penalty, the self‐optimization α‐adaptive control shows an ability to adapt to variations in directions and operating conditions. Thus it will provide similarly optimal performances for both extending and retracting processes. Then, comparing with the variable gain control, the experimental results clearly show its superior performance and disturbance rejection.