Quasi-Synchronization Control of Multiple Electrohydraulic Actuators With Load Disturbance and Uncertain Parameters

Abstract

This article discusses the quasi-synchronous tracking control of multiple electrohydraulic actuators (MEHAs) with load disturbances, and parametric uncertainties. Each electrohydraulic actuator (EHA) has a third-order nonlinear dynamics in the presence of unknown lumped uncertainties resulting from some uncertain hydraulic parameters, and external load. First, the isomorphic MEHA system is constructed, which extracts the nominal model from the lumped uncertainties. Then, an adaptive quasi-synchronization controller is designed such that each cylinder position of the MEHA system tracks the desired trajectory in a collaborative manner. To compensate the lumped uncertainties of the MEHA system, adaptive laws are constructed, and the resultant quasi-synchronization controller guarantees that all the closed-loop signals, and the estimate errors are uniformly ultimately bounded. Finally, the effectiveness of the proposed control method is verified by simulation, and experimental results.