Distributed cooperative control of mechatronic system driving multiple electrohydraulic actuators with uncertain nonlinearity and communication delay

Being different from many centralized mechatronic systems, the distributed transmission mechanism has the significant advantage such that realize cooperative task only based on small amount neighbour nodes with low computational complexity. In this study, a distributed cooperative control is proposed for multiple electrohydraulic system (MEHS) to guarantee the follower electrohydraulic node tracking the leader motion, based on the approach of directed spanning tree. Firstly, the MEHS model is constructed as three-orders isomorphic nonlinear dynamics. Then, a disturbance observer is adopted to estimate uncertain nonlinearities caused by hydraulic parametric uncertainties and unknown external loads in the MEHS. To address unknown communication delays in the network topology of MEHS, a quasi-synchronous controller is designed via Lyapunov–Krasovskii technique to guarantee that the synchronous errors asymptotically converge to a zero neighbourhood. Finally, the effectiveness of the proposed distributed synchronous control is verified by simulation results under uncertain nonlinearities and different communication delays.