Nonlinear PID control on pattern drawing machine

In this paper, in order to deal with the synchro motion of four cylinders in pattern drawing machine, an electro-hydraulic synchro servo system(EHSS) with four cylinders is developed and its nonlinear dynamic model is presented. Based on the theory of taylor expansion, optimal control and nonlinear disturbance observer designing, a nonlinear PID synchro controller for EHSS with four cylinders is proposed such that tracking and synchronization performance is well addressed. The results on simulation and practical application in pattern drawing machine show that the proposed controller has better tracking and sychronization response than the conventional PID sycnhro controller, and is successful for the EHSS with four cylinders in pattern drawing machine.