A new method using pole placement technique to tune multi-axis PID parameter for matched servo dynamics

Abstract

A new method which employs pole placement technique of modern control theory to tune proportional–integral–derivative parameter for simultaneously achieving multi-axis matched dynamics and single axis stability is addressed in this article. This method has the advantage of simplicity in tuning, intuition in principle, and easy in program. Four different cascade proportional–integral–derivative control structures are investigated for applying the matching method appropriately and better understanding of its limitation. The deduction that the feedback gain ratios of position to speed loop of the same type interpolation axes imposed with the same desired poles are approximately equal is obtained. Experimental results show that the servo feed system designed or tuned by the proposed method can easily achieve matched dynamics. Furthermore, this method can be also employed to multi-axis motion system which is composed with both linear and rotating axes.