A new position control method for lift motors

This paper proposes a precise position control method for lifting motors through a control system of a sapphire crystal orientation device to meet industrial processing requirements. Both the Bang-Bang control and the proportional derivative negative feedback Proportion Integration Differentiation (PID) control are employed in the variable structure controller. For the nonlinear saturation problem, a trajectory planning technique is also introduced in the design to achieve rapid and precise motor position controlling without overshooting. As a proof-of-concept, the proposed method is tested with a Simulink simulation system.