New practical control of point-to-point positioning systems: Robustness evaluation

This paper presents robustness evaluation of the new practical control method for point-to-point (PTP) positioning systems. The proposed controller consists of a nominal characteristic trajectory element and PI elements. The trajectory element is determined experimentally based on open-loop step responses of the position and velocity of the plant. So it includes the non-linearity effects of the plant such as friction and saturation. The trajectory is also used to determine the PI coefficients. Therefore the proposed controller does not required an exact model and parameters of the plant. It is proved experimentally that the proposed controller is better than the conventional PID ones in robustness to parameter variation.