Feedforward reference compensation using bilinear interpolation for long range motion of six degrees-of-freedom magnetic levitation planar motor

Magnetic levitation planar motor was researched and developed for vacuum compatibility. Laser interferometers are used in order for high precision measurement. However, the magnetic levitations cannot experience full working range due to the high sensitivity of the laser interferometers. Especially, angular alignment is important for laser interferometer to measure the motions. In this paper, a cause of the lower angular alignment along the long range motion is investigated and feedforward reference compensation using bilinear interpolation is utilized to improve the angular alignment. In order for verifying the compensation, experimental work was performed and the result showed that the angular alignment was improved. Finally, the magnetic levitation planar motor can have full working range motions including 2-dimensional motions by suggested compensation.