Trend of Precision Positioning Technology

This paper describes recent precision positioning technology. First, recent precision positioning mechanisms are introduced. Although ball screw mechanisms are widely used in industrial machines, the use of linear motors and the development of planar motors recently increase. Several linear motor mechanisms show the acceleration higher than 10G. The linear motor mechanism developed in my group can move at the higher acceleration than 101G. Next the control methods for precision systems are explained. In many precision positioning systems, it is very important to overcome friction problems. For conventional positioning systems with friction, a practical control named NCTF(nominal characteristic trajectory following) control is introduced. Finally, the self-alignment method using liquid surface tension is introduced as a simple and practical method for self-assembly of microparts..