Design of a linear-rotary micro-stage

This paper presents a linear-rotary micro-stage that can generate motions along and about the Z-axis using piezoelectric elements (PZTs). The small stroke of a PZT is extended by repeating the PZT motions based on a mechanism of impact friction drive. The friction drive mechanism has a simple driving unit, which only consists of a PZT element and a friction element. The moving element of the stage, which is a steel cylinder, is supported and actuated by a driving unit, which consists of two PZTs and a friction component made by permanent magnet. The magnetic force is employed for holding the moving element and stabilizing the driving condition. The dimension of the stage is 7.0 mm x 8.8 mm x 7.5 mm. The moving ranges of the stage are about 5.0 mm in the Z-direction and 360 degrees in the theta(z)-direction, respectively. The maximum moving speeds are approximately 30 mm/s and 84 rpm in the two directions, respectively.