A linear-rotary stage for precision positioning

This paper presents a linear-rotary (Z–θZ) stage that can generate motions along and about the Z-axis based on friction drive. The moving element, which is a steel cylinder, is supported and actuated by two driving units, each consisting 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 moving ranges and maximum speeds of the stage are 12 mm, 16 mm/s in the Z-direction and 360°, 10.5 rpm in the θZ-direction, respectively. A Z–θZ sensor is also constructed for servo control of the stage.