Auburn, MA. Precision motion and nanopositioning company PI (Physik Instrumente) announced it is delivering a family of compact linear and rotary stages driven by ceramic direct-drive motors. The patented ultrasonic motors provide smooth motion with high resolution and a high dynamic range. The self-clamping motor principle locks the stage into place, devoid of creep, once a target position has been reached. This intrinsic brake-like behavior comes at no extra cost, and provides advantages that are not available with classical electro-magnetic drive technologies.
Two linear stages with 18-mm and 22-mm travel are available, as well as an XY stage providing 22×22 mm. Several encoder options, from 0.4 µm to 10 nm, are standard. All stages achieve closed-loop peak velocities to 200 mm/s. The rotary stages come with turntable diameters from 20 to 50 mm, encoder resolution down to 17 µrad, and maximum velocity of 720°/s.
The low inertia direct drive (no gears and other mechanical components to convert motion) allows for a very dynamic start-stop behavior with settling times in the millisecond range. Based on the ultrasonic principle with drive frequencies >100 kHz, the motors are silent. Displacement is generated in continuous sub-nanometric increments, leading to extremely smooth motion with a wide dynamic range.
Linear and rotary stages can be combined to form multi-axis combinations. Due to the high efficiency of the ultrasonic motors, the miniature stages can be integrated into mobile measuring and medical devices. Vacuum compatible versions are also available.
http://www.pi-usa.us/products/Compact_Positioning_Stages/#Ultrasonic