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Piezo actuators challenge leadscrews

20 January, 2009

The piezo motion specialist Physik Instrumente (PI) has developed a range of ceramic linear motor actuators that challenge conventional leadscrew actuators. In contrast to DC servo or stepper motor actuators, PI claims that the new devices offer almost unlimited travel ranges, millisecond response rates and speeds of up to 10mm/s.

The tiny N-380/N-381 Nexact actuators combine high forces (1kg push/pull) and long travel ranges (30mm) with sub-nanometer resolution.
 
The lubricant- and wear-free actuators use a “piezo walk” drive system in which piezoceramic bending elements act on a ceramic runner connected to the moving tip. This produces linear motion directly, without needing to transform rotation using gears or leadscrews. Backlash and wear are eliminated and the drive is maintenance-free.

The actuators exhibit high stiffness and are self-locking when powered down. For long movements, a stepping mode is used; for shorter distances and highly dynamic motion, an analogue (sweep) mode can be used. The 40V actuators can be controlled via USB or RS-232 links or by joysticks.