Piezoelectric Stage for nanometer level precision

mawyatt2002 wrote:

ProfHankD wrote:

mawyatt2002 wrote:

Awhile back the surplus market made some Physik Instrumente piezoelectric devices available. The devices offer the potential for extreme resolution and high precision when operated "Closed Loop" with position feedback. The complete OEM Closed Loop controllers/drivers/amps are very expensive, so an effort began to develop a custom solution at a much lower cost. One solution is a full Custom Complete Closed Loop system adaptable to various piezoelectric stages (P601K, P603K for example), another was a Custom Controller to interface with the OEM P603K Driver/Amp which are available on eBay at reasonable costs. Both operate from a Raspberry Pi with a single +12V at <1/2 amp supply.

Pretty slick....

If I were doing this, I think I'd just wildly gear-down a stepper... perhaps to drive a movement extracted from a cheap micrometer (e.g., like this ). Less driver circuitry needed, but a bunch of 3D-printed parts for mounting.

Thanks,

Gears have all sorts of issues with backlash, moving surfaces, mechanical noise and so on, and suspect even quality micrometers can't achieve these levels.

The piezo ceramic elements expand or contract at the molecular level based upon electric field, so there is no mechanical surface to surface movement. The cleverly engineered "flexures" in the Piezo Stages are like bending gears without any noise, hysteresis or other effects that plaque conventional bearings, however they have limited movement range. The piezo elements are held in position at the ends by natural compression and don't move during general excitation. So in normal operation these Piezo Stages have no surface to surface mechanical movement.

I'm familiar with piezo motors/actuators. They're actually commonly used in lens focus systems. There are lots of different types of linear actuators out there. All good stuff.  I just think they're a bit beyond the usual do-it-yourselfer level....