'Ultrasonic motor' , School of Engineering, University of Glasgow

[ikemkrueger]

How does it work?

[MrPres88]

@ikemkrueger

Hi, I uploaded this on my old account.

Essentially, it's a motor, that's driven using an ultrasonic energy source, as opposed to your typical electromagnetic motors.

An ultrasonic signal generated using a function generator, and passed through a power amplifier we built. A simple non inverting high voltage amplifier, with push pull high power MOSFETS on it's output, to accommodate the high current drawn by the amplifier's load.

[MrPres88]

This amplified signal drives a two PZT discs, enclosed within a BLT horn. The driving frequency matches the resonant frequency of PZT discs, which enables maximum vibrations of the discs. The horn, which was designed to match resonance as well, amplifies the displacement of these vibrations further.

The tip of the horn was then machined down, about 45 degress, and pressed against a basic rotor structure, which rotates freely using a ball bearing.

[MrPres88]

The horn, which is held in place, on G clamps. vibrates, and intermittently drives the rotor. These vibrations are very small and fast, so the human eye observes a free flowing rotor.

Note, that the PZT discs are very capacitive at resonance, and hiders optimal vibrations. The PZT disc must be modelled, to determine the resonance inductance, that cancels out this capacitance. An inductor was then purchase and driven in parallel with the PZT discs, to allow optimal vibration.

[MrPres88]

Ask if you wan't to know more!

[chrismurray72]

Cool, looks really good