Silent Motor Drive

Stepper motors usually make noise, because they step, and the electronics also step. So the point was to make steps without stepping. This means making every movement smooth.

Using microstepping helps a lot, but I went further. I use dither stepping, where microstepping and digital signal processing are combined directly with cybernetics to give smooth silent movement to the motor.

In the beginning I used microstepper controllers, but they have been replaced with H-bridges driving the stepper motors directly. They are controlled by an Atmel microcontroller which in the background runs my interrupt based driver routine. It uses negative positional feedback with smooth bessel filters implemented as coupled differential equations.
It is fast too, and do not use much of the processing power.

Rhytms

My silent motor drive was also used in the electro mechanical rhythm box BlinkWheel by Koka Nikoladze. It was featured on the Discovery Channel.

Any comment?
kim.oyhus@gmail.com