Haptic knob
Video editors appreciate an intuitive interface with which they can readily and intuitively perform functions such as fast forward, rewind, frame stepping, etc.
A client who supplies video editing consoles had the idea to replace four passive mechanical knobs with knobs connected to motors and a microcontroller. This facilitated different video editing tasks. For example, a knob could be programmed to emulate the feeling of a spring return to center when fast forwarding or rewinding and then be converted to a 30 detent knob for frame by frame stepping.
A fun part of this project was using the graphical interface which made it easy to draw a curve of how the knob should feel and then trying it out on the knob.