I took a class called Robot Mechanism Design which had a large emphasis on actuating complex motions with as few motors as possible. My team decided to build an automated vegetable chopper, using a single motor to both index the vegetables forwards and slice them. The cutting profile was modeled after a video of Chef Gordon Ramsey cutting carrots.
There were also some interesting design and fabrication challenges along the way. To bring the knife from real life to computer design, I ended up taking a picture of it next to a ruler and importing the image to CAD for an accurate profile at the right scale. For the indexing barrel, we used a cubic spline with 80% dwell so that it didn't interfere with the cutting cycle. Our team member is an expert machinist and made this timelapse of this part's fabrication.
Videos of the mechanism in action as well as more in-depth design notes and analysis can be found on the course website.