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source: https://www.simplyrecipes.com/recipes/how_to_chop_an_onion/
To accomplish this goal, our prototype would need to alternate between two functions:
- cut the onion
- move the cutting mechanism to the next cutting angle
With this in mind, we devised the design concept seen in the image below.
This idea hinges on a gearbox (highlighted in yellow) that alternates between two outputs that each complete one rotation before switching to the other. In this way the top output would operate the knife while the bottom would turn a worm gear that would index to the next position.