Now this is a build I was looking more for in a jointer for your table saw.  The arduino with a stepper is used to move the wood into each position to make the next joint.  I like the hold downs for the wood to “joint” the author added on to it.  My 2 cents, I would have moved the control box so it was attached to the unit as well.  And instead of putting this on a sled of its own, maybe made it to attached to a sled.
https://www.instructables.com/id/Arduino-Controlled-Finger-Jonter/