For the final project, I mashed together a few of the ideas I had been exploring. Both the a wall-mounted kinetic sculpture with linear motion and the scissor mechanisms made their way into this piece.
A rack and pinion are driven by a stepper motor controlled by an Arduino micro-controller. The linear movement of the rack is translated into rotational movement around fixed points at the ends of connected arms.
As the rack and pinion move up and down the scissors open and close, creating interesting geometric formation. If I were to move forward with this idea, I’d develop a more elaborate system of scissor arms so that the translation of the linear movement creates wildly expanding and contracting motion in the arms.
Next up was a gear-driven scissor lift. I prototyped with Acrylic and Delrin.
Turns out that the material properties of the Delrin aren’t ideal for laser cutting. There was a little meltiness and a lot of unevenness along the cuts. This created a lot of friction and twisting along the vertical axis when the lift was constructed. I even added springs to assist with closing but the friction was too high for them to make any difference.
My proposal was for a kinetic sculpture/s that were driven from a single point. Each would be a basic shape with a track hidden on the rear. A wall-mounted motor would drive the shape along the track without rotating it.
The idea started with the square. But it turns out that that’s a difficult problem. So I broke it down into trying to just drive a square piece along a square track.
Also a difficult problem.
While prototyping I figured that a rod fixed at one end, rotating at the same rate as the small square in the track would (depending on the length of the drive-arm) describe a clover-like shape.
After talking to some more mathematically inclined friends I got my hands on a processing sketch that helped describe the shape. As the rod rotates, the small ellipse will draw the clover onto the moving square.
This is that shape.
I wasn’t able to determine an exact equation for the measurements of the shape, so I guesstimated how far the free end of the drive needs to move. That gave me enough movement to test. But it became very clear very quickly that the measurements of all of the pieces needed to be way more exact than I was able to cut for this to work.