Algodoo

Reminds me of the San Francisco cable cars. Imagine if they had lead-screws under the streets propelling those vehicles around the city! Not very practical of course. Interesting concept, though.

A cable makes more sense than a screw acting as a rack since the cable would be in tension whereas the screw thread would have a localized cantilever load. For a vehicle with gearing such as the one in this scene, a rolling clamp with (2) opposed pulleys might work as the vehicle input.

I was thinking that if the vehicle had a variable speed transmission, then it could vary its speed.

The screw acting as a rack? Now there's an interesting thought! I imagine that it would somehow need to be supported along its length to keep it from bowing under compressive load. Also, it would need double the length of the road as it extends.... Wait..... that won't work. Bad idea.

Statement: I imagine that it would somehow need to be supported along its length to keep it from bowing under compressive load.
Response: I agree. It could be supported by a half-pipe cemented to the ground.

S: It would need double the length of the road as it extends.
R: Yes, if you push or pull the screw but not if you rotate the screw. I push and pull the screw in the scene but my intent was to make it look like it's turning.

S: "...but my intent was to make it look like it's turning. "



R: One way to do that is with animation like I did in the scene: Nut And Bolt

Nice Project!