General Discussion: Mouse Trap Car Pulling Mass

[Facerollmage]

If you were limited to only using a single mouse trap and cheap raw materials from a local craft store, how would you design a "mouse trap car" to pull a mass of 200g (soda can w/mass)?

I'm looking to maximize the mouse traps distance traveled and speed.
I'm looking to minimize the weight of the total system.

I was thinking of a 2 axle setup with larger wheels in the front and smaller in the back to prevent lift when it accelerates. For the motion mechanism I am leaning towards a "yo-yo" effect on the wheels that when the trap goes off, a string that is tied to the metal clamp on the trap unravels the string tied around the wheels.

I'm currently testing new ideas and trying to optimize as much as possible.

How would you design a mouse trap car to achieve the previous stated goals or how would you better the design that I am leaning towards?

 

[braren]

This sounds like a fun project. I'm assuming some sort of college intro to eng. project?

I'd probably go with a long body so wheel alignment isn't quite so critical, that way the car will be less likely to turn. I think the yo yo type of mechanism is also good, that's how most (if not all) people will probably do it. There are other ways to do it, but I think they would be not worth the effort. I think in this project, the things that will make one car stand out over the other is not going to be how the potential energy from the spring is converted to rotational energy, but rather, how well other parts of the car are designed (low weight, drives straight, low friction in axle bearings, etc). Although there is one exception I possibly see. Are you allowed to disassemble the mouse trap? If you are, then you should make sure to do that so you can bend the spring farther back and get more energy out of it.

 

[braren]

Also, I'd use as inelastic of a string as possible, maybe even some sort of wire, because you don't want to lose energy by stretching the string (even if only by a little)