mouse trap car problem.

i need an idea for a mouse trap that can fit all of this criteria. many thanks Procedure

Competition Categories - In order of running

=B7 Speed: The fastest car over a 6' measured course.

=B7 Strength: The car that can pull the most weight. A sled will be attached to the back of the car and loaded with successive amounts of weights until no car can pull it.

=B7 Accuracy: You must design your car to travel 12', no more

- no less.

=B7 You are allowed to have 2 sets of wheels if you desire. You may change wheels one time during the competition.

Guidelines for Construction

=B7 The mousetrap mechanism can't be altered or modified. However, the base of the mousetrap may be drilled, cut, glued, nailed, or screwed.

=B7 Only the mousetrap may be used to power the vehicle.

=B7 You may not use rubber bands or anything elastic to attach from the mousetrap to the axles of your vehicle.

=B7 Either axle, or both, may be used as the drive axle(s).

=B7 The entire vehicle must start behind the designated START line. All cars will start from the same point, however, they do not have to start in the same orientation they may start angled with respect to the START line.

wrote: i need an idea for a mouse trap that can fit all of this criteria: · Speed: The fastest car over a 6' measured course. · Strength: The car that can pull the most weight. A sled will be attached to the back of the car and loaded with successive amounts of weights until no car can pull it. · Accuracy: You must design your car to travel 12', no more - no less. · You are allowed to have 2 sets of wheels if you desire. You may change wheels one time during the competition.

This is a really really common high school science project. There should be a whole lot of material on the web already.

That said, you need to find out how they're weighting the various factors, since optimization for one will hurt you on the others (e.g. the faster you can do the speed course, the worse you'll do on strength).

A major problem with these devices that I've seen is traction...they're way too light for the amount of torque the mousetrap can delivery so they spin their wheels.

Accuracy is easy if you don't have wheel slippage...simple kinematic analysis of your drivetrain will let you set that right. Speed and strength are tradeoffs, so you need to know how they're grading each one. Since they let you trade wheels once, I'd have speed wheels for the first run then switch to strength wheels for the strength/accuracy segment. That's basically just changing your gear ratio. If you change the wheel material at the same time, you can use that to adjust your vehicle weight/traction.

Tom.