Mousetrap Vehicle

Overview
Mousetrap vehicle is a car that you must design to go forward x amount of meters and come back to its original starting point.You will be allowed two un-modified mousetraps which means that the mousetraps must have all the original parts

How to Make it Work
There are three easy designs to get it to come back
 * 1) one mousetrap on each axle you wind one mousetrap up and as it goes down it winds the other mousetrap up to pull it back