Sunday, September 8, 2013
I spent some time trying to determine how each of our designs would work. I found lots of information on the traditional design, such as increasing the length of the lever arm, the wheel radius, and the wheel friction. A good way to secure a longer lever arm to the one already on the mousetrap was using zip ties. These are strong, simple to use and allow for the lever to be replaced. Most of these designs used CD's for wheels which, while being light and having large radii, are flimsy and easily breakable and probably not suitable for a child's toy. They also had rubber bands around the CD's for friction. This seems a simple and effective method which could easily be applied to other wheel designs. I found less information on the pull-back design. It seems that this design has not been widely used for mousetrap cars. I did find a video in which someone took apart a pull-back toy car, revealing the gearing inside. While the system of gears itself did not seem overly complex, it utilized a coil spring, whereas the mousetrap has a torsion spring. We thought of a few ways to attach the torsion spring to a gear, including gluing, welding, and bending the end of the spring around a hole in the gear. We were concerned that the force exerted by the spring would either break the gear or the method used to attach the spring to the gear. This could be detrimental to both the function and the safety of the car. Also, it would be very difficult to find gears that would fit into our Lego design, and both difficult and time consuming to build them ourselves.