Build a better mousetrap, Ralph Waldo Emerson once said, and the world will beat a path to your door. Build a better mousetrap car, Taft engineering teacher Dan Calore says, and the world of engineering becomes your oyster.
Students in Calore's Introduction to Engineering class recently built and raced model cars driven by the same force that causes a mousetrap to snap. Attaching a string to the lever arm then wrapping it around the drive axle creates tension in the mousetrap spring. Once the lever is released, the tension pulls the spring over the drive axle and the wheels begin to rotate, setting the vehicle in motion.
"We gave each student a kit so that they were all starting with the same standard parts," Calore explains. "But we threw the kit directions away. Part of the engineering process is to develop an understanding of the mechanics of how things work, and to then apply that understanding to solve problems."
After the initial build component, students were asked to modify their designs to improve vehicle performance on two measures: total distance traveled, and velocity over a three-meter course.
"Modifying the vehicles forced the students to think about some of the basic principles of engineering," says Calore, "energy, forces, and motion. They needed to ask themselves, what factors impact speed? What factors influence distance? Most figured out that the rear wheels needed friction and created that by adding rubber balloons to wheel edges. Others developed a kind of gear transmission, or adapted different size wheels for speed and distance."
With each modification, students were asked to assess whether the change made performance better or worse, which, notes Calore, is a very important part of the process.
"The biggest thing that I got out of the project was problem solving," says Nick Cutler '17. "In the beginning, we were given our supplies and that is what we were to work with; there were not additional supplies, so if something broke we had to find a different way to make our cars work. On the second day, the foundation of my car broke in half, and I had to completely start over. I had to look around the shop for different things that I could use in place of what I broke; the point was to find a way to get the job done."