Hyundai asked the Stem program to design a prototype of an alternative energy car. The car has to be able to travel 5 meters with a 250 gram weight.
Project History The first few days during this project we brainstormed some car ideas. The first car we tried didn't work very well because it kept becoming unsecure and breaking. We tried to attach CDs to a wind up propeller that is used on toy planes. It kept becoming unattached so we switched our design. We used rubber band power to make the car go. It worked very well and we found out how much to wind it to make it go 5 meters. We put balloons on the CDs to create friction. It was very simple but worked out very well. We spent around 2 days researching and the next 3 tweaking and building our car. It took us about 2 days to create our power point.
This is a picture of our hybrid car
Concepts Spring Constant - The spring constant is a measure of the elasticity of a material. How far a spring or other elastic material extends or compresses is proportional to how much force is applied in each direction. That proportion is called the spring constant. We used it in our vehicle to figure out how much we should wind up the band to get the most accurate distance. The unit are Newtons per Meter (N/m). Elastic Energy - Energy stored in the stretch or compression of an elastic substance. We found this out at each meter our car went by measuring how many times the band was still wound around the front axle. Measured the same way as all other energy sources (J). Pressure - This is the amount of force exerted on a given area. When we were brainstorming, many of our designs involved pressure, even though the end result didn't. Measured in Newtons per square meter, or, the Pascal (Pa). Power - The rate of which work is exerted. Our car had a decent amount of power; this amount could be doubled, however, if you used the second rubber band. Power is measured in watts (w).
Reflection Me, Ryan, Ely, and Brandon worked very well together. We thought very quickly on what we should do for our project. We tried it out but it didn't work. We had a lot of confidence in our first design which ended up not working but our second design worked out very well. We all collaborated very well and ended up with a very good end product. At first we struggled with who did what because it was hard to all work on the car at once but by the end I feel we all understood how we made the car, the design, the concepts, and the point of this project. I learned a lot from the people in my group and they helped me understand many of the concepts I couldn't grasp but now I can.