Alternative Energy Project

Our Task

One week ago, we where tasked with creating some sort of vehicle that could move as close and stop as 5 meters as possible. Our group had a few ideas at the start but the one that we decided to go with was tying 2 rubber bands together, tying one end of the rubber band to the front of the car, and the other end on the axle of the back wheels. This way as you pulled back the car on the ground, the rubberbands would rap up causing a lot of tension, and when released, the rubber bands would pull the axle moving the car.

Our Process

We didn't know where to start after having this idea, so we first thought that we needed a blueprint, so we made a blueprint but scaled up so we could see all the parts that where needed to make the car. After this, we grabbed supplies and pieces that where need for the car, so we started out with a light weight chassis which was made out of a piece of wood that was about 3"x 8". After this we decided to drill out holes on both ends for the axle. We had the front end lower than the rear because of the axle the little tires had. The little tires had a metal axle which minimized friction rather that the bigger axle that was a wooded rod that was connected to CD's. Once we had th e general part of the car done, we needed to implement our idea of the "Alternative Energy" part of the vehicle, so we needed rubber bands, and a whole lot of them since they broke so easily. You first needed to tie two together, with one end tied to the front of the car where there were two nails on either side. Which meant that there were twice the rubber bands which led to a greater potential energy, which led to a greater kinetic energy, which then led to thermal energy. Once you had both pairs of rubber bands tied up, all that was needed to do was pull that car back and release, and the rubber bands would do the rest for us.

Modifications

After a couple test runs, there where already multiple problems that where getting in the way from our car even getting close to 5 meters. The first modification we made was applying a rubber band on to the outside of the disc, and we did this to maximize the friction with the wheels on the ground, since when we released our car, the wheels would spin out, resulting in us loosing a lot of valuable energy. The second modification we made was to re drill new holes for the axles, because the axle wasn't siting straight, resulting of not all four wheels being on the ground at the same. This led to the car veering off to one way instead of going straight. Another modification we made was to make the rubberbands longer, so that we could wrap it more times resulting inmore potential energy without the rubberbands breaking as often. This led to more distance with less snapping of the rubber bands. One more modification we made was adding spacers onto the axle to stop the chassis from moving every where. This limited the amount of play there was betwean the frame to the axles, which made it more stable. We also ran the car after these modifications and collected data on the speed, distance, and time where we made some graphs from this data.

Content

- Spring Potential Energy

Spring potential energy is the energy stored in the stretch of an object. Our vehicle had a Spring PE of 1.59 Joules.

- Gravitational Potential Energy

Gravitational potential energy is the energy an object has due to its height or position in a gravitational field. Our Alternative energy vehicle had PEg of 0.273 Joules.

- Kinetic Energy

Kinetic energy is the energy due to motion. Our vehicle had a KE of 0.343 Joules.

- Total Energy

Total energy is the overall energy of the object. Our vehicle had a total energy of 2.33 Joules.

- Thermal Energy

Thermal energy is the energy lost to heat. Our vehicles peak thermal energy was 2.33 Joules.

-Rotational inertia

Rotational inertia is how an object that is rotating stays rotating. Rotational inertia can be found in the wheels of our car.

Reflection

Overall, I thought me and my group had an excellent final product and an even better journey through it. Not only did I learn new material, but I got to learn a little bit more about the people in my group. Two things I thought I did well was leadership, as keeping everyone on task wasn't the easiest thing to do, but at the end of the day, I got it done. And I think thats where a huge piece of the productivity in these projects come from, and thats staying on task. Another thing I thought I did well in was being encouraging and helpful, and its always good to bring people up that bring them down, and I also thought that my group worked better knowing that everyone had an even load of work, so that one person wasn't doing to much or to little. Two things I can work on is helping others, if thats just helping them if there stuck on a problem in class, or outside of class. I think thats one skill that I need to work on. Another thing I could have done better on was listening to others and the ideas they had because you never know if what they have to say, is just the thing your trying to figure out. All in all, I though we did a very good job and had a blast all the way through from the image in our heads to the last modifications to make it run as smooth ass possible. I am so excited to start the next project and the many more that come.