Alternative Energy Vehicle

The Task

The task given to us was to make a vehicle powered by an energy source other than chemical or nuclear. The vehicle must be able to transport two passengers (rolls of pennies) as close as possible to five meters and as fast as possible. We then gathered the data from our tests and graphed the performance of our vehicle.

Our Slideshow Presentation

The Process

This project was in two parts. The first part of our project was to build a catapult/ trebuchet that was supposed to fire a projectile as far as it could within a few regulations. Some of the regulations included that it could not exceed over a meter, must be reusable, must have a base, portable by one person, and should be able to fire by itself. Our catapult was not very successful in the beginning and would either not shoot or travel very little distance. Then we made eight different modifications to the catapult and it worked a lot better and was probably one of the better preforming machines in the class.

The second part of the project was the alternative energy vehicle. We stayed in the same groups for this project because the catapult and trebuchet unit did not last long and we were nearing the end of the semester. I was happy with staying in our same group because I think we work very well together and we all have a different way of thinking so there were many different ideas. In the beginning of our project we did not have a very clear idea on the energy source we were planning to do so we thought of it as we were building our vehicle. One modifications we made to our vehicle was that at first we glued the axle to the base of the car and only the wheels were going to move. We then noticed that this was not going to work very well so we glued two PVC pipes onto the base and put the axle and wheels together so they could rotate as one. The we we made our vehicle work was using a different piece of wood with a screw on the end sticking up where you can attach a rubber band between the piece of wood and the car and use it as a slingshot. The rest of the project after the completion of our car consisted of us taking data from our test runs, plotting the data onto graphs, and making our presentation.

Content

Spring Potential Energy (PEspring)- Energy stored in an object due to expansion or compression. Spring potential energy is equal to one half K times x squared. K being the spring constant. Unit or spring potential energy is joules.

Gravitational Potential Energy (PEg)- Energy an object has due to its position at a height or in a gravitational field. Potential energy equals mass multiplied acceleration due to gravity multiplied by height. Unit of potential energy are joules.

Kinetic Energy (KE)- Energy due to motion. Kinetic energy is equal to one half mass multiplied by velocity squared. Unit of Kinetic energy are joules.

Total Energy- The total Amount of energy within the object. The way to calculate total energy is to add all of the energies of the object. Unit of total energy is joules.

Thermal Energy (TE)- Energy lost to heat or transferred. Thermal energy is total energy subtracted by potential energy and kinetic energy. Unit for thermal energy is joules.

Distance vs. Time- The ratio of the of how long it took the car to go each meter. How many seconds it took from the car to go from meter to meter.

Velocity vs. Time- The velocity our car has when it is traveling on the ground. (m/s)

Rotational Inertia- The mass distribution from the center of an object. More outside mass means more rotational inertia and harder to get going. More inside mass means less rotational inertia and easier to get going.

Reflection

These two projects have been some of my favorites we have done so far. I was really looking forward to these designing and modifying these two machines because I have always been interested in the things we learned in this unit. The first question Mr. Williams asked us going into these projects were trivia questions about cars so I figured that these projects were going to be right up my alley.

I really enjoyed the process of this project. I enjoy making building different things other than some of the other projects we have done earlier in the year. I enjoyed these two projects and the Rube Goldberg machine project more because of this reason. For example with the catapult we thought that with our first design ours was going to be one of the best out of the whole class but turned out to be the worst. We then made eight adjustments to the catapult like changing the effort to load ratio and changing the axle height. We also made a couple adjustments to our car too. I our first prototype we had six wheels but we decided to change that because the extra two wheels were just adding friction to our car. Another modification we made was changing the wheel and axle. The modifications from both machines increased there ability greatly.

Overall I really enjoyed this project. I think that our group changed a lot during this project and we got a lot better at working together and as a team. We may have had some ups and downs but we worked them out and did not them them slow us down. I really enjoyed doing this project because it was very hands on and I got to learn about many thing that interest me and some things that I learned may help me in future jobs I may apply to.