Alternative Energy Vehicle

To start off, the project was to transport two rolls of pennies as close to five meters as we could safely using a non-chemical energy source. We started by brainstorming possible methods of transferring energy to our vehicle as well as sketching out a design for our vehicle. After some brainstorming, we decided we could utilize hydraulics, rubber band spring potential energy, or a large arm to hit our vehicle. After a little more discussing, we decided that hydraulics we be too difficult to build as well as too difficult to calculate the physics of, and then we noticed that mostly everyone else was using the same rubber band technique, so we decided to use a large arm. And thus began the final stages of blueprinting, giving us our baseline design for us to build and then test.

We split the workload of the vehicle and the arm contraption between two people each, with Devin and I focusing on the arm, and Ibuki and Angel focusing on the vehicle, but we still moved in between when somebody needed help. After about two or three days of building, we had our prototypes built, both the arm and the vehicle, so we began testing, which did not go very well. At the start of testing, the arm only hit the vehicle straight about one meter, so we attempted adding more weights to it so it would have more force when it is dropped from a height. After adding  more weight, the vehicle went about 1.25 meters, so we decided that we needed to revamp our design. After some quick think by Ibuki and Angel, they built entirely new legs for the arm, essentially doubling the height, as well as changing the PVC pipe used for the arm to one that was much longer, which allowed us to be able to add more weights inside of it and only have to pull it back about half the distance we would have had too it we used the original design. After testing this new version, as well as adding a little area for our pennies to stay in when they traveled, the machine traveled either just over five feet, or turned about halfway. These imperfections were due to the placement of the arm connecting to the stopper on the back of the vehicle, but that can easily be fixed, so we took some videos so we could start our data graphing.

To graph the Distance vs. Time graph, the Velocity vs. Time graph, and the Acceleration vs. Time graph, we used a slow motion video to precisely track the time of the car moving when it hits each of the meter points, which gave us the basic Distance vs. Time graph. To get the Velocity vs. Time graph, we calculated the slope of each of the sections from the first graph, and to get the Acceleration vs. Time graph we calculated the slope from the second graph. With each one of those done, we started on our Energy Vs. Time graph. To get potential energy, we found the potential energy due to gravity, which meant we had a different process compared to all of the other groups. Then, we used that as the total energy for the entire graph, meaning that we just had to find kinetic energy and thermal energy. To find the kinetic energy, we just multiplied half of the vehicles mass by its velocity squared for each of the time marks, and to get thermal energy, we just subtracted those numbers from the total velocity since our potential energy was transferred straight to our car without having residual energy as it continued to swing. The largest change in thermal energy was right when the arm hit the car, because they had directly collided, generating a heat. Now that we had our graphs we began working on the slideshow, which you can view above.

Unit: Jules Variable: PEg Equation: PEg = magh

Potential Energy due to gravity is just what it sounds like, the possible energy an object has due to its height or position in a gravitational field. Our contraption utilized this energy as its main source of energy. We pulled the 0.855 kilogram arm 60 centimeters of from the ground, then let it fall so it could hit our vehicle, and utilize it current momentum to hit the vehicle in the same direction that the arm was traveling in. Since we got our energy from the arm, when the arm came it contact with the vehicle, it transfered most of its energy into kinetic and thermal energy, which is show in the immediate drop of potential energy in our graph.

Unit: Jules Variable: KE Equation: KE = 1/2mV2

Kinetic energy is the energy an object has due to its movement. In our graphs, the kinetic energy starts off with a large spike and then decreases because the arm hits the vehicle forward, resulting in a large change in the velocity compared to the other stages, but the kinetic energy does decrease gradually. The only limit the kinetic does not stay the same the whole time is because of friction. The friction of the wheels on the ground results in the vehicles decreasing velocity, which in turn leads to a decreasing kinetic energy.

Unit: Jules Variable: Etotal Equation: Etotal = PE+KE+Ethernal

The total energy is all of the energy an object has, but that energy is always changing. On our graphs, the total energy stays the same because the original potential energy is the same as the maximum amount of energy we could have since the arm was the only source of energy. But, after there is no longer potential energy, then the total energy also includes kinetic energy and termal energy.

Unit: Jules Variable: Eth Equation: Eth = Etotal-KE-PE

Thermal energy is the energy that is lost to heat. In our graphs, the most thermal energy our vehicle has is when there is no more kinetic energy, meaning that all the energy had been transferred to heat energy. At the start, when the arm hit the vehicle, there is the largest spike in thermal energy because there is a collision between two objects, compared to the gradual increase that it has right after the collision.

Distance vs. Time:

This graph is just saying the time point of when the vehicle past each meter mark, all the way up to its maximum distance and time, which was about 5.25 meters in 5.05 seconds. To get the time points, we took a slow motion video and used the edit feature to view the exact time the vehicle reaches a meter mark.

Velocity vs. Time:

This graph is saying the speed our vehicle is moving at each time point we found earlier, with the maximum being 2 m/s when reaching the first meter mark and then at 0 m/s when the vehicle had fully stopped at 5.05 seconds. We got the velocity at of each time point by calculating the slope of the Distance vs. Time graph at each one of those points.

Acceleration vs. Time:

This graph is saying how much the vehicle is speeding up and slowing down after each meter mark, with the maximum acceleration being 4 m/s^2 and the greatest deceleration being 1.282 m/s^2. Our acceleration graph looks the way it does because the arm hits the vehicle forward at a fast speed, meaning the graph will have its greatest acceleration at the start, and then the vehicle will almost instantly begin slowing down. After the initial acceleration, the graph never goes above zero because the vehicle does not begin speeding up again. We found the acceleration of the vehicle by calculating the slope of the Velocity vs. Time graph.

Rotational Inertia (I) how easy an object is to rotate, with lower rotational inertia being easier to rotate and higher rotational inertia being harder to rotate. to find it, you calculate the mass and its distance from the center of the object. This is why we stick out our arms to prevent falling because we are taking mass away from our center and spreading it out, causing us to have a greater rotational inertia.

In this project I think I could have done better in my Empathy and Communication skills. During certain aspects of the project, namely the slideshow, I struggled to accept the work that my classmates do, so I redo it so it lives up to my standards, and when I rewrote it, I often wrote too much, which meant I had to shorten it into fewer words or bullet points. Since I wasn't able to accept my classmates work yet again, I think that means that that is the part of collaborating in groups that I need to work on the most, and since I was unable to convey my point in a short simple way, I need to improve my Communication skills so I can make both my life and everyone else's easier when reading my work.

During this project, I think I again did very well in my leadership skills as well as collaborating with my teammates. I took charge, in generating the ideas for our design, as well as making sure things get built and completed, and since I believe I have done well most of the time in my leadership abilities, I believe that is my strongest skill. I believe I did well in collaborating with my teammates during this project because this was the first project where everyone wanted to contribute as well as help with what we needed to accomplish. People who think like that, I greatly appreciate, because that allows me as well as themselves to succeed in life, and it made it easier for me to work with them.