Monday, November 19, 2012

Reflection

On the day of testing, we saw many different designs. Some of them were vehicles we would never think of to build-- the Mousetrap was among the many. Their group used an actual mousetrap with a fishing fishing wire attachted to it. It was observed that the wires were winded around the back axels of the cars resulting in the total distanced traveled of 29 tiles. There were others with ideas that we had both considered using or had used; in the long run. we realized they wouldn't work or go as far as we were aiming for. Similar to us, many other people had balloon powered cars as well. Out of these, a few worked, but there were some that would not even move. A possible cause could have been that the balloon was facing in a way were its air flow was either being restricted or in the wrong direction.

Our car worked well at first, but kept turning around at around the fourth/fifth tile. If it had kept going straight, the vehicle would have definitely gone the distance of eight tiles, or so recorded from previous testing. If this project was done over again, something that would have been added is another set of small and light wheels in the front. Even though this would result in more mass and create more friction, the front wheels may have stopped it from turning. If we had kept the car with only two wheels, part of the draft that could have been changed would be the balloon. Instead of just letting go of the balloon, there could be, like another team had thought of,  two straws put into the hole of the balloon, limiting the air flow, yet making the wind stronger and more precise the whole time. This design was actually thought of and tested earlier, but we only used one straw and it didn't work, so we moved on to another idea without adding the number of straws. This project can help in further investigations about real cars or machines used for transportation in general. For example, when air comes out of the balloon, its backward force pushes the vehicle forward. This is the same type of way a rocket travels because the fuel of the rocket sends the airship flying as well..

Sunday, November 18, 2012

Day 4: Final Draft's Concepts

Mini Lab Report 1:

If the vehicle is powered by a rubber band, it will travel farther than being powered by a balloon.

Previously, before the making of our final draft, many different possible vehicles were made. One being powered by a rubber band was among the many designs and creations. As mentioned in previous entries, the rubber band scooter had actually traveled a small distance of barely 3 centimeters. As a backup plan, the contruction of a balloon-powered car was taking place. Some of the parts from the rubber band car were being used-- recycling and reusing. The chopstick was the new idea as the base, so that the balloon would be able to fit between the wheels. Soon the vehicle was completed, and the balloon had deemed its power of force sufficient.

It was discovered that the hypothesis was wrong because using the rubber band as the source of power made the vehicle travel less distance than being powered by a balloon.
 

Mini Lab Report 2:

If there are two wheels on the vehicle, then it will have less mass, less friction, and will travel farther.

The idea of two wheels was chosen while brainstorming for a new scooter that would incorporate the power of force as the balloon; it was based off of a segway scooter. After getting a chopstick, two of the CD wheels from the old rubber band scooter were carefully taped to the stick(the chopstick was in between the two CDs). Then, a straw was cut through one of its sides and taped to the chopstick(which was a step that was ,soon discovered, supposed to be right before taping on the CDs). The plan was to attach the balloon to the scooter. The straw was there so that when the balloon is taped to the vehicle(the straw), it wouldn't spin with the taped chopstick and CDs. Although it still had some tweaks, the scooter had traveled much faster than the car powered by the rubberband with the four heavy CDs.

The hypothesis is proven to be true because with three to four wheels, they were always bound to the risk of not moving at all because it was heavy from producing too much friction.

Mini Lab Report 3:

If a soda top was used to hold the balloon in place, then the vehicle will move in a straight line.

One of the main tweaks(as mentioned above), was the scooter's inabiliy to travel in a straight line. To solve this, the layout of the draft had included a soda lid taped to the straw. The lid was aquired by going to McDonalds. Before taping it on, the place to usually insert the straw was cut off, in case the pointy plastic would stop air flow or pop the balloon. Out of all the 10+ tests, there were only a few that had the scooter traveling in a straight line-- though when it did, it was very successful.

The hypothesis and idea is unreliable and proved to sometimes be incorrect because even though the balloon was positioned in a way that would release a straight airflow, the end of the balloon let out an uneven stream of air, making the scooter swerve/turn midway.

Summary:

During the construction of the scooter vehicle, there were some changes to the drafts. At first, we were going to have the vehicle being composed of 4 wheels. It didn't work as well as we wanted to have, so we just took 2 of the CDs off. Ideas of trying to not use the soda lid were used as well. There was also thought and testing of a design where the balloon(s) would be in front of the scooter and attached by a string. This was a possibility of a draft because there was a risk of the balloon touching the wheels. causing the scooter to slow down and actually made the car go backwards.

 

Concepts Applied:

Newton's 2nd law of acceleration and mass is applied to this vehicle because since the mass of our scooter is small, the amount of net force needed to move the object a far distance is far as well. The law of action and reaction forces are used by the car, too. Because the balloon's air is pushing the vehicle(action force), the vehicle is basically pushing the air(reaction force) for an equilibrium.


The pair of us had previously built a car that was powered by winding back a rubber band around the wheel's axel. Although this design had failed miserably, along with our current vehicle, it still had the same concepts of kinetic and potential energy. When winded back, the car had much potential energy. There was kinetic energy in both scooters as well; the rubber band/blown up balloon allowed the vehicle to move, and kinetic energy has to do with moving objects.

Day 4:Victory!!

Our vehicle was able to produce a result that we were proud of,
 even if it was stopped by a shoe!(trial 5) We didn't know that it would travel that far, so perhaps that's why we didn't clean that much of the hallway.

Trial
Distance(cm)
1
157.5
2
175.5
3
290
4
145
5
392

The scooter had traveled in a very straight line. We don't know if the balloon and snooter will be able to produce this result again, but it is hopeful.

Day 4: Testing and Revision

Meeting up again, we finally got to test our --not so-- hopeful vehicle. The first few tests that weren't recorded didn't quite go in a straight line. The scooter kept on turning and, in the end, moved backwards. There were also problems with the balloon dragging on the ground, resulting the scooter to come to a stop. To fix these problems, some adjustments were made:

  • sticking straw through the balloon(though that didn't work...).
  • making the hole of the soda top smaller by adding on tape(though that only restricted more air from coming out of the balloon; the vehicle traveled even less).
  • blowing up the balloon more, hoping that the air would release powerfully in a straight stream(but it wasn't much help either).
  • lathering the bottom of the balloon with water (which didn't really work)
  • Putting a paper (which we thought had less sliding friction) underneath the balloon (but there was even more friction from that, causing the scooter to travel less).

Final Design Draft

Final Draft

Saturday, November 17, 2012

Day 3: Perseverance Paid Off... Kind of.

Good News: After seven hours of precious Saturday hours, we built a vehicle that could go more than a foot.

Bad News: We spent seven hours building a car that still does not meet the requirements. 

`.`

"This is pure despair"
               -Emily Kang