S: The ITS
FC: The ITS The Creation of a Rat ESCAPE Car Monday, October 20- Wednesday, November 5 | By: Kylie, Jessica, Marna and Jeremy
1: The Design Monday, October 20
2: This is the design that we made on the first day of plannning.
3: These diagrams are to help you further understand our car.
4: Reasoning The reason we chose this method, is because we knew what the forces were and how they were being used.
5: One end of string is attached to the lever arm. The other side is connected to a dowel between the back two wheels. When the car is pulled back, the string wraps around the dowel in the back. When the car is released it will unroll the string and will be propelled forward. | How it Works
6: The wheels that we are using are 2 inches in diameter. Seven were made in case of damage to others or using double whells to make it sturdier. | Wooden Wheels
7: Construction Time Tuesday, November 21- Thursday, November 23 | We applied 13 inches of a yard stick to each side of the trap, using nails. Once that was done we made holes for the dowels to go through in the back. | Then the wheels were added. On the front however, no holes were made due to the factor that only one wheel was needed and nothing had to be attached there. It was secured with duct tape.
8: Testing The First Try Thursday, October 23
9: On the first trial,we used 12 inches of string. When we wound it up it snapped closed, but it did not go anywhere.
10: WHAT'S WRONG WITH THIS THING?! Friday, October 24
11: We had no idea what was wrong with our car until we looked at our diagram again. One thing was wrong. We had one end of the string connected to the dowel between the back wheels and the other side to the edge of the trap. When we looked over the diagram, there was supposed to be a lever connected to the metal snapping object. Once we made this adjustment, it worked.
12: First Modification Friday, October 24
13: The wooden dowel added as a modification as a lever to the metal snap part of the trap by using duct tape. The dowel was about 4 Inches long.
14: The Second Modification Friday, October 24
15: The object that held the other end of the string, between the back two wheels was taken off.
16: Testing The Second Try Friday, October 24
17: On the second test, the car went forward about 4 inches. Then when it was set up the opposite way, it went about 6 inches. It went straight and did not curve at all.
18: The Third Modification Friday, October 24
19: After seeing that the car worked after the dowel was added, we thought that it may go farther with a longer dowel... so that's just what we did. We extended the size to almost 3 feet.
20: The Fourth Modification Friday, October 24
21: Also after seeing the car at least moving, we figured that if the string was longer it would probably go farther. We increased the length to 24 inches.
22: Testing The Third Try Friday, October 24 So when the car first moved, how far did it go? | The Second Modification On this second trial run we also added more string, the total amount was 24 inches.
23: On the first run it went a total of about 2 meters in approx. 1.25 seconds. It didn't curve at all. | When it was first tested, it was on Friday, November 24 | The data was recorded was on Monday, November 27 | This video/ picture was captured on Monday, November 27 | To view the video navigate back to the website and click "The Third Test" video. After you view it come back to the book.
24: What else happened during the third test?
25: When we watched our trial again, we saw that there was still string wrapped around the dowel. It stopped because the duct tape on the inner part of the back, was rotating into the holes. Creating drag and making it stop.
26: Testing The Fourth Try Tuesday, October 28
27: After we added the longer dowel, which is almost 3 feet long, we tested it. It went straight almost everytime. It went about 3 meters. To view the video navigate back to the website, under "Test Three".
28: The Rebuild Thursday, October 30th
29: As a group we decided to remake the whole trap so we started from scratch again. So we decided that it was Jessica's turn to take the trap home and work on it. | Jessica took the car all apart so it was only the trap. she bought wooden wheels, 2 sticks,& a boarder for the car. Then Marna came over and we put the car together.
30: So... How'd it end up working out?
31: Well the answers to that question is... not so good. There was no dowel in the back in which to tie that string around and give the car a pushing force. | So we improvised. We took the wheel off and improvised. It is now going to.... FLY!
32: How is a rat trap supposed to fly?!
33: That's a good question and I'm going to tell you how. One end of the string is going to be attached to the ceiling. Then the other end is going to be held past the finishing line of the race way. | View the diagram on the next page.
34: The NEW Diagram
35: The trap has two pieces of wood on each side. Where the wheels used to be attached. The sticks holding the object in the air, are the metal sticks that holds spring part of the trap back. The object in the air is a spring from another trap, inside is a part of a straw to put the string through, making less friction between the two rubbing objects.
36: Newton's Laws An object in motion will stay in motion unless an outside force acts upon it. | Newton's law
37: In one of our tests, we had the string that the car flew on too low. Even though the car was moving well, the car hit the ground. The body in motion is the trap. The outside force acting upon it, is the ground.
39: The Graphs
40: This is the Acceleration Graph
41: This is the Velocity Graph