Christmas Crushers

Team Information

Car Name: Santa’s Sled

Team Name: Christmas Crushers

School Name: NSU University School

Team Members Names: Harper R. and Shivam K.

Design Documentation

Project Log

Date	Hours	Tasks	Obstacles Encountered	Modifications to Car
11/17	1	Learned about the competition. Looked at some sample cars. Drew the design for my car.
12/1	1	Cut the front of the piece of balsa wood for my body into a triangle hoping to improve the aerodynamics. I chose my wheels and axels.		Cut the car body.
12/8	1	Decided on black gears. I am putting a larger one on the motor and a smaller one on the axel. I decided on a long white panel instead of the blue one because the white one is lighter. I picked a small black binder comb to keep it on the guide wire.
12/15	1	Worked some more on my plan to decide where to put everything on the body. I used a t-square to draw lines on the body so that my wheels and axels would be straight and parallel.
1/5	1	I marked and hammered the gear onto the back axel and added the spacers and wheels. I marked the center and glued on the back wheels. I used a hammer to put together the front wheels with the spacers. I did not have time to glue them on.
1/12	1	I glued on the front wheels. I also worked on my circuit today.		Glued on front wheels
1/19	1	I finished my circuit (battery pack with switch connected to the motor). I glued on the battery pack and the motor. I got to test it for the first time in the hall on battery. It did not go straight. I had to adjust the wheels by heating the glue with the heat gun and moving the axel a little bit. My teacher is soldering the wires to the motor and alligator clips before next class.		Glued on battery pack and motor.
1/26	1	I added supports to hold up the solar panel and pieces of balsa wood to the sides to improve aerodynamics. I put cotton in the front to secure my ping pong ball.		solar panel supports, cotton ball in ball holder place
2/2	1	I put on the black binder comb. I decided to put one on each side to keep it balance and so I could run on either side. I put on the panel and tested it outside. It ran, but it seemed slower than the others.		Added black binder comb for guide wire. Put on solar panel.
3/2	1	I decided to try to improve the speed by changing the gears. I have to change the wheels, too, because the gears I chose will only fit on the thin axels.	The car did not go fast enough.	Decided to change the wheels from four large wheels to four small white wheels. Also, I am changing the black gears to white ones. The small one on the motor and the medium sized one on the new axel.
3/9	1	Working on the new wheels and gears. Finished with motor and back wheels and axel.		New back wheels with white gear on. Motor now has small white gear.
3/16	1	Front wheels on.		Front wheels on.
3/23	1	Tested car and it is not going straight.	Tried to adjust wheels so that it would go straight.
3/30	1
4/4	1	Tested car outside on solar panel.	Car is going slow and turning to the right.
4/6	1	I tested my car outside on panel.
4/7	1	Tested my car outside on panel.
4/19	.5	Ran my car on solar panel
4/20	1	School competition	The wheels fell off. I have to put them back on and make sure it is going straight.

Design Drawings

Design Drawings: Top View

Design Drawing: Side View

Finished Car Specifications

Car Size with Panel	Length: 33.0 cm	Width: 20.8 cm	Height: 9.5 cm
Weight with Panel	136.3 g
Wheel size	Front wheels: 3.6 cm	Back wheels: 3.6 cm
Gear Ratio	motor gear: axle gear 14 : 48 = 7 : 24

Materials Used

Material	Approx. Cost
New:
Solar Made solar panel	20.99
Motor	2.50
small white gear (from motor mount pack)	2.50
wheels, tires, axles, axel gears – Solar Made accessory bag	4.50
balsa wood	2.31
spacers for bearings (4)	0.26
battery holder with switch	3.85
pieces of black binder comb, 1 inch	0.07
velcro	0.14

Consumables:
masking tape
hot glue
solder

Recycled:
cotton
styrofoam

Test Results / Trial Runs

Test Runs 1 – date: 4/4/2022
Weather conditions: Partly cloudy
We ran it on panel when the sun was out.

Observations of results: The car is going too slow. It is also going a little to the right.
Any recommendations for improvements: I am going to try to change the gears so that I have a small gear on the motor and a medium gear on the axel.

Attempt	Time, s	Distance, m	Speed, m/s
1 – panel	9.5	14.5	1.53
2 – panel	10.2	14.5	1.42

Test Runs 2 – date: 4/6/2022
Weather conditions: Cloudy
We had to run on battery.

Observations of results: It is running much better with the new gear ratio. It is running straight now too.
Any recommendations for improvements: I have to try it on panel now.

Attempt	Time, s	Distance, m	Speed, m/s
1 – battery	6.6	14.5	2.20
2 – battery	6.8	14.5	2.13

Test Runs 3 – date: 4/19/2022
Weather conditions: Sunny and clear
All my runs were on Panel today

Observations of results: It is going straight but I have to make sure I set it up straight. This is a shorter track.
Any recommendations for improvements: I am going to try it on a longer track.

Attempt	Time, s	Distance, m	Speed, m/s
1	4.87	10	2.05
2	3.40	10	2.94
3	3.65	10	2.73

Test Runs 4 – date: 4/19/2022
Weather conditions: Sunny and Clear
Ran on Panel

Observations of results: I ran it on the longer track and it went straight.
Any recommendations for improvements:

Attempt	Time, s	Distance, m	Speed, m/s
1	5.41	14.5	2.68
2	5.38	14.5	2.70
3	5.31	14.5	2.73

Test Runs 5 – date: 4/20/2022
Weather conditions: Partly Cloudy
We ran on both Panel and Battery depending on if the sun was behind the clouds

Observations of results: The wheels fell off now my car is turning right and I think the guide wire is rubbing. I wasn’t able to do my 3rd time trial.
Any recommendations for improvements: I am going to move the front wheel on the left down to try to straighten it. I will try a different size guide wire guide.