CO2 Dragster
Problem
Create the quickest CO2 dragster.
Generate Ideas
-Spoiler
-Curved front and back
-Thin wheels
-Back tires larger than front tires
-Back tires thicker than front tires
-Notched wheels
-Curved front leading to a hole in the bottom of the car
Constraints
Measurements:
Create the quickest CO2 dragster.
Generate Ideas
-Spoiler
-Curved front and back
-Thin wheels
-Back tires larger than front tires
-Back tires thicker than front tires
-Notched wheels
-Curved front leading to a hole in the bottom of the car
Constraints
Measurements:
-Must have hole located in the back in order to hold the CO2 cartridge
-Car can only be made out of balsa wood and paint
-Can only use the tools provided in class in order to create your car
Criteria
-How much does it weigh? The lower the weight the lower the friction.
-How simple is the design? The simpler the design the less chances for error.
-How aerodynamic is the car? The more aerodynamic the less drag the car has to battle.
-How much downforce does the car create? The more downforce the better because the wheels will stay on the track.
Research
Searched using phrase "What makes a good CO2 dragster"
-Has to have the right amount of friction, too much or too little and the car will slow down
-In order to have a low amount of friction the car must be lightweight
-In order to move fast the car must have little drag, because as air hits the car it will be pushed back, therefor slowing it down
-The more aerodynamic your car is the less drag because wind will go around the car rather than hitting it and pushing it back
http://auto.howstuffworks.com/auto-racing/motorsports/co2-powered-dragster2.htm
Possible Solutions
Idea 1: Create a C02 dragster that has a spoiler on the back and has bigger wheels on the back axle than on the front axle. Combined the spoiler and the bigger wheels on the back create down force that will make the car go faster when tested.
Idea 2: Create a CO2 dragster that is curved on the back and front along with thicker wheels on the back than on the front. This will make the car more aerodynamic, making it go faster.
Idea 3: Create a CO2 dragster that has a curve on the front that leads into a hole on the bottom of the car to displace air. Create notched wheels so that the car's wheels have less surface area touching the track or ground, therefore less friction making the car faster.
Idea Matrix
-Car can only be made out of balsa wood and paint
-Can only use the tools provided in class in order to create your car
Criteria
-How much does it weigh? The lower the weight the lower the friction.
-How simple is the design? The simpler the design the less chances for error.
-How aerodynamic is the car? The more aerodynamic the less drag the car has to battle.
-How much downforce does the car create? The more downforce the better because the wheels will stay on the track.
Research
Searched using phrase "What makes a good CO2 dragster"
-Has to have the right amount of friction, too much or too little and the car will slow down
-In order to have a low amount of friction the car must be lightweight
-In order to move fast the car must have little drag, because as air hits the car it will be pushed back, therefor slowing it down
-The more aerodynamic your car is the less drag because wind will go around the car rather than hitting it and pushing it back
http://auto.howstuffworks.com/auto-racing/motorsports/co2-powered-dragster2.htm
Possible Solutions
Idea 1: Create a C02 dragster that has a spoiler on the back and has bigger wheels on the back axle than on the front axle. Combined the spoiler and the bigger wheels on the back create down force that will make the car go faster when tested.
Idea 2: Create a CO2 dragster that is curved on the back and front along with thicker wheels on the back than on the front. This will make the car more aerodynamic, making it go faster.
Idea 3: Create a CO2 dragster that has a curve on the front that leads into a hole on the bottom of the car to displace air. Create notched wheels so that the car's wheels have less surface area touching the track or ground, therefore less friction making the car faster.
Idea Matrix
Mathematical Model
Based on the results of the races I was able to determine that the fastest cars were the cars that weighed the least amount. I also determined that the fastest cars were also the most aerodynamic as their designs had a lot of curves and very few straight edges.
Summary
I am choosing to build Idea 3 as my CO2 dragster because the problem is to create the quickest CO2 dragster and Idea 3 is the quickest. Idea 3 is the quickest because it has the least amount of drag by displacing air to the bottom of the car, it also has the least amount of friction because it has notched wheels that reduce the surface area that is touching the track , thus reducing the amount of friction. I will also add a spoiler to Idea 3 in order to create max downforce to keep the car on the track. Idea 3 is also the most lightweight out of all of my ideas making it superior to Idea 2 that is very heavy due to the thick wheels. Lastly I did not choose Idea 1 as it was too simple and I believed that it did not have enough components in order to make it the quickest CO2 dragster.
Graphical Model
Based on the results of the races I was able to determine that the fastest cars were the cars that weighed the least amount. I also determined that the fastest cars were also the most aerodynamic as their designs had a lot of curves and very few straight edges.
Summary
I am choosing to build Idea 3 as my CO2 dragster because the problem is to create the quickest CO2 dragster and Idea 3 is the quickest. Idea 3 is the quickest because it has the least amount of drag by displacing air to the bottom of the car, it also has the least amount of friction because it has notched wheels that reduce the surface area that is touching the track , thus reducing the amount of friction. I will also add a spoiler to Idea 3 in order to create max downforce to keep the car on the track. Idea 3 is also the most lightweight out of all of my ideas making it superior to Idea 2 that is very heavy due to the thick wheels. Lastly I did not choose Idea 1 as it was too simple and I believed that it did not have enough components in order to make it the quickest CO2 dragster.
Graphical Model
Working Model
Progress
I was able to finish building my CO2 dragster in one day, however I had to change some components of the design due to mistakes while building and the design not being practical. The first thing I did was trace my template onto my car and then I drilled my axle holes. After this I went to the band saw to cut the shape of my car. Unfortunately while cutting my car I missed the line on my template and cut way too low. Due to this I came dangerously close to the CO2 compartment and could no longer chisel the ridges on each side of my car or I would run the risk of accidentally cutting into the CO2 compartment and ruining my car. After this I sanded down my car using each type of sand paper and then curved the edges of my car by using a curved sanding block.
Pictures
Progress
I was able to finish building my CO2 dragster in one day, however I had to change some components of the design due to mistakes while building and the design not being practical. The first thing I did was trace my template onto my car and then I drilled my axle holes. After this I went to the band saw to cut the shape of my car. Unfortunately while cutting my car I missed the line on my template and cut way too low. Due to this I came dangerously close to the CO2 compartment and could no longer chisel the ridges on each side of my car or I would run the risk of accidentally cutting into the CO2 compartment and ruining my car. After this I sanded down my car using each type of sand paper and then curved the edges of my car by using a curved sanding block.
Pictures
Results and Changes
I raced my car in Lane 2 against Akhil and was able to win all 3 heats with my fastest time being 0.736 of a second. From this time I was able to determine that my car was the 5th fastest car in my class mainly due to it's lightweight. Based on the results of my car and others I was able to determine that the fastest cars were the ones that weighed the least. Because of this if I was to redesign my car I would make it shorter and make a lot of cuts on the bottom of the car in order to reduce weight while still staying within the guide lines.
I raced my car in Lane 2 against Akhil and was able to win all 3 heats with my fastest time being 0.736 of a second. From this time I was able to determine that my car was the 5th fastest car in my class mainly due to it's lightweight. Based on the results of my car and others I was able to determine that the fastest cars were the ones that weighed the least. Because of this if I was to redesign my car I would make it shorter and make a lot of cuts on the bottom of the car in order to reduce weight while still staying within the guide lines.