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# CO2 CAR

1) Define A Problem - Design a CO2 car to max speed

2) Brainstorming-

3) Researching and Generating Ideas-

Travel over land has been a necessity of people and animals since the beginning of time. Traveling faster and further gives both people and animals advantages. For animals, predators need speed to run down prey for food. For people, travel allows us to transport food and supplies to support life.Throughout history people have used technology to overcome limits on their physical abilities. The most common power plant used in land transportation vehicles is the internal combustion engine. Internal combustion engines are used in the cars and trucks we use every day.When the piston comes back up the exhaust from the explosion is released. Hence the four strokes: 1) Intake, 2) Compression, 3)Power, and 4) Exhaust.Suspension connects the vehicle to the environment.The guidance system provides information to the operator to help guide him/her to his/her destination. Accelerate, turn, stop - vehicles need subsystems to control motion. What makes a CO2 dragster go fast? If you want to design the best dragster, you need to know what design factors make CO2 cars perform. Acceleration is related to velocity, but they are not the same. Mass is related to the weight of the vehicle. Mass is a measure of the amount of matter or material an object contains. The center of mass is an object's "balance point".The center of mass helps us understand how an object will behave when external forces are applied. In an automobile, if the center of mass is high, the vehicle will tend to flip when going around a corner.There are two categories of force that will affect your design - positive and negative. Positive forces accelerate (or push) the dragster toward the finish line. Negative forces decelerate (or pull) the dragster away from the finish line. The cartridge force is a positive force, while surface friction and drag are negative forces.Resistive forces are the forces working against or resisting the forward motion of your dragster. Friction occurs when two surfaces are in contact and a force is moving one surface over the other.Rolling friction is a force that resists the motion of wheels or balls.Now that we know the normal forces at the front and rear wheels, we can calculate friction forces that apply when the car is in motion. Drag occurs when a solid object moves through a gas or liquid. When your dragster is streaking down the track, air flow creates pressures and friction on the vehicle. Like surface friction force, drag force is a negative force working to slow your dragster. The sources of drag are pressure and friction. Pressure drag (CD(Pressure)) is the difference in the high pressure pushing on the front and low pressure in the rear of a vehicle. Streamlining involves changing the shape of an object to reduce pressure and friction caused by air flow. Frontal area is what the air stream sees or what you see looking at the front of a car. The force from the cartridge (FC) is working to move the car forward. Drag (FD) and friction (FF) forces are working against this force. To maximize the net force, the equation tells us to increase the cartridge force and/or reduce the forces of drag and friction. Drag force depends on velocity, and velocity changes throughout the race. In fact, since drag increases with the square of velocity, drag can change quite a lot.

Citations/References:

Whiteboxlearning.com

4) Identifying Criteria and Specifying Constraints -

Body Minimum Maximum Designed Length 202 mm 303 mm 285.4 mm

Height with wheels--73 mm 70.1 mm

Width of body at front axle 36 mm 42 mm 37.5 mm

Width of body at rear axle 36 mm 42 mm 41.2 mm

Total width including wheels--88 mm 54.0 mm

Mass (without CO2 cartridge)43 g--44.37 g
Axles and Wheelbase Minimum Maximum Designed

Number of axles 2

Bottom of axle hole above car bottom (front)5 mm 8 mm 5.1 mm

Bottom of axle hole above car bottom (rear)5 mm 8 mm 6.9 mm

Rear axle hole from car rear 10 mm 98 mm 74.2 mm

Wheelbase (measured at farthest point)108 mm 268 mm 154.8 mm

Space Washers 8 Manual Axle Clips 8 Manual
Wheels Minimum Maximum Designed Front Diameter 31 mm 36 mm 35.5 mm

Front Width 2 mm 5 mm 2.0 mm

Rear Diameter 30 mm 40 mm 39.2 mm

Rear Width 13 mm 18 mm 15.4 mm
Power Minimum Maximum Designed

Hole Depth 50 mm 52 mm 51.0 mm

Wall Thickness 4 mm--4.1 mm

Chamber Diameter 19 mm 20 mm 19.5 mm

Lowest point of hole to race surface 28 mm 38 mm 34.0 mm
Eye Screws Minimum Maximum Designed

Inside Diameter 35 Manual Distance Apart 155 265 Manual

5) Exploring Possibilities-

6) Selecting an Approach

7) Developing a design proposal

8) Making a model or prototype

9) Test and evaluating the Design

10) Refining the Design

The thing i would fix is the mass

11) Creating or Making it

I would make it aerodynamic