1. Define the Problem
What need or want must be met by the solution?
Create a car with minimal drag and surface friction for the best speed.
In the space provided, sketch three possible solutions to the given problem. Remember to be creative!
3. Research and Generating ideas
Notes:All land vehicles are systems made from power, suspension, guidance, control, structure and support subsystems. Jet engines create force or thrust by heating air that quickly expands and escapes from a nozzle. Suspension connects the vehicle to the environment. The guidance system provides information to the operator to help guide him/her to his/her destination. Speedometers in cars provide information about vehicle speed. Throttle, steering and braking subsystems control the motion of land transportation vehicles. The throttle subsystem controls the power plant to increase or decrease speed. Steering systems provide drivers with a means to turn the vehicle left or right. To stop, brakes are attached to wheels. Braking systems use friction to slow a vehicle. The vehicle's chassis provides the structure that joins together the power, suspension, guidance and control subsystems. The chassis is designed to hold all of these subsystems while overcoming forces that could cause failure. Chassis designs vary depending on the purpose of the vehicle. There are three basic vehicle chassis designs - Ladder, Tubular Space Frame and Unibody. The Ladder Chassis is made from two or more rails connected by a cross brace. It's like a ladder. This system was commonly used in automobiles through the 1970's. The Tubular Space Frame is a light, stiff and safe chassis design. The frame uses steel tubes welded together with diagonal braces. The Unibody Chassis is made of sheet metal integrated into the design of the car. Sheet metal welded together forms tubes, beams, braces and other structural elements to make a system that is relatively light and stiff while protecting passengers. The support subsystem is not part of a land transportation vehicle. Rather it is the components that provide the energy and infrastructure that keep vehicles operating. Cars need roads and maintenance for continued safe driving. Like all technologies, with the good there is also bad. The fuel that powers our transportation systems is made from oil. Oil is a nonrenewable resource - a resource that cannot be replaced. To go fast, acceleration is the key. The faster the car accelerates the greater the speed. An increase in force (F) will increase acceleration. Acceleration will also increase by decreasing mass (m). 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.
4. Criteria and Constraints
What are the criteria and constraints?
- criteria and constraints-
- must travel down 20 foot track
- The size of the dragster you design must comply with the following specifications.
Height with Wheels
Width at Axles
Total width including wheels
Mass (without CO2 cartridge)
Number of Axles
Bottom of axle hole above car bottom
Rear axle hole from car rear
Wheelbase (measured at farthest point)
- Bearing, bushings and lubricants may be used.
- Glue may not be used to hold wheels and axles in place.
- Dragster must have 4 wheels.
- The hole must be drilled so it is parallel to the track surface.
- The 4mm minimum wall thickness is required for safety.
- Only cartridges provided by your teacher may be used.
- Screw eyes must not contact the race track.
- Glue may be used to reinforce the screw eyes.
- Screw eyes must be tightly closed to prevent string from slipping out.
5. Exploring Possibilities
I made the design more slender and decreased the weight. Also i moved both sets of wheels inside the car for less drag to increase speed exponentially
6. Selecting an approach
Constraint Design 1 Design 2 Design 3
Materials 2 2 3
Time 1 2 3
Weight 1 2 3
Surface friction 2 1 3
7. Developing a Design Proposal
9. Tests performed
10. Refining the Design
In order to make the fastest car the design must be streamlined in order to reduce drag down to nothing and the lightest materials for the best speed.
11. Creating or making it
To make this you would need a mold for the chassis of the car and a lot of CO2 cartridges to fuel the cars. once the mold is cast and you have the cartridges all you need is the wheels and your ready for the market.