The BIG IDEA

DRAG RACE

Objective:

To make a lego car move along a straight track as quickly as possible

This lego objective provides the freshman with an opportunity to have fun while incorporating engineering principles in designing and constructing a race car. In the development of a car, students can determine the intricacy of the project for themselves. Yet they are stimulated by the competitive aspects of a drag race, thus pushing each other to make better designs. Therefore, the motivation for the development of this project is to show that complex designs (ie. lego transmissions) can actually outperform the simple designs.

Developers' Goals:

The Developers of the project must develop a set of rules for the race. These rules would include a few of the following items

1. The match will consist of three head-to-head races
2. Only pieces crossing the finish line can compete in subsequent races
3. The match-ups will be coordinated such that the competitors will have raced the same number of times (because of battery drainage)
4. Cars must stop within a defined braking area or be disqualified from the race
5. Cars may cause no impedence to other racers, on penalty of disqualification
6. All parts must start behind the starting line, the winner determined by the first piece the reach the finish line
7. Cars may use a groove in the race track for directional control--all emphasis is on speed, not steering
8. The track will be painted one color, the finish line in another so that the car can detect the end of the race
9. The start will be signalled by a light shining from beneath the race track

These rules are subject to change. Interesting and, for the most part, intentional loopholes exist in this race structure. For example, cars could be equipped with arms which extend beyond the front of the body, like a sprinter leaning at the finish line. However, the emphasis of the project would be on speed and not tricks. The means toward this end include weight minimization and gear shifting.

The Transmission

Since the car must carry the MIT/Motorola processor board and the battery pack, and the motors provide limited power, a large input/output gear ratio must be used in order to start the vehicle moving. As the car gains momentum, lower gear ratios are necessary to keep the vehicle moving and to accelerate the car further. Thus a transmission can be used, controlled by the processor board, to increase the overall speed of the vehicle. A simple 3 gear prototype transmission is shown at the right. Other transmissions will tested and developed to give insights to the freshman competitors.

Student Objectives:

Using the available pieces, the freshmen must design and construct a vehicle capable of finishing the race. Then, expanding on this design, the students must optimize it for speed, most likely by incorporating a transmission. Also, the vehicle must be able to stop within the required length. Back to the Proposal