Holly Campbell
Multidisciplinary Engineering Laboratory: EG498A -- Legos
Individual Project Idea
due Sept 8, 1995

Light Detecting Avoidance Vehicle

The main purpose of the Lego lab is to find a variety of engineering projects that specifically show different aspects of engineering. One of the major factors is making the projects easy enough for a student at the Freshman level to complete and understand. I feel that this particular guideline is the most difficult one to follow. As Senior engineers, we have accumulated a sufficient supply of knowledge, and when all of our different majors are pulled together, that amount is vastly increased. While our ideas are flowing and each individual is adding aspects from his or her own experience, it is difficult to keep in mind that these freshman will have very little knowledge. After brainstorming and discussing my ideas with other peers, I decided to elaborate on a project which is patterned after a wartime defense vehicle.

A vehicle would be designed whose main purpose would be to detect "enemies" and decide on the best path to avoid these enemies. At the same time, the vehicle attempts to find the quickest way across enemy territory to the safety post on the opposite end of the field.

There are numerous ways to attack this problem, but I will simply explain one in detail. In this case, the field could be a table top, or a taped off area on the ground. Stationary enemies that emit either strong light or infrared light would be placed within this area. As the vehicle approaches such an enemy, it would detect the light, and then, based upon the angle at which the light was detected, would calculate where that beacon was and avoid it by maneuvering, possibly through a 'back up and turn' sequence until the enemy is passed. A variation of this would be for the vehicle to detect a number of beacons at one time, and determine, based on all of the locations, a best path.

Different types of engineering are inherent in this project, if not directly, then indirectly. For example, a vehicle must be built that can turn easily and in a small spatial area. This criteria is very important, because it would mean "death" if the vehicle backed up into another enemy! The design of such a vehicle brings in the mechanical aspects of engineering. Programming is also very crucial to this task. The vehicle must be made "smart" so that it can detect the light sensors, determine a best path based on the data it receives, and then tell other parts of it's structure to turn in the correct direction, move for the correct amount of time (until these lights are passed and/or new ones detected), or stop, if it determines the goal is reached. An algorithm that makes efficient use of the space given and determines the quickest path must be designed. I foresee this as being the most difficult aspect of the project.

The path finding algorithm is probably the best indirect way of linking this project to other types of engineering. Of itself, it requires programming, but an underlying algorithm must be designed, and path finding algorithms can be incorporated into many different forms of engineering. For example, an aerospace engineer may use such an algorithm to determine the best path for a jet through the clouds, or at low altitudes, through the mountains. It is also possible to relate it to electrical engineering and circuit design. For a circuit to run faster (if only by a little bit), it is best for the wires connecting the various components to be as short as possible, and so a shortest path must be determined for each of these wires (picture the IC components as the enemies to be avoided).

Through design of this project, freshman would not only learn how to solve engineering problems, but he or she would also have fun. This project is designed with a concrete beginning and end, but the intermediate method is open to individual design. The students would be challenged with the goal of getting that vehicle to the other side of the field in the shortest amount of time. If they determine that can be done by only detecting one enemy at a time, or many; if they choose to design their algorithm to choose a path that continues in the vehicle's current direction, or if they decide that it is quicker to turn the vehicle; whatever they decide, it will be their decision, their design, and their determination that makes this project work.