Over IAP 2004, I participated in 6.186, an autonomous robotics competition commonly known as MASlab (Mobile Autonomous Systems Laboratory). I formed a team with three then-freshmen from my hall: I was in charge of the design and construction of the physical robot, while my teammates were responsible for the programming and sensors. The goal of the contest was to travel around a playing field, collecting red balls, and green tubes full of three red balls, take these to a yellow scoring zone, and then deposit the balls in the zone.
The robot was a sort of "Hungry-Hungry Hippo" design that took everything in its path into the chamber inside, and then pushed everything back out when it got to the scoring zone. This design was chosen to maximize the number of balls that could be carried, and thus maximize the number of possible points per trips between scoring zones. There was a gate in the front to keep objects inside the chamber, and the back wall of the chamber moved forward when the balls and tubes needed to be expelled in the scoring zone. The back wall was mounted on a rack and pinion system, with the motor that drove the pinion gear mounted to the wall itself, and the moments generated by the weight of the motor and movement of the pinion balanced by a roll of nickels. The size of the chamber made the it impossible to mount the drive motors in the front of the robot, due to size limitations imposed by the contest, and so we used a timing belt and pulley system to have front-wheel drive. This had the favorable effects of an easier to control front-wheel drive system, as well as putting the camera in the plane of turning, making the programming of the robot easier by simplifying or eliminating translating between the robot control and the visual analysis.
Unfortunately, I think I took on too much of the design and construction myself, resulting in the physical robot not getting finished until a week or so before the contest (you can read my very detailed daily journal on the course wiki). So, I didn't really give the programmers enough time to finish up and troubleshoot their code. In the contest the robot malfunctioned, and ended up slamming itself repeatedly into a wall. On a second, unofficial run, the white-balancing code was fixed (the lighting in the lecture hall where the competition was held was different than the lighting in the lab), and the robot did collect some balls on the field. Overall, I was satisfied with the design, but I learned a lot of important lessons about working in a team. Finally, in case you're wondering, the robot was named after one of our hall mates who liked to make "your mom" jokes. Also, the photos on this page were adapted from those on the MASlab website (we were team 12).