Jerry Sanders Creative Design Competition
The Jerry Sanders robotics competition is an annual tradition taking place at the University of Illinois during Engineering Open House. For the 2002 competition, we formed a team consisting of myself, two Electrical and Computer Engineers, and an Aerospace Engineer.
The challenge was to compete with other robots to pick up Bocce and Bowling balls from 2-3 inch tall PVC pedestals, and return them to a "home-base" area. Our design was pretty simple - a big rectangular robot with a pulley-based center chamber. Essentially, there were two channels which could be slid under the ball. As the chamber was lifted, the ball would get caught in the groove of the channel, and roll down.
In the case of the Bocce balls, there was an opening in the back which lead to a holding tank of sorts. We had capacity to get at least half of the balls, which would be a major accomplishment considering. The bowling ball would be held in the back of the lifting chamber itself. Once it hit the back, it would effectively lock in place. This would allow us the chance to place the bowling ball on the pedestal in the home area for double points.
Besides being the main welder for the project (a skill that I picked up solely for the project), and being involved in the actual design, I was also responsible for writing the software to control the robot. In order to keep things simple, we had decided to use a pair of laptops - one on the robot connected to the control circuit, and one with us to act as a controller.
Unfortunately, until the night before the competition, we didn't have a working robot; as a result, I had devoted most of my effort to helping try to get things working, rather than writing the control system. In the end, I wound up writing a simple control system which ran over the wireless network and controlled the robot.
Unfortunately, with no mechanical engineering types on our team, our design was plagued with drive issues. Upon going over a small drop in the first round, the axles bent upward, which in turn jammed them, in turn burning out the motors. We were able to repair this for the most part, but we only had one spare drive motor. Faced with being required to be in the second round to receive reimbursement for part of our expenses, we replaced one of the motors, and spent the entire round spinning in circles, because that was all we could really do.
- We should have had a mechanical engineer on the project. We did pretty well for not having one; but had we had one, our robot may have actually accomplished something.
- Gaining access to the parallel port of a computer running Windows 2000 is non-trivial. Unprivileged programs in general do not have access.
- Don't plug something in to your computer unless you're REALLY sure you wired it right (we fried one laptop's parallel port due to a incorrectly wired connector).
- Building a robot is quite fun. It would have been more fun if it worked.
- Sometimes the simple option which doesn't do 100% of what it could possible do is the better solution. Had we tried to go for something more complex (that could, say, place bocce balls on the pedestals) we likely would have never gotten it going.
- Don't be afraid to ask for a little help. We had a local car shop do an emergency weld free of charge, since our base of operations was 150 miles away from the competition, just by going in and telling them our situation.