The
Robots
There were robots from everywhere in Southeast
United States. 19 teams were the finalists in Lexington. There were a lot of original
designs made for the competition. We saw tiny quiet robots and big noisy robots that hit
without control every wall in the playfield. All of them share a powerful motor system.
This was due to the big 15 degrees hill that they had to climb. Some robots had trouble
climbing the hill, others opening the mine door and getting inside. In fact I remember one
robot that got stuck in the door because of its size.
Troubleshooting
Because we started to build the robot only 6
weeks before the competition we just had time to make the robot. We didn't have time to
make big modifications. One of the errors was to place the motor wheels behind and too
close to the gravity center. This made impossible to climb the hill in a forward direction
because the big torque of the stepper motors caused the robot making a willy loop.
Therefore, we had to change the programming to climb the hill backwards. As a result, the
ultrasonic control system that steered the robot in the climbing was not operative due to
the new inverted position of the ultrasonic sensors respect to the wheels. We did not have
time to develop a new secondary ultrasonic system to climb the hill, so we develop a IR
tracking line system to track the white line on the hill. That was made in only 4 hours, 4
days before going to Kentucky. That last week was really exciting because each hour was
important.
Another
error was the wheels choice. The wheels were made from wood and had a rubber tire. This
tire was ok in the testing that we did in Mississippi but they slipped in the real hill in
Kentucky. This was due to the different kind of surface between our playfield and the one
in the competition. The result was that we failed to climb the hill completely.
Pictures
of the Competition
We made several pictures of the
competition and the testing in lab of our robot and the other team's robot in The
University of Southern Mississippi.
