Robot Sumo

I accompanied Iris' robotics class to the First Lego League Spring Showdown 2011 at Legoland in March. Her school sent four teams, one comprised of all girls.

Part of the competition involves running an obstacle course aka mission on the main stage. The first mission is announced two months in advance so that the kids can program the robots and practice at home. The cameras trained on the tables are used to project the action on the large screens behind them. I wonder if it makes the kids feel like rock stars?

Later, the kids are given an hour to program an "on the spot" mission. That tests the kids' abilities to think algorithmically and execute their vision quickly. It also helps judges determine if the kids or their team mentors did the programming for the pre-announced mission.

In order to leave the kids alone, the coaches were all pulled into another room for the coaches' challenge: robot sumo. Iris wasn't around to help me program the Bot, but the other members of my team were very capable.

We agreed that our bot should be small, with a low center of gravity. We wanted a scooper in the front that would slide under the other bots and then tap repeatedly.

The kit has 3 motors. The first motor went on the sensor, which looked for the nearest object (hopefully, the combatant bot). The second motor moves the bot toward the object at full speed, which we hope will slide the scoop underneath the other bot. The third motor does the tapping.
We won the first match because the algorithm of our first competitor (not shown) moved their bot out of the ring with no interference from ours.

Our second competitor looked so large and formidable next to our little bot. But, he first two matches against this bot were a draw.
The way the two bots were designed, it would always be a draw if they both started in opposite ends of the oval from a dead stop. In order to introduce a little bit of variability into the initial conditions (encourage the butterfly effect), the judges had the competitors run to the table and drop the bots quickly.

Here's what happened next. Our bot is the one that started on the left.


See another time when parents were separated from children in Lego class--to the benefit of all.