Build Your Own Combat Robot

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HE referee signals, and my heartbeat increases as I press my bot’s start
button. I stand back to mentally count down the 5 seconds that my bot must remain
still before it can move. In my excitement, I mentally reach the 5 seconds before
my machine starts to move. I panic, thinking he must be broken, but then
both bots start moving forward. As my bot approaches his victim, I smile. The
crowd cheers... I’m thinking, “I’ve got him now!”
But the bots just pass each other as if each one is the only player in the ring, and
the crowd goes silent. My bot is now heading full-steam ahead toward the edge of
the ring, and I suddenly think, “What if the edge sensors aren’t working?!” As
soon as my machine gets to the white edge of the sumo ring, it stops, backs up a bit,
then spins around, and I breathe a sigh of relief that all seems to be working correctly.
This time, my bot is heading right for his opponent, and nothing will stop
him this time.
As my bot approaches his foe, he makes a couple of quick course corrections in
order to zero in on the enemy. I’m thrilled that my object detection sensors are
working. My bot closes in on his adversary, and the crowd starts cheering again.
Just as he’s about to hit his opponent, the rival bot suddenly turns toward mine.
The crowd cheers louder. The bots crash into each other. My breathing almost
stops as both machines halt in the center of the ring. The wheels of my bot are spinning
on the ring surface.
My robot starts pushing his challenger steadily backward. Just as I think I’ve
won the match for sure, the other bot gets better wheel traction and starts pushing
mine backward. The crowd goes wild. I bite my lower lip. Thankfully, my bot’s
traction improves and he begins pushing his foe backward. As the backward and
forward motions continue inside a one-inch area, our bots both start slipping sideways.
As soon as they come apart, they shoot toward each other again—but their
wheels get caught, and they start the classic “spinning dance.” The crowd quiets
down. This is turning out to be a much tougher battle than I’d anticipated.
The referee stops the match to separate the bots. I take a couple of deep breaths,
and we restart. This time, when my bot reaches the edge of the sumo ring and
backs up, he only turns 90 degrees. I’m glad I used a random turning method in the
software! This time my machine approaches the rear of his rival. I smile to myself,
because I can see he’s going for the vulnerable spot. The crowd goes wild. I look at
my human opponent’s face, and I can see in his eyes that he knows his bot will lose.