LVL1 has a small rivalry with a few of the regional hackerspaces. Back in October 2010, when we were but a fledgling space, we hosted a Sumo Bot tournament. Hive13 and Bloominglabs came by, and we kicked their butts. Hive13 held the rematch a few months ago, and I started work on my SumoBot. Unfortunately, I didn’t finish in time, but the effort itself is worthwhile, and my bot will live to see the next match.
Sumobots are robots which seek to push each other out of a small ring. The ring is black, with a white boundary circle. Two robots enter, one robot leaves. Our competitions use the Mini-Sumo class of rules, allowing for a Sumobot which can fit inside a 10cm by 10cm rectangular tube, weighing under 500 grams. I decided to print my SumoBot on our makerbot.
Thingiverse is a great website for finding models of parts to print. Unfortunately, they aren’t always well-tailored for the machine you’ve got. In this case, LVL1′s makerbot, Veruca, just couldn’t handle some of the parts from this model: SumoBot Chassis. The motor mount and the connector printed out after about a half dozen tries each (The Makerbot is not a fool-proof technology), but the scoop failed over and over again.
In the end, I just designed my own in Google Sketchup, and exported it to an STL file. This one only took two attempts to print, although the leading edge is weaker than the design from Thingiverse.
I had some motors from Solarbotics, but I got the rest of my parts from Pololu. The Baby Orangutan controller was a great choice, with a build in 2A H-Bridge, and AtMega328 microprocessor. I also got their cheapest sonar distance sensor, and some line sensors.
The board was developed in house, and includes headers for motors, sensors, and a servo. The plan is that the sonar will sit on top of a servo, and scan back and forth for enemies. This will allow for fast response to laterally moving targets.
Unfortnately, I never got beyond assembling the PCB. But some day, she will taste blood.