Two years ago my high school teacher informed me of two local "Robot Sumo" contests in which high school students build 15 pound robots that compete against each other on a yearly basis. I have competed in two of the competitions since then and I have placed 3rd place both times due to electrical burn-outs. I hope to do better with this robot that will be documented over a two week period before I compete with it on the 24th of this month.
Here is the current POP stage of this robot, I have built this "test" set up with lexan but I will be remaking it with hoged out 1/4" alluminum to make it more stiff. This robot will have a 4 bar lifting arm similar to Biohazard, but it will be powered by a geared down motor rather than a linier actuator. Here is the gear motor that will power it.
The motor I'm using to power the lifter is from a 14.4 volt Makita skill saw that I have geared down another 60:1 to bring the final output speed to .25 rpms, in other words it will takeone second for the 4 bar lifter arm to go its full stroke. Here is a close up of the worm gear box and the POT used for position control. Here is a shot of the motor and electronics, I took the two relays off of a Team Delta board (that lost its other electronics in a verry sad short that happend) any way I drove these two relays with the guts from a servo and two diodes. with this I was able to make a crude servo amplifier of some sorts and so far the testing I have done has been promising!
I decided that since the robot sumo will take place on a smooth surface that traction is going to play a big role in winning this contest. Here is one of the tank treads I will be using. These are from a Fast Traxx race car made by tyco.
Here are a few shots of the test drive set up. I made the bulk heads from lexan to test fit everything and so I could actually run the components to see if they are all working OK. The Sumo contest I'm entering has some rules on size limits so this robot will have to fit in an 18" cube, and it HAS to be driven by two coordless screw drivers-I guess they want every one to be even as far as motors go. Any way here is my setup, the drive wheels for the tracks are supported on both sides by 1/4" ball bearings to give it a nice smooth roll. This is as far as I am so far, look for more updates over the next few weeks!