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Posted by Eric Rasmussen.

Engineer from FIRST.

Posted on 8/26/2000 8:58 PM MST


In Reply to: Since when are we not up for the challenge??? posted by colleen on 8/20/2000 9:25 PM MST:



: Think of Maize Craze.. a corn bed... i bet people thought that was 'impossible'.. couldn't happen.. was too hard.. etc... but 28 teams didn't see it as such.. heck, on my old team, they built their robot after a kid who worked on a golf course said 'hey, you know those little trucks they drive around to pick-up the golf balls.. hey maybe we could use something like that..'...when's the last time many of us had to think like that??

Note: Don't take the following as a commentary on the future of FIRST games, just a comment about the past.

I competed that year and the corn was _very_ difficult to deal with. In fact, it took us about 3 weeks and a ton of experimenting to design a good drive train. Corn gets between chains and sprockets and either wedges them or causes the chain to slip off. The same thing goes for pulleys and belts. Two-wheel drive is not an option because of the resistance of the corn. Normal and really wide wheels just sink into the corn and spin, like a car stuck in mud or snow. Wide treads have the same problems as pulleys and belts plus they make it really hard to turn. The first drive system we developed that actually worked was a set of four 'paddle wheels' that would churn through the corn like the paddles on a riverboat.

We ended up designing tall thin tires that cut through the corn to the plywood below, had rubber tubes around the perimiter for traction (tires). We powered the front wheels from the motors and the rear by a narrow, round belt in a wide grooved pulley which allowed the corn to flow around the belt without lifting it out of the groove.

Other teams that I remember: Nypro had a cool design with what appeared to be about 20 wheels on 4 axles that not only propelled the robot but also picked up the balls, and the Technocats had a really light and fast robot that ran around on top of the corn with spikey aluminum spokes that approximated the shape of wheels.

All in all, it was very satisfying to come up with something that worked well, and very interesting to see all the different designs. However, many teams struggled and never came up with a good solution. Also, the corn had to be raked into a smooth state before every match, which slowed things down.

One amusing benefit to the corn was that a Physics professor who helped on the team got to take home all the corn from our practice field once the competition was over and feed it to chickens he kept on his property.

-Eric