Purchase/Prebuild - What's the difference?

[Marc P.]

I've been watching these discussions for a while, and it seems the biggest argument seems to be where to draw the line. Should team X be able to buy a complete arm mechanism from team Y? Should just the parts and plans be for sale, or a fully functional assembly? I think that's the root of the matter, and sort of questions the role of FIRST in general- is it about the robots, or the inspiration? Yes, you can be inspired by a robot built of premade parts, and yes, you can be inspired by building the robot yourself.

Personally, I'm inspired by getting aluminum dust and shavings stuck to my hands with tap magic while milling out the mounts for our drill motors, or chopping some extruded aluminum to piece together into an arm. That doesn't mean I can't be inspired by other things or in other ways too. I think if you can make a part in house for similar/less cost, in a reasonable time period, do it. That's not to say other parts can't be purchased, but in my opinion, the line should be drawn at functionality. I don't think anyone can honestly expect teams to fabricate their own motors, so we buy them. Same goes for chain, pneumatics, etc. etc. Similarly, if there's a certain mount you designed but can't fabricate because you don't have CNC, or a good enough mill, or a lathe, or whatever, you can send the order out to a machine shop, and purchase that part. Again, the same goes for sprockets, gears, etc. Even certain advanced mechanisms, e.g. the dewalt transmission can be purchased- because it's technically a raw material. The transmission by itself is not good for much until it's changed and tweaked to work with a particular setup.

Where I draw the line is at complete bolt-on assemblies. Team X has a fool proof hanging mechanism with a 99.9% successful hang rate. It's for sale at $150. It needs a 4" by 8" footprint to bolt on to the chasis, and plug in cables 1 and 2 into pwms 7 and 8 on the RC respectively, and copy these lines of C into your code. I think that's wrong. For one thing, it's not fair to the teams who did design/build/test their own mechanisms, and if everyone purchased it, what challange would there be if everyone has the same capability to hang? If it were sold as a kit, I'd say that's better, but still has the same fairness implications. There would be more inspiration and thought in building it, but even then it would be the same as building a pre-designed lego kit (which by no means I'm saying isn't fun, just not the same as building from scratch). Now, if team X made avaliable a whitepaper describing the functions of how and why the hanger works, that's the best solution. Teams can take that and change/tweak it to their bots, perhaps purchasing individual components from team X, and asking advice in assembly. Just like is done with gearboxes now, ideas can be taken and changed to suit a particular purpose. I know we've seen a number of modified technokat geargoxes, and will probably see a lot of Whos C Tek gearboxes next year. But a complete bolt-on assembly just seems like a waste of thinking power. I know many teams don't have the resources or technology to build certain complex features, but half the fun is figuring out ways around limitations- using tools in unconventional ways to get extraordinary results- which, to me, is the ultimate form of inspiration.