Lithion-Ion Batteries

[EricH]

Todd, I think I can address some of those. We'll let the third assumption slide as that's not necessarily true--the ARA donation and the BaneBots motors are good examples.

The second assumption is VITAL. If you're going to make a new technology legal, ALL TEAMS must be able to obtain it, preferably with minimal research. The easiest way to do that--and cheapest--is for FIRST to buy about 2000 sets of the item and distribute it via the KOP. Otherwise, you get the vouchers which may or may not be of any practical use. If it isn't in the KOP, it should be available from AndyMark/IFI/BaneBots/local retailers.

As far as the first assumption, YES! You do have to have characterizations! (We'll assume fairly complete, but not completely complete.) Why, you ask? How else are you going to size motors properly for the applications? Not all teams have the equipment to test the motors, or the budget to replace ones that fry during testing. Not having even an incomplete characterization can result in teams frying motors left and right--and even with an incomplete one... See Tetrix motors on minibots in 2011.


The paragraph on the reason for the rules, however, missed even the hay bales behind the target. That's not the reasoning at all. The original reason for the restrictions on the control system were so that FIRST technical staff (who are still comparatively few in number) didn't have to troubleshoot 40 different systems at a single event--and that is still a huge reason. Once IFI came along, it made life easier, as it was fairly easy to get teams a new control system every year--and teams with experience still managed to make dumb mistakes every year. The cRIO system was more powerful--and had a lot more issues the first couple years. See "limited technical staff not having to troubleshoot 40 different systems at each event"--and read the Einstein report again for how some teams, who've been using the system for years, made mistakes.

Having the control system the same is important, not because cheaper systems aren't powerful enough or tough enough, but because if you open the rules to more than one system, you introduce nightmares. FIRST recently put out documents indicating that they are looking for a new system--look at those, and see if you can come up with anything within their guidelines.


The motor system is the same way, except that it's limiting the maximum available power from motors instead of making the technical group's life easier. Same available motor pool = same available maximum power = no advantage unless you can put more motors from the pool on the robot and control them. It's been opening up a bit lately, but I think the main reason for brushless motors not being allowed is that the legal speed controllers can't handle them. But when you open up the pool of legal speed controllers, you have to make adjustments to the control system, somehow, or force the controllers to work with the system.

That's why, until the new control system comes out, I don't see brushless motors being legal, unless it's on a very limited basis (as in, the 2 motors must be Brand X, Motor Y, and each running on one ESC with BEC Model Z).

I'm not opposed to brushless, under the following conditions (legality is assumed):
--They have to work with the existing control system.
--There has to be a specific type or limited pool to draw from. (This would be opened up as teams gained more experience.)
--They have to come in either in the KOP or with an easy-to-use system to obtain them for a steep discount. Teams don't necessarily have the budget to go all-in quickly.