where can i find info on drive trains?
i have been assigned the tentative drive train captain for this year and for the past two years have usually been on the other design teams
(manipulator, ball picker upper, etc). Anyhow, i don’t know a whole lot about FIRST drivetrains although i understand torque and basic physics principles.
i just need some guidence and any tips and tricks on designing and building drive trains for a FIRST robot.
thanks alot
I believe thisis the powerpoint that JamesBrown is talking about.
Also you may find these whitepapers useful:
http://www.chiefdelphi.com/media/papers/1705
http://www.chiefdelphi.com/media/papers/1443
The gallery of photos maintained by the FIRST Robotics Canada folks is pretty helpful, too. There’s not much exposition, but looking at the pictures can show you a lot about the practicality of implementing certain ideas.
I always find the Chief Delphi white papers useful. There is a link to them on the portal page. You can search through a bunch of different transmission ideas and designs. No matter how many times you built and designed a bot in never gets old. Good Luck with your search and this coming season.
-Drew
thanks guys
If you’re looking for a superior drivetrain, I strongly suggest you look hard into the possibility of a track system. Well designed, a tracked 'bot will push anything else on the field, forward, backward, or sideways. Tracked bots can turn on their footprints, and with the right transmission can go as fast as any other bot.
753 has racked up a bit of a record on the strength of our drivetrains. Last year we won the PNW regional and went to nationals, where we took a divisional third along with 254 and 71. We did it on the strength of our drivetrain; our scorer hardly worked at all but we could guarantee to stop other bots from scoring. 254 knew it was a very strong complement to their scoring, and they drafted us in PNW and at nationals.
This year we’re pleased to partner with our sponsor, Outback Manufacturing, to make our award-winning drivetrain available to other teams. Outfitted with a 2-speed transmission, the 'train can go 17 FPS in high gear, and in low has more pushing power than last year’s bot!
Because of the lead time to do with the belts from Breco-flex, we need to know whether you’re doing it pretty soon so you can get the belts early in the season. Email me at ari.allynfeuer@gmail.com or use a forum PM to talk about it.
Ari.
First, and most important, what do you want out of it? Do you want speed, maneuverability, or power? To some extent, these three will not work together without a shifting transmission.
For speed: high gearing with any transmission/wheel pattern will work, if you do your calculations right.
For maneuverability: 2-wheel, 6-wheel with a dropped center, swerve, or mecanum are your basic options. You want to avoid using swerve and mecanum until you have explored them. Some teams make these look easy, but they aren’t.
Power: low gearing with anything, but no speed.
Tank treads: Be careful. One tread comes off, you are disabled for the rest of the match. You have to design right for treads.
Bottom line: Explore a bit. If you are a rookie, you should be somewhat conservative on complexity. After that, explore all the options you like. Do the power curves to find out what the trannies will behave like. Try shifting.
If you’re expecting teams to order now so that you’re able to provide these units “early” in the build season, you are not in compliance with the 2006 rules regarding what constitutes a vendor. The rules require that you ship your product no more than five days after receiving an order. Unless the rule changes drastically or you take measure to stock belts, teams cannot use a drive purchased from your team on a competition robot.
Can you explain more about the mechanism your team has in place to comply with FIRST’s rules defining what a vendor is?
I don’t mean to doubt anyone’s abilities but you want a rookie team to build a track system? And it will be superior? Track systems are riddled with all sorts of inherent problems, and unless there is a step to climb (which I’m actually fairly certain there will be, but we’ll see) I haven’t seen a compelling argument for the use of them.
They don’t want them to build a track system. They want them to buy it. :rolleyes:
The lead time has nothing to do with Outback. Breco-Flex, one of three official FIRST suppliers cooperating on this, has a manufacturing lead time of 3 to 4 weeks. We need to have a sense of who’s doing this so we can get the first production run from Breco-Flex in their pipeline in time to deliver the system early in the season.
These kind of delays are not an unfamiliar prospect to FIRST teams or any other intercorporate purchasing arrangement, and the rules from 2006 (And, it is safe to assume, 2007) allow for the delays inherent in this kind of thing. Would you say Breco-Flex is not a Vendor?
What we’re trying to do is simplify the insane free-for-all of custom ordering from Breco-Flex that goes on. To make it easier for Breco-Flex by using a single size, and to make it easier for the teams by reducing the lead time by keeping the tracks in stock.
Outback is an established manufacturing shop with all the requisite tax numbers, and the delays are the result of a third-party supplier which is an official FIRST supplier. We don’t anticipate any rules issues.
Thanks,
Ari.
And these systems would count as COTS parts, right? If they don’t, then you should really be gauging interest, not ordering.
I think this highlights some interesting issues that I’d like to continue discussing, so I’m going to begin a new thread in the General Forum to address those concerns so as to avoid derailing the continuing valuable discussion about drive trains.
Once again, you do not need to lower your center wheel.
everyone else needs to 
Team 2199 as of now is not interested in buying anyones drive train although we appreciate the offer and admire your entrupenuerial spirit. I was just looking for some guiding princilples and ideas. Right now (unless this years comp throws a monkey wrench in our plans) we are looking at a six wheel drive. We are a rookie team but the officers are all veterens from another team so we have have a bunch of rookies under veteren leadership.
agian, many thanks
I understand fully. It’s not a thing everyone will want to do.
I’m glad you gave it a thought, and I hope we’ll see you on the field in a few months. If you have any questions drop me a line.
Ari.
The tracks that 195 has used for the last few years have been ordered from Breco-Flex. Overall great quality, but like Eric H said, one track slips and your completely disabled from the match, we experienced alot of that in the 2006 game, which we partially attribute to the defined defensive period, in which we got pushed from angles that never quite hit us before. My main concern with Breco-Flex is that return time on ordering tracks was anywhere between 5-7 weeks, which made it pretty hectic after we snapped 8 tracks at our first regional =O