paper: FIRST Drive Trains and Structures

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FIRST Drive Trains and Structures
by: M. Krass

_This is part of a presentation I gave at the Seattle Robotics Society meeting, Sat. Oct. 20, 2007.

It’s a very broad look at different types of FIRST drive trains and the common components that comprise them._

This presentation was made to area FIRST teams at the Seattle Robotics Society meeting, Oct. 20, 2007.

It’s a series of slides that broadly describe drive train options for teams while comparing some of the best and worst features of each – in addition to talking more specifically about certain drive components and their own functions and pitfalls.

Some folks have asked that I make it available for download, so here it is. :slight_smile:

FIRST Drive Trains_CD.zip (1.96 MB)

I am interested in this topic for research on our next years robot but there are no files to download. Do you think there is a way that I could receive these files? Thank you for your time.

I’m working on it. :slight_smile: The presentation is a just bit too big to upload here on CD, so I’m working on other options for hosting it as well as trimming out some of the photos or something.

Okay, it’s up there now – I got rid of the last, exceptionally pointless slide and voila. :slight_smile:

It really is a very straightforward presentation that was supported by a lot of discussion, so I’m not sure how well that information will translate to the website here.

I’d be happy to answer any questions anyone might have, however.

I like it a lot!! I made a power point for my team at the end of last year similar to this. only I had just info on drive trains (nothing on gearboxes or how to build it or anything like that). I may have to use this as a compliment to mine (of course if your ok with that). We have a lot of the same info on the drive trains too which means I did a good job researching lol :smiley:

I must say this is a pretty solid presentation, you cover what you need to over, have great visuals and keep it simple. Not only that but you worked humor in too it, so you can’t beat that. Thanks Madison for taking your time to do this, I am sure it will be useful for many teams.

-Drew

This is a great presentation. I may be using some of it at the next mechanical meeting after we’re done with Inventor. It’s great to have all of the bases (literally, lol) covered in one simple source.

good job. i think that that pretty much covers everything we need to teach the rookies, and heck, the professionals, too. i like how you kept it realistic…some papers are more for experienced teams and of no use to new teams. good job!

Thanks. The presentation was very good and covered everything we wanted to hear about. If there was only a way to capture everything you said as well… we maybe building a simple practice chassis in Dec.

Is that 2" C-channel for the 488 Drive Train? What do you guys use to make the holes, a mill or water jet?

I think the cad was channel, but we ended up using 1x3" tube. We cut it with a plasma cutter. It worked alright - there was a lot of cleaning involved after the pieces came out. We generally mill all of that kind of stuff now.

My favorite quote is about the banebots 56mm gearbox…

“I wouldn’t trust them farther than I can throw them”. (or words to that effect)

You know… you can get quite a bit of distance hurling one of those little things.

I’ve actually found ours to be quite reliable since they were fixed… but would have been willing to provide data on how far they could be thrown in about the first or second week of last February.

Since then they have contributed to our most reliable drivetrain ever, since their long shaft allowed for direct drive we had no chains to come off, thus eliminating one of the most common modes of failure for a drivetrain.

It is a nice powerpoint, I suspect it was a pretty fun presentation.

Thanks,

Jason

This is a great pp!

But I would say that maccanum is almost as bad a system for frc as 2 wheels (for the exact same reasons that you gave for 2 wheel systems being bad).

Fred Sayre:

Worst drivetrain in FIRST history eh? You obviously arn’t acquainted with frc100’s 2005 drivetrain (actually the whole robot was terrible :] )

We tried to build a swerve drive that year:
-we literally glued the gears into the transmissions
-the flanged bearings were put in backwards so that they immediately fell out!
-Once the gears came loose we used bent nails to keep them in!
-And then the gears stripped themselves into perfect circles!
-We used ropes instead of chains (I’m not joking)!
-Oh yes! And it scored 1 tetra all season!

Well that’s all behind us now. We’ve learned a lot from our failures, and I owe our greatest achievements to our lowest mistakes :smiley:

The folks we were presenting to were sure to heckle us for our unending dislike of the Banebots transmissions and we softened up on them a little in the end. :slight_smile: Our experience with their 256:1 transmissions was not positive, however.

Thanks, everyone, for the kind words about this presentation. I’m glad to see that folks found it helpful and we’ll be fine tuning it as Fred and I go on a world tour, apparently, and give this presentation a few more times.

well, I’m really glad i found this!
have to give a presentation in about an hour… and had forgotten about this fact.

one thing i wish i knew:

0"<X<_"

drawing a blank here…

i’ll just turn it into a math joke or something XD

Thanks,
Mason

I just meant that as a quick way of describing that teams frequently lower their center wheel <1/4" on most 6WD systems is all. Nothing fancy.

Let me know how things go if you use this presentation :slight_smile:

Yeah, I agree.
This presentation rocks! :slight_smile:
M. Krass, is it alright if we (108) use your presentation for our kids at a meeting?
Pwease? :smiley:

Wow! I just Dl’d this, and I’ve gotta give major props! This is quite the sweet little overview! I might have to yoink this for giving to my noobs… er. Freshmen?

Go for it :slight_smile: