Re: WCD vs. Swerve
 

I wouldn't say they've perfected it, but 973's swerve is one of the best swerves I've seen in my days, and I've seen a lot of swerves.

Re: WCD vs. Swerve
 

Well then, I respectfully disagree.

Re: WCD vs. Swerve
 

No, they aren't.

111. 1 National Championship on swerve drive. Uses it fairly often when the game calls for it.
118. 2-3 years with what was then one of the ultimate swerve drives.
67. 1 World Championship on swerve drive.
148. See 67.
1717. Consistently uses swerve.

973 developed a Unicorn drive (Emperor Swerve) this offseason that could rival some of these others. They have yet to use it in the regular season.

16 is NOT the only team that has come close to perfecting swerve, or that consistently uses it. While they do consistently use a very good one, saying that they are the only one displays ignorance. Continuing to say that they are the only one after other teams in the same category have been brought to one's attention displays willful ignorance.

Use of swerve without proper engineering analysis to determine that it is the best option, or close to it, is a very risky proposition at best, and a waste of resources at worst.

Re: WCD vs. Swerve
 

You forgot a pretty major team that has used swerve quite a few times since their latest World Championship (my gut says every year). Though they haven't been quite the BEAST they have been in the past they still beatty out most teams for always managing to find a way to win. I speak of course of Team Hammond for those of you who hadn't figured it out.

Also, 469 used swerve for a couple years (07/08) with reasonable success.

Re: WCD vs. Swerve
 

If you look at videos of 1717, you will see how smooth and perfected their drivetrain has become. They consistently use it, and it shows, how while not being necessary, swerve helps so much in scoring. Of course, this relies on the fact that swerve is built and programmed right.

Re: WCD vs. Swerve
 

111 is swerve as far as I'm concerned.

I don't mean that as a sleight to 16, 47, 118, etc. If I think of swerve I think of 111 and then everyone else.

Re: WCD vs. Swerve
 

A lot of people posting without first hand knowledge, that's fun.

Adam and 973 are in the best position to answer the original question, as they've had quite a few 6wd cantilevered drivetrains and have recently given swerve a try.

My recommendations is know what you're getting into, easiest way to do that is have a fully functional prototype you can drive the wheels off of. I agree with Adam that the programming/control aspect is what makes a swerve great, I've seen many swerves (ours included), with control not quite what it should've been. As a result many of the Pro's were diminished and the effectiveness brought below that of a normal 6wd or 8wd in some cases.

Re: WCD vs. Swerve
 

Last year the Pigmice built a swerve drive (but like idiots we didn't prototype it in the offseason). Everything that we did worked, and we had no issues until it came to driving.
Because we hadn't prototyped it in the off season no one had ever driven it extensively. We wound up modifying it in the pits to drive like a tank (two sets of omni wheels in the front pods). This made the robot easy to drive, and because the swerve cababilities were left intact, we had fun watching people's faces when we could simply strafe around them.

Moral of the story, don't build it if you don't know how to use it to it's full potential. Our scoring during regionals would have been nearly identical if we had gone WCD.

Oh, and its cool, but very rarely necessary. If you have the time and the money, try it, but drive it into the ground in the off season before you decide to compete with it.

Re: WCD vs. Swerve
 

Excellent point.

Listen to the the EWCP podcast from November 27th where they discuss in depth what 973 went through and thought of when they built their swerve and their experience driving both. It's fun to hear people discuss their first hand account.

Now to my opinion: If you don't have a drivable fully working swerve built in the offseason (offseason is really over so I mean today) you will probably not be ready this season. If you can't drive you can't do anything. The time it will take to get the drive up and running in the build season will submarine most of the stuff you're working on. In my experience when driving is a forgone conclusion you can focus better on accomplishing the game task, scoring points. I use the kit bot as an example of this. Prior to the 2005 intro of the 1st kitbot you were very lucky if your partners could drive during quals sometimes and fewer teams could accomplish difficult tasks because the whole build season was spent getting the ability to drive. End opinion.

Re: WCD vs. Swerve
 

2 National Championships. 2003 and 2009.

Re: WCD vs. Swerve
 

1640 has done 4 wheel independent drive, independent steering the last two years. We have the weight of each module down to 9 LBS. We have the durability nailed too. Greater that 100 hours on both bots. We have put an enormous amount of time, effort and money into swerve drive. Most teams may be stressed beyond their limits to perfect a swerve drive. With swerve you basically have to have every thing perfect or things will go very bad. The risk of failure with taking on swerve would lead me to recommend that most teams forget swerve and work on perfecting a 6 wheel drive base and focus more time on other aspects of the robot. We still do not have the swerve where we want it. We need to work on the driver presentation. I will say that with this years swerve and a trained driver, swerve can be a real competitive advantage. Is it worth the effort and money. We debate this issue constantly. If you don't have a functioning swerve drive base right now then it's a no brainer, do a 6 wheel for 2012.

Re: WCD vs. Swerve
 

What is it about the driver interface that you need to work on?

Re: WCD vs. Swerve
 

Piggy-backing on what Aren said- listen to some teams who have done a swerve before, and really try to understand the effort that was put into it.

For every 16, 111 or 118, there's got to be at least a dozen failed swerve drives. I say "failed" in the sense that they did not perform at those levels. The best swerve drives have tons of iteration in them. Obviously at some point you will have to commit to putting one on the field, but now-a-days with the kit bot and the larger knowledge base, almost anyone has a strong drivetrain on the field.

We have a couple iterations of swerve drive under our belt in the off-season, but we've still yet to implement it due to a number of reasons. I wouldn't even dream of trying to conjure a swerve for the 1st time in-season. There tends to be a ton of effort that many people overlook when they make the decision to pursue one. Make sure you are making a decision based on your resources, and your abilities.

-Brando

Re: WCD vs. Swerve
 

Brandon, could you elaborate a little on some of those reasons?

Re: WCD vs. Swerve
 

Sure-

-We are probably at a spot now where mechanically we would feel comfortable with the system, however the first couple of tries definitely required some improvements before being implemented on the field.

-Part of those mechanical improvements were getting the weight down. We were at a decent spot weight wise with our initial design, but have been unable to get much more weight out of it. We're considering much different and new designs which would help with that, but then the mechanical iteration kind of goes backwards a little bit.

-Probably the biggest factor is the software development effort. We are just not at the point where the swerve is performing how we want it to. It requires a ton of driver practice to reach a level of performance that can be matched with just a small amount of practice on a 6WD or 8WD. We want to develop as intuitive a system as possible.

To go along with this, due to the nature of the mentors on our team (mainly college students), the engineering support is constantly in flux. While always solid, its ever changing. We really need someone to make this project their baby and help guide it to completion. We have unfortunately been unable to do that. Knowing it will probably take a couple of seasons to get right, we want to make sure we have a steady foundation before we start building on it.

-The last major factor has probably been timing. In 2010, we built a robot that very few teams attempted to build. Like 469, we were designed to recycle balls from the roll-in ramp by rolling them down our robot, off the bump, and into the goal. Being way to overly ambitious, we wanted to do all of this while hanging from the bar. Due to a number of reasons, the robot worked, but never as well as we wanted it to, or near the level of 469.

Going into last season we didn't want to have another "down" year, so we tried to play it "safe". If we went the swerve, and didn't get desirable results we would've had back to back seasons where our ambition got in the way of our success. We had an extremely successful year last year, so I believe the decision was right.

It is yet to be seen what will happen this upcoming season, but hopefully that gives you a window into some of our decision making.