998's robot
 

Enjoy;)

SWEET drivetrain!

:ahh: that is the most chains I have ever seen.
How many master links did you go through on that one?

Here is the control board that VertigoJoe and P.Diddy made

What's it weigh?

Greg

129 or so pounds..

That's a lot of chain! :eek:
Looks too complex for me.

Swirve?
 

Is that a 4 wheel turn drive system, or as we called it last year, swirve drive?

Egad.... That must be 1,000 links or more

thats not just overkill, thats super over kill

i have to admit, its pretty hardcore and awesome.

i envy your chains

but i can think of 10 ways that system couldve been done easier.


good luck making it useful.

Unwanted Opinions
 

Well I don't remember asking you for 10 ways it could be done easier. Why don't you just worry about your own robot.

Oh and yes it is a four wheel steering system, also a four wheel drive system.

D-Viddy: You post came off a bit harsh..

and as to soezgg: "good luck making it useful."

If it works how they want it to, and they have weight for their other mechanism(s), then it's useful and they've done it. They don't need luck any further.

Nice job, 998

and some people cant take a compliment.

That's a cool omnidirectional drive system. How much power/speed do you have?

What motors are you using to drive it with?

Looks like both drill motors (with transmissions) and both CIMs. The CIMS are sorta tough to see, but they're there in the front of the bot.

WOW! That is one impressive drivetrain...good luck at comps!

Re: Unwanted Opinions
 

AH, I found that a bit rude towards my teammate. He was giving constructive criticism and a compliment to you. Your return was a hostile remark. Well, if you really wanna do that, maybe people in your team should spend less time with chain and read this so you don't clog up one page of posts with high res pics:

Ah yes, that IS on the announcement page and I pointed it out for Team 68 too. The gallery is there for a purpose. You can't argue with me on this.

Oh yeah, and we don't worry about our robot because we finished 5 days early; had time to do a demo for our favorite sponsor and also have around 30+ hours of driver practice (2 teams each).

Nice robot. You guys did a great job.

Also, the best way to deal with immature posts like the one above is to ignore them.

Good Work and that drive system very interesting

Team 998: Do you guys have any movies of this bot in action, i'd be very interested to see.

monsieurcoffee: I'm really impressed that you have read and memorized every rule and every post on chiefdelphi.com. My hat's off to you. The sad thing is that you two little webmasters are probably the people not actually allowed to touch the robot. So they sit you on the computer and tell you to watch this site. SAD! So why don't you just go color your hair and put on your black clothes and make yourself comfortable.

If you don't like my hi-res pictures then why don't you write an e-mail to the makers and tell them how I'm killing your bandwidth. Get them to move it.

Shoulda used cable not chain. You could've had tons of extra wieght to use, chain and sprockets are heavy.

I think we considered that, but there is an ungodly about of touque required to turn all 8 wheels. We use two globe motors for the job. We were using smaller chain but it kept breaking. So we had to up all the sprocket and chain sizes.

wow.. that is one cool bot...

are u any bit worried about a bin falling on that and knocking out any of those chains tho?

or is there something covering the whole bot?

There will be wires stung across the top of the bot. Hopfully that will keep the boxes out.

Theres no need to be so hostile people. There arent that many rules, most are common sense, there are only 3 or 4 others.

If you are talking about CD's webmasters, I pity your lack of knowlegde.

If you are talking about 639, if ya look, monsiercoffee is their driver. I highly doubt that he isnt allowed to touch the robot.

The rules about not posting a bunch of images in your post, but instead linking to them is so things load faster. Its not just some dumb rule, its to help everyone out.

As a general note to everyone: cant we all just comment on the good things about peoples robots? Theres no need to criticize them about their design. You don't want people telling you how bad your robot is designed do you?

Cory

The chain is sweet.

If you're underweight, chain weight shouldn't be a concern, to me. Criticizing you for using chain is about the same as criticizing you for not being able to stack 100 boxes; it's just plain silly. Be proud of your machine, it looks great to me.

For any doubters, it's worked in the past. Maybe not perfect, but a similar system was used by ChiefDelphi (chain for translation) in '99 and a very similar system was used by 190 (chain for translation and driven off bevel gears) in '00. I'm not a fan of chain for power transmission (we're all spur gears this year), but that's the best way to do a four wheel, mechanically linked swerve in my mind. Especially considering all the traction on those double wheels. Like I said, looks sweet. I hope I get a chance to see it in action sometime. Which competitions will you be at?

Frankly, I don't blame teams for being hostile with all the negative posts lately.
For the sake of your team, please try to keep a cool head, but the nitpicking is entirely out of hand.
You can only judge a robot so much from half-finished pictures and never seeing it actually move. Try not to let the negative comments get you down. Only you guys know the real capabilities of your machine. Last year we introduced the first holonomic drive used in a FIRST competition and half the comments we got were "your traction isn't any good". Well, we proved that wrong by winning an important defensive match (something our bot was never designed for) against a machine with seemingly better traction and power.

Good luck and I'd love to see video.

Adam

coffee.. he followed the rules. He doesn't HAVE to post them to the gallery. He referenced them with IMG tags. He's wasting (if you can call it that) his, or his team's, bandwidth not ChiefDelphi's. Apache is handling the requests, not SQL.

There's too much whining lately.. we need a hug forum

all i can say is wow....impressively complex drive system...kudos to you.

Very nice. I couldn't tell from the pics but is there any device in the wheels that act as tiny differentials to help them turn?

About the arguements here. I've been known to be harsh and sarcastic to people in the past so I don't have a problem with that. However when it comes to the pics, CD has asked a number of times to post pics in the galleries only and to link them here.

Wow. Very very nice...complicated but if it works then my hats off to you....
WBI tried crab(swirve) drive 2 years in a row and we got it working pretty well in our first attempt then had a whole heap of problems with our second...

When it works its amazing...when it doesn't its the most frustrating and hard to drive system i can think of.

Great looking bot!


One question: It would appear you have to reach under the chain to shut off your bot...isn't this a bit dangerous?

What do the pneumatics on the bottom do?

you should have used electromagnets operated by a nuetrino drive powered by cold fusion. Silly mortals using chain :p

Great job. Just tensioning all of that chain is a feat in itself

btw... how did you tension all of that chain?

i still say an antigravity device would be the best way to stack things!

I gotta say I like the implementation. We tried (and failed) to do this last year. You obviously did it right from the start.

As for bins popping chains off. I doubt it. The tension should hold them on just fine.

I would like to also chime in for any video. I like watching these things move.

See you in Seattle

I can only picture what happens when you find a spare master link under the robot...

Nice job, how did you turn the power to run a horizontal shaft since all the sprockets make it vertical? We tried bevel gears last year but they just got munched so badly...

I don't know what to think about drive systems like this, 217's this season , and 360's last season. While it's really easy to make this change this to act like what I would call a "true swerve", a la Wildstang 2002 (1 drive motor per wheel, and a minimum of 2 independently rotated module systems), and even easier to integrate a gear switching mechanism (Which I believe would be the first swerve to switch gears in the history of FIRST. I don't know if 217 is switching gears in their assemblies this year.), it has a draw back that keeps me away from this type of system. If you want to rotate the direction of the wheels, and not move the drive wheels you have to drive the wheel itself to cancel out any rotation of the vertical module shaft with respect to the vertical wheel shaft. This sucks, but I guess you could take care of this in programming. I would rather avoid that if at all possible. It'd make our programmers' lives a lot easier.

But yes... Kudos to 998 for being the first Alaskans to implement a variation on the swerve drive system. I hope it works well for you. Good luck this year! :)

So now that the comps are over, how did this swerve drive work out for you guys?

Cory

Both this year and last team 247 had a 3 wheel swerve-style drive with Shifting. Last year, shifting the drills via servo, this year shifting the Drill and CIM's respective gearboxes with pnuematics.

I'm a fan of that bot. And really, its not that much chain. There are only three loops of it. So only three master links, pretty easy to find and fix.

I mean, they used chain, and chain is heavy, but the obviously minamized the amount they need and then went to great lengths to make sure that there is no way its going to fall off (except on the off chance of a bin to the middle of a long stretch as its moving . . .)

Really, I mean, they are using less chain than a lot of teams did, the only thing is that it is all on top. I bet that thing can do some crazy maneuvers.

I love it.