Drive Belt vs. Chains

[SPFDEXP]

So our team is discussing using a drive belt instead of chains for our chasis. I want to know peoples opinion regarding using belts? Has anyone used a drive belt on thier robot? And how did it work out for you? Would you reccomend a drive belt? Id love to see some drawings or pictures of robots with drive belts whether its a new or old robot.

[Mk.32]

The kit frame is belt driven this year.
And we are doing a belt drive WCD, using Gt2 9mm belts and custom machind pulleys.

I know 973 did a pretty slick off season belt drive and I believe 11 MORT has been doing it for awhile to. They work great if you can design it properly.

[SPFDEXP]

Ok thanks. Do you have any experience with them? Do you know how reliable they are and if they're better than the chains from previous years? We have never used belts and we need as much information regarding belts.

[pmangels17]

If you don't know much about belts, it would probably be better to use chain, since they can be daunting. We haven't had many problems with either, though. The important part is that in either case, you make sure to include some way to adjust tension.

[SPFDEXP]

Originally Posted by pmangels17

If you don't know much about belts, it would probably be better to use chain, since they can be daunting. We haven't had many problems with either, though. The important part is that in either case, you make sure to include some way to adjust tension.

The reason we're looking at belts is to cut down on weight for climbing. Do you have any pictures of your drivetrain with belts?

[EricDrost]

Originally Posted by Mk.32

I believe 11 MORT has been doing it for awhile to. They work great if you can design it properly.

We've had a lot of success with using belts in the drive system. It does not provide any more efficiency than chain, but it just makes the drive a bit cleaner. If you space them correctly, they'll never break and rarely slip. We've gone through 5 event seasons with no upkeep necessary.

If you have any questions, feel free to PM me!

[Darth Drew]

My team had a bad experience with chains 3 years ago. Our frame was to flexible and the chains would frequently come off of one or both sides of the drive train so either way, make sure your frame is durable and stiff enough to prevent this from happening.

[F22Rapture]

Originally Posted by EricDrost

It does not provide any more efficiency than chain, but it just makes the drive a bit cleaner.

Not quite true, but the efficiency difference isn't so great as to be considered over other factors such as weight or complexity.

http://www.chiefdelphi.com/media/papers/2246

•Belt drive is 3% to 4% more efficient than chain.
•Belt was 6% faster to set distance from stop
•Belt traveled 8% farther for given power input
•Belt was 14% faster in speed test after initial acceleration

[Chris is me]

It's week 2 of build season. If you don't have experience with belts yet, don't do it.

All the advantages in the world aren't worth a drivetrain with mechanical problems.

If you are so close on weight that you are changing from chain to belt to make room for hanging... There's got to be weight you can remove elsewhere.

[MichaelBick]

Originally Posted by Mk.32

The kit frame is belt driven this year.
And we are doing a belt drive WCD, using Gt2 9mm belts and custom machind pulleys.

I know 973 did a pretty slick off season belt drive and I believe 11 MORT has been doing it for awhile to. They work great if you can design it properly.

You can't do belt with a WCD if you are doing an internal cross member. With an internal cross member it is impossible to get the build in/out without dis-assembly of the frame. That said, that's an easy thing to get around(cross member over the rails/no cross member).

[Mugurussa675]

If you don't have any experience with belts then use chain. However if you have experience with belts or know someone who has experience using belts, use belting. I only say use belting because its significantly lighter then chain, and to some aspects easier to use. Such as you don't have to deal with breaking the chain and re-attaching together.

[karomata]

My team has had many bad experiences with belts, so we tend to stick with chain. In 2011, we had belts drive our tube manipulator, and the belts would slip and it would render it ineffective. Chains rarely slip, normally they just snap or break, but its much harder to get a chain to malfunction than it is to get a belt to malfunction.

[pmangels17]

http://www.youtube.com/watch?v=MgYnw...XrOpK1&index=2
This is a great resource to see an effective way of running power transmission in a WCD, or any other base style, for that matter.

[Chris is me]

Originally Posted by pmangels17

http://www.youtube.com/watch?v=MgYnw...XrOpK1&index=2
This is a great resource to see an effective way of running power transmission in a WCD, or any other base style, for that matter.

If you haven't figured out a drive design by now I would definitely not do something so complicated. The design is quite complex and can easily be hard to maintain.

[pmangels17]

Originally Posted by Chris is me

If you haven't figured out a drive design by now I would definitely not do something so complicated. The design is quite complex and can easily be hard to maintain.

That is also true, and I should have mentioned it. A simple, robust drivetrain goes a long way in FRC, and more complex designs need time to be developed.