Pros and Cons of Pneumatic Wheels?

[Duke461]

I apologize in advance if a thread has already covered this, but there are a ton of new threads out there, and a search did not bring up any results.
My basic question is:
What are all the problems and benefits of using Pneumatic Wheels?
This is meant for all aspects of the game. Driving, maneuvering, driving over the ridge in the middle (esp. that), etc.

Thank you!
-Duke

[Brian Ha]

While our team did not use them, we had the pleasure of practicing against 469 who used these wheels. They were impossible to push, even when we had grippy wheels and loe gear going. That said, our head mentor mentioned the other day that those kinds of wheels were investigated by "andymark" (i put quotations because im not sure who it was buy im pretty sure andymark did it) and they said that if u deaired them just a little then tjey would get more traction than orange grippy wheels. Also I might aswell pass on this information, our team said that if u do use those wheels slighty deflated, they will work beautifully for the bump.

Anyways sorry for the block of text.

You can get a lot more traction and speed with them, but if you aren't using a Swerve drive, it'll be hard to turn. There are also no pneumatic wheels with 'special' characteristics, e.g. mecanum, omni. My team is using Mecanums this year, hoping for better mobility.

[Duke461]

Originally Posted by ThaineP

You can get a lot more traction and speed with them, but if you aren't using a Swerve drive, it'll be hard to turn. There are also no pneumatic wheels with 'special' characteristics, e.g. mecanum, omni. My team is using Mecanums this year, hoping for better mobility.

Do you know of anyone that's ever tried a combination of pneumatics and some other wheel such as an omni? Do you think that that would work at all?

[Basel A]

Off the top of my head:

Pros:
Generally High traction (More pushing power if you've got enough torque)
Compressible (almost a built-in suspension)

Cons:
Generally High Traction (turning is harder, would have more trouble getting traction-limited)
Compressible (could mitigate a center wheel drop)

[Frenchie461]

Originally Posted by Duke461

Do you know of anyone that's ever tried a combination of pneumatics and some other wheel such as an omni? Do you think that that would work at all?

http://www.chiefdelphi.com/media/photos/35118

Seemed to work really well for these guys

[nnfuller]

Originally Posted by Basel A

Off the top of my head:
Cons:
Generally High Traction (turning is harder, would have more trouble getting traction-limited)
Compressible (could mitigate a center wheel drop)

Not if you vary pressure in your wheels. If the center wheel is stiff but the outside two are at slightly lower pressure you could effectively increase the driving radius of the one wheel

[MrForbes]

I seem to recall that 330 has also built 6 wheel drive robots with the center wheels pneumatic, and the end wheels solid. They could adjust air pressure to vary how easily the robot turns, as it also changes the "drop" of the center wheel relative to the end wheels.



(just look at the wheels on this picture)

Originally Posted by Duke461

Do you know of anyone that's ever tried a combination of pneumatics and some other wheel such as an omni? Do you think that that would work at all?

You could try a 6wd with straight omnis on the front and back and pneumatics in the center, that would be pretty fast with a turn center in the middle of the bot.

[Duke461]

Originally Posted by ThaineP

You could try a 6wd with straight omnis on the front and back and pneumatics in the center, that would be pretty fast with a turn center in the middle of the bot.

And if there were two pneumatics in the front? How would the turning be?
Thanks,
-duke

[Alex.q]

Would pneumatic wheels work in a 6wd setup if we dropped the center? I saw someone else who had trouble turning with a off-season chassis, but don't remember how the wheels were configured. There was also talk that the tires could compress and negate the center drop, so could we just drop the wheels slightly more?

If 6 pneumatics wheels wont turn well, what about a 6wd with an 1/8" dropped 8in plaction in the middle?

Thanks,
Alex

[BASE]

What do you guys think about a 6WD with 4 outside pneumatic wheels and 2 8" omni wheels in the centre? Is it cause it'll negate the whole point of dropping the centre wheels? This ideas really been floating around with me because I don't want our team to have to rely on the bridges, that could cause for some hectic traffic. You think that'll help the whole turning issue with just pneumatic wheels?

This is actually my first post, so if it's a stupid question I understand

[Tom Line]

Originally Posted by ThaineP

You can get a lot more traction and speed with them, but if you aren't using a Swerve drive, it'll be hard to turn. There are also no pneumatic wheels with 'special' characteristics, e.g. mecanum, omni. My team is using Mecanums this year, hoping for better mobility.

Can you please explain how these wheels would achieve more speed out of any particular motor?

In addition, the pneumatic wheels supposed improvement in traction is merely a result of increased contact with the floor. Because traction treads do not act ideally (they intermesh with the carpet), there is more to the story than simple normal force.

You can achieve the same amount of traction by using wider wheels to match the pneumatic's contact area.

469 did not use a swerve drive last year or the year before, and they were fairly successful at turning.