Bouncing turns

[bob1million]

We just had our first practice with our bot running and when we try to turn it it bounces out of control. It is four wheel drive and we used the wheels that came with the kit.
Is there anyway to stop it from bouncing and make it turn smooth?

[dman9385]

Originally Posted by bob1million

We just had our first practice with our bot running and when we try to turn it it bounces out of control. It is four wheel drive and we used the wheels that came with the kit.
Is there anyway to stop it from bouncing and make it turn smooth?

I am currently working with 406 and we had the same problem. In order to fix that problem we found that replacing the front tires with some that have a smooth surface will give you a nice smooth turn.

[Kevin Watson]

Originally Posted by bob1million

We just had our first practice with our bot running and when we try to turn it it bounces out of control. It is four wheel drive and we used the wheels that came with the kit.
Is there anyway to stop it from bouncing and make it turn smooth?

Try increasing the tire pressure.

-Kevin

[David66]

A few weeks ago we had the same problem. It is caused by friction with the carpet. If you place the robot on a tile surface and drive it you will find that the bouncing does not occur. We were not able to find a way to negate this bouncing with the pnuematic tires, but rather went to a wheel with a low friction surface and it works great. If you have any other questions fell free to IM me on AIM: DavidButzin If I can't answer questions you have chances are I will be able to direct you to someone who can. Hope this is helpful!

[ngreen]

Last year we put casters on pneumatic cyclinder on back to lift the back wheels barely off the ground. This year we fully inflate the tires and just deal with it. There are several good solution to this including completely inflating tires and changing a set of tires so that they will slide sideways but still drive forward. Omni-wheels of sorts (not really, unless you can make them quick) But something that has less contact with the ground but still can grip forwards.

[SarahB]

Originally Posted by bob1million

We just had our first practice with our bot running and when we try to turn it it bounces out of control. It is four wheel drive and we used the wheels that came with the kit.
Is there anyway to stop it from bouncing and make it turn smooth?

It sounds like you're having the ever popular trouble with 4 wheel drive turning. Chris Hibner wrote a really good white paper to help solve this problem. If none of the quick tips here work, I'm sure some of the information in this white paper will help.

[Aignam]

Originally Posted by SarahB

It sounds like you're having the ever popular trouble with 4 wheel drive turning. Chris Hibner wrote a really good white paper to help solve this problem. If none of the quick tips here work, I'm sure some of the information in this white paper will help.

That white paper doesn't appear to be available at the moment.

[Jones571]

This was a problem at the UTC scrimmage 716 was bouncing out of control they didn't have the problem as bad after taking most of the air pressure out of there tires. Increasing the pressure made it bounce higher. even though really hard to control it looks rather amusing

[Arefin Bari]

Originally Posted by Kevin Watson

Try increasing the tire pressure.

-Kevin

just like he pointed out.... get more pressure on your tire... about 35 psi.

[jacob_dilles]

there IS another option... shave down the wheels!! or mabye get some teflon and start wraping them...

[Kevin Karan]

Yea, we noticed this problem back in week 2 durring our first trial run, we fixed it by putting casters on pnumatic cylinders. On carpet we are always in caster mode but when we climb or we are on the platform we are on awd mode.

[Elgin Clock]

Originally Posted by jacob_dilles

there IS another option... shave down the wheels!! or mabye get some teflon and start wraping them...

You can't very well shave down pneumatic wheels now can you?

[Sachiel7]

Well, at the DC Scrimmage last Saturday, I saw quite alot of bots w/ this problem...
Luckily ours wasnt one...
But anyway, the 12" pneumatics wheels seem to be used ALOT this year. Mainly, I would assume to climb the platform from the side, which based on last weekends results, isnt going to work quite as well as people would hope...
We personally stick with our 8x2" wheels, spaced out 26" wide (roughly)
I'm not too sure how to eliminate the issue. If you're not planning on going up the platform, try to get some smaller wheels with a little less traction. Or, you could make 2 big omni wheels for the front or back 2 tires of your bot using a bunch of smaller omnis.
I would make sure your tire pressure is full though. That was an issue with a few of the 12" 4x4 bots...

[blindguyinanorg]

someone posted earlier that they painted the back wheels with poly somthing or another. the robot will rotate around the front wheels because the back ones slip.


also with the tire pressure deflate the front ones and inflate the back ones. you want it to rotate around one wheel set and slide the other.

we just stuck some casters on the back that come up when we are climbing the platform

[Elgin Clock]

Somoene actually suggested using a wax type substance like armor-all on the tires? Would that work, or be legal?