The Barrier Thread

[mdiradoorian]

Originally Posted by davidthefat

But you had that little thing in front. Do you think something similar will go through inspection?

It will be underneath our bumper.

[lemiant]

To everyone who thinks you can cross the bump unaided (that video shows what lifting the robot before the wheels hit can do) with 6" wheel, I'm fairly sure that is wrong. The center of your wheel is 3" off the ground and as such you would ram flat into the metal. MY guess is that you'd break the wheels or send your robot hurtling head over heels before it would go over the bump. Even a 8" wheel would be sketchy, because it is level with the top of the metal. To be certain you would need 10" wheels.

[mdiradoorian]

or you can have pneumatic wheels

[Ankit S.]

Originally Posted by mdiradoorian

or you can have pneumatic wheels

I was thinking about this too, the 8 inchers from AndyMark are lookin' especially nice right about now...

[R.C.]

Originally Posted by lemiant

To everyone who thinks you can cross the bump unaided (that video shows what lifting the robot before the wheels hit can do) with 6" wheel, I'm fairly sure that is wrong. The center of your wheel is 3" off the ground and as such you would ram flat into the metal. MY guess is that you'd break the wheels or send your robot hurtling head over heels before it would go over the bump. Even a 8" wheel would be sketchy, because it is level with the top of the metal. To be certain you would need 10" wheels.

Alex,

If you actually do the math and check your geometry, you will come to the conclusion that a 8wd 6" wheel will definitely clear the 4" "Bump". Also there are a lot of ways with 4"-6" wheels you can clear it. 10" wheels would be a bit overkill.

-RC

[Gray Adams]

Originally Posted by R.C.

Alex,

If you actually do the math and check your geometry, you will come to the conclusion that a 8wd 6" wheel will definitely clear the 4" "Bump". Also there are a lot of ways with 4"-6" wheels you can clear it. 10" wheels would be a bit overkill.

-RC

Yeah, our feeling is that just throwing more wheels at the problem would be more effective than massive wheels.

[Bill_B]

FRC gamers are so used to nice flat surfaces (for the most part) we hardly ever think of a standard vehicular feature ---- suspensions. I'm looking forward to see what the 6WD fans do for this year.

[DonRotolo]

Originally Posted by lemiant

To everyone who thinks you can cross the bump unaided <> with 6" wheel, I'm fairly sure that is wrong.

Sorry, but I have to disagree. I can even do it with 4" wheels.

As a trivial example, imagine a wooden 'ramp' at the front end of the robot (inside the bumper perimeter), starting at 5" and ending at 2". Hitting the barrier at speed will launch the bot over.
As for high-centering, if you use Gates Belt instead of chain, it can act as a tank tread for between the wheels.

[Ninja_Bait]

Originally Posted by DonRotolo

Sorry, but I have to disagree. I can even do it with 4" wheels.

As a trivial example, imagine a wooden 'ramp' at the front end of the robot (inside the bumper perimeter), starting at 5" and ending at 2". Hitting the barrier at speed will launch the bot over.
As for high-centering, if you use Gates Belt instead of chain, it can act as a tank tread for between the wheels.

Key word in the post you quoted was "unaided". Take away the wedge and try again.

[Bjenks548]

I bet our 2010 robot could make it over with no problems!
http://www.chiefdelphi.com/media/photos/35272Some nice 10in pneumatic tires!

We're planning on using the slants in front of our robot along with the 8" pneumatics from Andymark. Deflate the wheels a tiny bit, and they become instant shock absorbers.