Pneumatic wheel drop distance?

[aphelps231]

What's the recommended drop distance for 8" pneumatic wheels on an 8 wheel drive train? I read somewhere that 1/4" is recommended, but I'm tending not to trust that source (reddit.com/r/frc... probably not the most trustworthy).

[Kenny Cheung]

We are running 8" pneumatic tires in a 6 wheel configuration and used a 1/4" center drop. We have not had much time to test with different pressures, but with all 6 wheels at ~30psi (its high, but we will be playing around with lower pressures later) we have no issues turning. There is also no issue with the robot rocking violently back and forth. You can always deflate the center or outer tires to effectively change the drop distance if you are not happy with 1/4".

[Maxwell777]

Originally Posted by Kenny Cheung

We are running 8" pneumatic tires in a 6 wheel configuration and used a 1/4" center drop. We have not had much time to test with different pressures, but with all 6 wheels at ~30psi (its high, but we will be playing around with lower pressures later) we have no issues turning. There is also no issue with the robot rocking violently back and forth. You can always deflate the center or outer tires to effectively change the drop distance if you are not happy with 1/4".

Are the wheels under the full weight of a competition robot? From what we've seen, as soon as you begin putting weight on the chassis, the wheels compress and you begin to run into the issue of scrubbing again.

[Mechvet]

Originally Posted by Maxwell777

Are the wheels under the full weight of a competition robot? From what we've seen, as soon as you begin putting weight on the chassis, the wheels compress and you begin to run into the issue of scrubbing again.

Vary the air pressure, as in make the dropped wheels higher pressure than the outer wheels.