Summer Project 3 - Omni/traction wheel diameter dilemma

[msaunders]

I have submitted a request to the CAD group.

[kprzewodek]

Here's a link to our chassis drawing set. Hope this helps.

http://a360.co/11JKreu

[kprzewodek]

Tried to reply a few times and it's not going through. Now I wonder if it has something to do with the external link I attached. Here it is again with direct pdf attachment.

Hope this helps

[marccenter]

Originally Posted by kprzewodek

Hope this helps

Thanks. I'm surprised to see only 1/8 inch difference? In the interim I had a chance to measure the wedgetop tread (good 0.25 inches) and find a dimension somewhere (McMaster - 0.31 inches). I would have expected some dimension between those. With 6 inch traction wheel radius being 3.25 - 3.31 and OMNI right at 3.00, I would have expected the traction wheels to be raised to maybe 0.75 and the OMNI's at 0.50. Did you use the smoother, roughtop tread?

[msaunders]

We used the standard rough top tread from Vex.

Keep in mind that some of the rubber part of the tread fits inside the wheel edges (from the picture I see you are aware of this) and that the tread will get compressed a bit by the weight of the robot.

As I recall there were a few discussions when this dimensions was being determined.

.. I took a look at your image and it does not appear you have the tread fully seated in the rim all the way around.
Did you loosen the bolts holding the two side together, then lay in the tread and retighten the two halves together?

Where are you getting the dimension for the 6" traction wheel?
http://content.vexrobotics.com/vexpr...g-20130115.PDF

After further recall, we ended up deciding that the traction wheel with tread has a radius of 3.125 and the Omni as 3.00.