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Unread 10-12-2012, 14:24
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JVN JVN is offline
@JohnVNeun
AKA: John Vielkind-Neun
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Re: VEX Robotics Relaunches VEXpro Product Line with over 120 New & Improved Products

Quote:
Originally Posted by Kevin Kolodziej View Post
I think others and you have fleshed out most of the ideas behind this, but I do still have a few questions about longevity of the mecanum wheels. Are the rollers molded directly to the axle? What material is that axle? I expect it will be able to handle normal driving conditions just fine but what about after 3 or 4 competitions...can rollers be replaced? More importantly, can an axle be replaced if it is bent? The body and spokes of the wheel does not concern me at all. We've had bent and bound rollers before but they were easily replaced.
Hi Kevin,
The axle is 5mm #45 steel. If you check out the CAD model, you can see how the axle is supported much further out than you might expect due to some creative design of the cast aluminum roller support; the bending moment on these axles is greatly reduced. We experimented with this geometry when designing the Mecanum Wheels for the VEX Robotics Design System, and liked it so much we carried it forward to the VEXpro line.



The rollers will be made from rubber co-molded onto a plastic shell. The shaft is knurled on each end and press-fit into two of these plastic shells. We will offer a replacement roller-assembly pack which includes some TBD quantity of roller-axle-bracket assemblies.



Yes, we expect it to handle 3-4 competitions "no problem." Yes, we will provide a mechanism to replace the rollers if you want fresh ones.

Does that answer your question somewhat? I will have quantitative load ratings for you sometime in the coming weeks.

-John

Last edited by JVN : 10-12-2012 at 15:01.
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