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-   -   New Vex Mecanum (http://www.chiefdelphi.com/forums/showthread.php?t=132977)

CalTran 03-02-2015 14:52

Re: New Vex Mecanum
 
For that VEXpro video, I thought that the regulation scoring platforms were 16 degrees and 2 inches high, not 4 inches?

Quote:

Originally Posted by 2.1.3 Scoring Platform
Each SCORING PLATFORM is 1 ft. 8 in. wide, 2 in. tall, and 15 ft. 7 in. long.


Mike Marandola 03-02-2015 15:09

Re: New Vex Mecanum
 
Quote:

Originally Posted by Dale (Post 1437738)
We've been doing a lot of fancy software development on our little Nanotube-based test robot while the competition robot is being built. We did have one roller break at the base where it interlocks with the hub. That was after maybe three hours drive time. We're hoping this is just an isolated case. This robot is about half the weight of an FRC robot and wasn't doing anything crazy at the time. It was no big deal to repair but we don't want to make a habit of it.

Were they the new 2015 wheels?

Dale 03-02-2015 15:10

Re: New Vex Mecanum
 
I assume so, just received them in early January.

Aren_Hill 03-02-2015 15:14

Re: New Vex Mecanum
 
Quote:

Originally Posted by Dale (Post 1437749)
I assume so, just received them in early January.

Was this per chance a wheel with 2 roller packs taped to it?
If so the rollers on the wheel were the old variety, while the two packs taped to the wheel were the new variety.

-Aren

Dale 03-02-2015 15:16

Re: New Vex Mecanum
 
Yes it was. Does that mean it's the older design? It would have been nice to include a note to that effect. We thought VexPro was just being their usually nice selves and including backups. I suspect many teams have just mounted the wheels as they came from the factory. Oh well, better to know now!

How can we tell the difference since we have several sets and some came with the upgraded wheels and some did not?

Grant Cox 03-02-2015 15:21

Re: New Vex Mecanum
 
Quote:

Originally Posted by CalTran (Post 1437742)
For that VEXpro video, I thought that the regulation scoring platforms were 16 degrees and 2 inches high, not 4 inches?

Oops. Uh.... chute door?

(Thanks for pointing that out. The field was correct, the video descriptions were not.)

Quote:

Originally Posted by XaulZan11 (Post 1437688)
How does this compare to the tests done last year? Or, did last year's wheels break under similar tests?

We haven't done any tests with pre-2015 rollers on a Recycle Rush field, but recommend making the switch if you still have any kicking around. The "break these" tests that Aren described above were for the 4" and 6" wheels with new rollers. This test was essentially a refined version of those, on a realistic field, with a camera rolling.

Aren_Hill 03-02-2015 15:21

Re: New Vex Mecanum
 
Quote:

Originally Posted by Dale (Post 1437752)
Yes it was. Does that mean it's the older design?

This was the transition point from old to new, we had existing inventory of the 6" wheels with old rollers on them, and rather than open each one up and replace the rollers, we attached two replacement roller packs of the new style to the product (enough to completely update the wheel).

This just gives you some more run time overall and was more productive than us scrapping the old rollers entirely.

-Aren

CalTran 03-02-2015 15:26

Re: New Vex Mecanum
 
Quote:

Originally Posted by Grant Cox (Post 1437754)
Oops. Uh.... chute door?

(Thanks for pointing that out. The field was correct, the video descriptions were not.)

Seeing VEXPro say that the platform (Although accidentally) 4 inches high gave me more of a heart attack then it should have, and I'm a 2 year alum! :yikes:

Mike Marandola 03-02-2015 15:27

Re: New Vex Mecanum
 
Quote:

Originally Posted by Dale (Post 1437752)
How can we tell the difference since we have several sets and some came with the upgraded wheels and some did not?


The new rollers are curved at the base on both sides. The old rollers were curved on one side and flat on the other.

Dale 03-02-2015 15:30

Re: New Vex Mecanum
 
Quote:

This was the transition point from old to new, we had existing inventory of the 6" wheels with old rollers on them, and rather than open each one up and replace the rollers, we attached two replacement roller packs of the new style to the product (enough to completely update the wheel).

This just gives you some more run time overall and was more productive than us scrapping the old rollers entirely.

-Aren
That's great and I would have done the same thing. I'll bet a lot of teams didn't know why they were getting extra rollers and put the wheels as-is on their robots. I hope they read this!

Sunshine 04-02-2015 07:26

Re: New Vex Mecanum
 
Hmmm. We placed two orders and received replacement rollers with each order.
Not overly excited to read this news. If I had known we were getting the old style wheels I would have not ordered. Very unhappy that there was no note with the order indicating that we could/should change rollers out to the new style. Now with less than two weeks left, I was lucky to read this thread (others will be less fortunate). This will cost us a few hours of valuable build time by pulling off wheels on two bots and trying to figure out which wheels are the new and old style, and then replacing. Not a happy customer.

Snowfire 04-02-2015 12:36

Re: New Vex Mecanum
 
Here's the picture of what VEXpro did to make their wheels stronger:

http://content.vexrobotics.com/vexpr...ed-mecanum.jpg

I think it will do just fine, but our team wants to wait one season to see how they preform, considering that we had 5 rollers fall off of one wheel during a match last year

Mike Marandola 17-02-2015 03:46

Re: New Vex Mecanum
 
Just to add some information:

Our wheels have been doing decent until this weekend when we were running them all day. They started developing serious play. We were forced to swap them out for the new rollers. It cost us a few hours but it rolls much better now. If anyone was curious about the insides of an old roller, here you go.

GilaMonsterAlex 23-03-2015 16:41

Re: New Vex Mecanum
 
Just wanted to update that our first set of VEX Mecanum (6inch) wheels have lasted through build, practice and one regional. We have an extra set, just in case, but we don't think we'll have any issues.

Monochron 23-03-2015 23:56

Re: New Vex Mecanum
 
I'll add a report from our team as well. Wheels performed fine through two Regionals and tons of time on the practice fields. After grinding against a 2x4 for a couple seconds however, one of the wheels' rollers developed a troubling wobble. The robot was up on blocks and one of those blocks was wedged against a wheel. Not really a typical use case, but damage was certainly done to it. We ran it for a while but eventually swapped it with a fresh wheel. The rollers were holding together just fine, it was just as if their mounting had loosened up a bit.


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