VersaWheel vs Traction wheels

[Ravage457]

Hello FRC community

As we are on the verge of the 2014 FRC season, I have a question for everyone. I been looking at the versawheel from vexpro and been wondering, what would yall recommend. We have been using Traction wheels since 2011, and the bad thing about them is when the wheel thread wears out you have to go and replace the thread or the wheel if you have spares with you. Now I was wondering how did the versawheel handle the abuse of multiple regionals and State/World Championships and off season events. Did the wheels last or did any of them fail.
what would everyone recommend?

[ttldomination]

If I remember correctly, someone posted a picture of the versas after a couple of regionals. All that was left of the versa treads were nubs.

With that being said, my team used traction this year, and we were as happy as could be. If you're finding that the tread is wearing too fast, perhaps considering using the nitrile material from McMaster.

- Sunny G.

[thefro526]

Originally Posted by ttldomination

If I remember correctly, someone posted a picture of the versas after a couple of regionals. All that was left of the versa treads were nubs.

You may have seem my post in this thread: http://www.chiefdelphi.com/forums/sh...06#post1257706

Originally Posted by thefro526

Sorry I'm a bit late with this reply, been a bit busy competing...

Here's a picture showing the difference in tread profile between a well-worn versawheel and a brand new one. The wheel on the left has ~40 'official' matches on it, ~10 practice matches and some build season run time on it. It's noticeably slicker than a new wheel, almost as if the tread has glazed over.

Personally, I think the Versa Wheel is the best 'bang for buck' wheel out there, with it's only real issue being tread wear. Subjectively, I'd say that they wear about as fast as gum rubber rough-top tread, but have superior traction characteristics in the fore/aft direction, while having a lower lateral COF (makes turning easier.) If you're looking for a long term wheel solution (something that doesn't wear) then blue nitrile is probably your best bet, or a colson wheel.

The trick to using Versawheels is to design the drive around them being removed at least once per event, and if your budget is friendly enough, have a complete second set of wheels (with hardware) on hand to swap for a worn set. This is what we did, and a wheel swap (6 to 8 wheels each swap) could be done in about 5 minutes.

[Chris is me]

Has anyone done a head to head comparison of VersaWheels versus Colsons? Our drivetrain is set up to make wheel swaps completely painless. If we can gain traction and lose weight in exchange for having to buy a few different sets of wheels, I think that's a worthy tradeoff. However, Colsons have proven tough to beat in terms of traction.

[MichaelBick]

Originally Posted by Chris is me

However, Colsons have proven tough to beat in terms of traction.

I'm not sure that it is true. I believe teams who have tested colsons have found that they have similar traction on carpet to 1" wide roughtop. While I don't know how this compares to versas, wider roughtop wheels(1.5" - 2") is going to give you more traction on carpet then colsons. On the other hand, colsons have much better traction on smooth surfaces(i.e. polycarb) than other wheels.

[AllenGregoryIV]

We used VersaWheels this season and really liked them. Like other teams have said they do ware but when they are new they hard to beat. The idea that they lack lateral traction is a bit more complicated I think than people are making it out. A new set of VersaWheels that still have their corners when pushed sideways (for instance in a t-bone collision) dig into the carpets like cleats. It's pretty hard to move them.

It will be interesting next season when VEXpro releases the tires for their traction wheels.

[BBray_T1296]

I am curious how a wheel would perform if you did this to it:

Take a 1.5" or 2" traction wheel
Remove the traction belt (roughtop, wedge, whatever) or just don't attach tread to a new one
Instead, stick that super sticky (tape side) Velcro tape onto the wheel in place of the tread, Hook side of course

Have unbeatable traction as your robot is constantly Velcroed to the carpet. (hopefully you have enough torque to unstick yourself!)

[nathannfm]

Originally Posted by BBray_T1296

Take a 1.5" or 2" traction wheel
Remove the traction belt (roughtop, wedge, whatever) or just don't attach tread to a new one
Instead, stick that super sticky (tape side) Velcro tape onto the wheel in place of the tread, Hook side of course

Have unbeatable traction as your robot is constantly Velcroed to the carpet. (hopefully you have enough torque to unstick yourself!)

While this would be rather intresting to see, something is going to have to give when you want to turn, and im betting it would be the sticky tape, but if you want to talk about velcro there is this legend http://www.youtube.com/watch?v=2eKvva_ZCHw

Also, on topic, just some anecdotal evidence, I have seen bots using VersaWheel that were great at head to head pushing get pushed around the field when hit from the side. They may have had worn down wheels as stated in other posts, but it is still something to consider.
My vote, from what I saw with my teams bot last year is go Colson, we were pushing people left and right. Requisite GIF http://imgur.com/4eHq8lP

[AllenGregoryIV]

Originally Posted by nathannfm

but if you want to talk about velcro there is this legend http://www.youtube.com/watch?v=2eKvva_ZCHw

Just to be clear, The Beast wasn't using velcro they were using metal file cards. Something like these. This thread has more information and for the record it is now very illegal to use metal as a traction device.

[nathannfm]

Originally Posted by AllenGregoryIV

Just to be clear, The Beast wasn't using velcro they were using metal file cards. Something like these. This thread has more information and for the record it is now very illegal to use metal as a traction device.

Ah, thanks, I was always told it was velcro.
Heh, that rule was introduced in 2003, I wonder why

[Gdeaver]

Colson does offer wider wheels up to 2" in 4" d. I like Colson wheels for traction wear and price. However it takes a bit of work to mount a sprocket on them.

[thefro526]

Originally Posted by AllenGregoryIV

We used VersaWheels this season and really liked them. Like other teams have said they do ware but when they are new they hard to beat. The idea that they lack lateral traction is a bit more complicated I think than people are making it out. A new set of VersaWheels that still have their corners when pushed sideways (for instance in a t-bone collision) dig into the carpets like cleats. It's pretty hard to move them.

It will be interesting next season when VEXpro releases the tires for their traction wheels.

The Lateral Traction of Versa Wheels probably isn't as simple as I described it in my previous post. I also observed the 'cleating' effect that you're describing, especially when being pushed from the side while not in motion or moving all that quickly. That being said, once the robot is in motion and turning, this cleating effect seems to go away almost entirely. I guess a more appropriate way to describe this would be 'scrub' or turning resistance.

Thinking about it more, the effective scrub could have a lot of do with the forces on the robot, in our case, our CoF was lower than most (with the arm down) meaning that while turning the robot stayed relatively flat but while being t-boned, there was a noticeable tipping towards one side (side being pushed would be lifted). I suspect that this tipping is a major player in the lateral characteristics of the wheel, if it stays flat it's going to have more of a tendency to 'slice' through the carpet, but if it tips you'll get a cleating effect.

[ttldomination]

Originally Posted by Gdeaver

Colson does offer wider wheels up to 2" in 4" d. I like Colson wheels for traction wear and price. However it takes a bit of work to mount a sprocket on them.

Originally Posted by nathannfm

Not any more
http://www.robotmarketplace.com/prod...WCP-00052.html

I'm curious, are colson wheels really that much better than traction wheels?

I've been using traction wheels for the better part of a decade with zero complaints. Yet, the colson wheel is often praised as the superior wheel.

- Sunny G.

[Nemo]

Does anybody have CoF data for AndyMark HiGrip wheels compared to Versawheels? We're planning to try 4" AndyMark wheels for our fall practice drive. If nobody has that data, maybe we can buy a set of each type and do some testing.

[Chris is me]

Originally Posted by ttldomination

I'm curious, are colson wheels really that much better than traction wheels?

I've been using traction wheels for the better part of a decade with zero complaints. Yet, the colson wheel is often praised as the superior wheel.

- Sunny G.

Like many things in robotics, it's not necessarily what's better, but what's better for your team / situation / strategy.

In terms of purely static CoF on carpet, roughtop wins there. If you don't mind changing tread and want the most traction possible, go for it. It's worth noting that your effective CoF can change depending on what wheel you use - for example, try measuring the CoF of a Plaction wheel vs an AM Performance.

Colsons have some specific advantages. First, in terms of FRC they basically don't wear. Maybe with 200 matches and hours of practice, with small wheels, you might have to change them once. We've used the wheels for multiple years without having to change them. Secondly, the traction is pretty good across a variety of surfaces. While roughtop might be 1.2-1.3 CoF on carpet, Colsons are pretty close at 1.1-1.2. Off carpet, Colsons maintain their high traction while roughtop can suffer a bit. This was most evident on the key and bridge in 2012. Colsons also seem to get "stickier" throughout a match as they heat up, but this is hard to quantify.

Basically, Colsons are almost as good in pure carpet games without requiring maintenance of any kind. It's a team / driver preference thing, really.