OK, so technically not “new” anymore, but… last month, we announced new 2" Omni-Directional Wheels and an updated design of our 2" Mecanum Wheels to our FIRST market.
Both of these products have just been added to the V5 Wheels page, officially making them VRC Legal!
Each set of 4 wheels also includes the necessary VersaHex Adapters to make the wheels compatible with High Strength Shafts
Ngl, those 2" omni wheels don’t look like they’re going to give a smooth ride. But bright side is we got a new size, which will fit with my 2 in flex wheels for a drivebase!
However, when are the 4 in mecanum wheels going to come back? It seems like they’re missing from the wheels page.
ooooooh these are cool. 600 rpm drive is now a top prospect even for drivers like me.
Looks at wallet
We will surely have a VRC water game before I can buy a set of these.
These look like they wont work great for drive trains but could be super good for tracking wheels and odom pods.
Two questions:
Are the rollers the same on both types of wheels? If they are, that is a very cool manufacturing hack.
Whats the chances of just adding them to the VEXIQ legal parts? Haven’t had any VIQ love recently, this would help tamp down the jealousy.
these will be so got for odamaty
besides pneumatic… i feel like VICQ pneumatics is super hype. i would have loved to had pneumatics in IQ. Although i will admit the pneumatics dont seem super sturdy or strong so mabey giving them more pressure would be nice.
The mecanum wheel CAD is rough, but it doesn’t look like the rollers are the same.
i’m in vex iq and i’m really curious about this:
How do the 2nd pair of omni wheels work?
@u89djt Thanks for the pictures and the math lesson! It’s pretty easy with the diagram to see the difference between the two.
@dabigman Lets assume the standard clawbot base (two motor drive, front wheels geared to the rear wheels.
If you put omni wheels on the front traction wheels on the back, when you turn, the center of rotation is between the traction wheels (close enough for this).
If you put omni wheels on all four wheels, the center of rotation moves to the center of the robot.
That’s why most teams use 4 omni wheels.
I’ll leave it as an exercise for you on how it turns if you put omni’s on one side and traction wheels on the other.
Here’s the swept volume of one half of a left or right 2" mecanum wheel:
2inchmecanumvolume.step (107.2 KB)
and of a 2" omni wheel:
2inchomnivolume.step (58.2 KB)
Not much space for jutting static structure to claw back from the space taken up by the wheels, but some in the mecanum. There are volumes like this for the 4" mecanums and the older omnis in the simplified CAD library file I posted.
Yum. My robot will be shaken apart because of that bumpy ride those 2 inch omis will give.
Hey Y’all!
I’ve been out of pocket the past few days recovering from a nasty case of the 'rona that I caught over the holidays 
Spinning back here to try and give some context & answer some of your questions about these wheels!
These wheels were originally designed to be a VEXpro product for FRC intake applications. A little bit into the design process, we realized that these could play well for some VRC applications as well, and worked to make them cross-compatible. They have been tested across a few various VRC applications and, similarly to FRC, perform better in intake applications than they do in drive applications. This is not to say you can’t try them as drive wheels, but the original intent for these wheels has always been for intake/game piece manipulation applications.
The mecanum wheels are similar to the existing 217-7400 set, however the cantilevered nature of the rollers on these new Mecanum Wheels help alleviate the largest pain point of the prior revision; the severe lack of clearance between the rollers and the plastic hub. When the 217-7400 wheels were used on foam tiles in drive applications, or on intakes, the actual strafing maneuver or centering of the object was inhibited by the fact that a game piece or the floor tile would interfere with the central plastic hub. The Cantilevered rollers on this new wheel help make sure that you’re ONLY contacting a rubber roller when the wheel is spinning.
Now to try and answer some questions…
Because the Omni Wheels were designed with intake applications in mind first, they are designed such that you can clock the rollers along a shaft. The bore is not perfectly clocked to the rollers, intentionally. A fully assembled roller with these wheels can be made with offsetting rollers, helping to smooth out the “gap” you’re worried about.
And in all honesty, they still roll pretty well by themselves
Most certainly. No more cutting the double wides in half!!!
Nope. You’re right, it would be sweet, but as explained by @u89djt, the rollers have inherently different geometries, neccessitated by mecanum geometry.
Not on the roadmap currently. IQ already has an Omni Wheel that works better with the system than this one would. IQ Mecanums have been tossed around as an idea for awhile here. It sort of always falls to the wayside, because we’ve yet to find a way to convince ourselves than anyone in IQ would want to commit 4 motors to mecanum when you only need 3 motors for an H-Drive. Not saying we’ll never drop IQ Mecanums, but the ease & simplicity of assembling and coding an H-drive sort of makes an IQ Mecanum a “maybe nice to have in the future?” and less of a “critical part needed to add to the system”. Maybe we’ll change our minds in another year or two, who knows.
Feel free to chime in below with any more questions and I’ll try to get to them!
Glad you’re in better shape. We should say out loud that the gaps in the rollers are actually lined up in that shot. You need an offset more in the region of 60 degrees to place the gap coincident with the main surface of a roller. I wonder if that could be achieved with a combination of adaptors? The one that comes with the wheels can’t break symmetry, I think, and so only gives you 180 degrees offset, which doesn’t change the profile.
Yeah, unfortunately the 1/2" Hex Bore allows for better clocking than the 1/4" Square Bore. Sacrifices had to be made somewhere when we decided to try crossing two hurdles with one jump.
Yeah, this will help alleviate the concern here as well. But I will say that I believe the gaps look worse in pictures & CAD than they actually are in reality. The wheel rolls pretty true.
Thanks for the update, hope you are feeling better.
Yea, the H drive is pretty sweet for IQ, I get that there isn’t a compelling reason. I did order a set (and the adapters to get the shaft down to 1/8") I’ll throw them on one of my test robots and see how they roll. (I have a couple of just drive bases with different formats. Elementary roboteers love the useless (and illegal) Leg Wheels ( https://m.media-amazon.com/images/W/MEDIAX_792452-T1/images/I/41pnnFkCZRL._SX425_.jpg)
Yes, they’ll rattle past very quickly to the extent that momentum and flex in the system is unlikely to care much in the overall behaviour, but bearing wear will be higher.
Oh hey, I have a dremel and an attitude - we could make 60 degrees happen if /really/ necessary 
