We’ve been discussing this recently and wanted to know what you all think. From what we know, the main reason mecanums aren’t currently used is their size and weight. However, with V5 coming out with much more powerful motors, will we finally be seeing these wheels utilized from next season on? There are a few advantages in using them (torque vs x-drives, easier to build) and pretty much every other big robotics competition (FRC, FTC) utilizes them.
Will the 2018-2019 season be the rise of mecanums?
I’m not sure. They still have the issues with size and weight. Also they need 4 motors. That will take up half of your 8 motor limit so may not be popular depending on the game.
X-drives do too anyways, unless we are going to start seeing H-side-drives. Our thought is that they must have designed the game to use less manipulation than this season if they are limiting the amount of motors the way they are. Plus, you see some pretty crazy robots in IQ with just 6 motors.
I know of teams that use 4 motor drives in IQ, and they only have 6 motors to work with. I honestly wouldn’t blink an eye if we see 6 mtr drives next year.
That 100% relies on having a lower number of subsystems next season. Like this year, good teams have 5 (Drive, mobile goal lift, main lift, secondary lift, and intake). If next year has less subsystems, like in starstruck (Drive, lift, claw), we could see 6 motor drives.
Here’s an analysis of subsystems in past VEX games:
Skyrise:
2-3(drive, lift, intake, intake can be passive)
NBN:
3-4(drive, flywheel, intake, maybe partner lift)
Starstruck:
2-3(drive, lift, claw, could be passive)
In the Zone
4-5(drive, lift, adjustment, mg, intake(could be passive))
As you can see, even in In the Zone you could pull 2 motor lift and 4 motor drive in V5 if you ran passive intake and 1 motor secondary lift and mg. And this is with games that are designed for 12 motors; the new V5 game will likely look more like VEX IQ games where you can get away with a 2 motor intake and delivery system any day.
I’m a V5 beta user, I have a holonomic frame clawbot waiting for code, it’s a quick change to the mech wheeles. Stronger motors mean less on the grippers. Happy that engineers are back vs moar motors.
A couple of weeks ago a push-bot with mecanum wheels in “plus” configuration was able to beat two, arguably, the best robots in our state!
Seriously, in Final #2 three robots out of four overheated PTC and died, while plus-drive mecanum push-bot (3rd pick) was able to push three blue mobile goals into 5 point zone. This was the highlight of the competition. I wish I took a video of that game.
US Navy was one of the earliest users of mecanum wheels when it had omnidirectional forklift trucks that could maneuver in very tight spaces such as the deck of an aircraft carrier. In some places where they had to operate there was barely enough clearance just to drive, let alone enough space to turn around.
Unfortunately, unless one of the future games would have pathway or a maze with 20" clearance between the walls, it is very unlikely that benefits of the mecanum wheels could outweigh their disadvantages.
With mecanums for the ability to drive sideways at any given moment of time, just as easily as you drive forward, you have to pay with bulkiness and extra friction that requires more torque and limit your ability to gear up.
Onmidirectional X-drives have similar trade-offs but they take less space and are very good for the games when you need to turn on a spot.
It is heavily dependent on subsystems and I agree with @Dokkaebi I can’t see good teams doing 6 motor base though unless you want to be a pushbot or its a game like this year that is dependent on skills bot for skills.