I don’t see and xdrives being used in over under. Any cons to not use xdrive?
My team is using X-drive and it works amazingly, to fix all cons you just need to put wheels in the middle part to get over the bar on the field as shown in the image below -
X-drives are very slow and can be complicated to control.
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I disagree. We used an X-Drive last year and it was not slow at all.
Normal arcade control works (plus strafe) for x-drives. I find that arcade is easier for controlling. (Compared to say tank drive.)
Though we can all have opinions…
- Henry 344E
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X Drives are usually bad at pushing, because a traditional x drive can only have 4 motors while a lot of teams prefer 6 motor drives, and x drives are actually sqrt(2) times faster and weaker then a normal drive with the same wheel speed. You can add in more wheels and motors like koen suggested, but this makes the drive a lot heavier and complex, on top of the already complex normal x drive. You also can’t gear together all of the wheels on the drivetrain, meaning if part of your robot get lifted off the ground (like by another robot’s wedge), the motors attached to wheels which are off the ground are no longer helping the robot drive. X drives also reduce the space at the front or back of the robot to fit an intake, forcing you to make a big robot for a game with an already cramped field. And specifically for over under, x drives are a lot harder to climb the barrier with.
The ability to strafe, the x-drive’s biggest pro, is also usually not even necessary to preform well and most teams won’t be able to benefit from it because of lack of driving or programming skill. Before choosing an x-drive, I would highly recommend thinking about how much you would actually benefit from being able to drive sideways by thinking about how you would route your auto programs and when you would use it in driver.
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X drives have a much harder time climbing than other drives. This is why x drives weren’t used in TiP but were a bit in SU and CU. Over under is probably the most climbing focused game since TP so it makes sense for x drive to not be used.
Wrong, x drives are actually faster than a drive of the same wheel size and rpm.
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X drives cant climb barrier. X drives generally have less torque. X drives are harder to program. X drives cant have a 6m drive withought some asteriks drive goofiness. There is a reason why tank drives are the meta.
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x drives struggle in VRC because you can only really take advantage of the strafing abilities in a match at higher RPMs. i found that 360 rpm 4m for x drive is the cream of the crop for x drive as it runs about 400 rpm due to the goofy math involved. but then you run into the lack of torque issue and as you stated, asterisk is the only way to counteract that
I posted a drawing of an X-drive that can get over the bar, please read it. It does not have many cons and it gets of the bar quite well, it also uses 6 motors
its really not that hard to program you just need to understand the way it moves
wow its nice to know that were not the only team doing x drive in over under do you mind sharing a photo i would love to see it get over the bar
Or a 11 watt torque motor?
The x drive I built has an intake and space for a catapult (in the future) and we made it relatively small
For some reason, I thought X-drives didnt use omni-wheels 
In general, X drives are significantly slower than tank drives because they require much more structure to build. More structure makes a more massive robot which both increases inertia and compresses the foam field tiles under the robot, making movement slower.
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I’m surprised you say that. In a perfect world, x drives will go √2 times faster because of the wheels’ orientation. Of course we do not live in a perfect world. Weight is a factor. But even if you use 8 VEX steel gussets, the gain in weight is trivial. Not enough to slow it down that much. Especially if you use polycarb gussets, which are lighter than VEX aluminum.
I am not saying that I would use an x drive this year. But I might have if I were in VRC last year. This year, the ability to strafe is kinda meh.
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I am sorry, my team’s robot is packed up right now for we have a competition early in the morning tomorrow, I will try to get back to you as soon as possible.
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yes but i is really slow and they all just gets pushed around so easy. like its not funny. a two motor 600 rpm could push it so easy. they are not good for the game this year at all.
yeah but that would be a whole mess
Strafeing is really important to use but the only problem is you need to get familiar with being unoriented since you drive on the side of the field also we had our first comp and we didn’t get pushed at all