Hey! My team and I were wondering which wheels to use for this years competition. What do you guys think would be the best?
I think almost drive types are viable this year. The only drive I would not use is an x drive as they have a lot less traction. All other drive types should easily have enough traction to climb the platform.
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probably omnis and locked omnis with a six-wheel drive, since the omnis allow for improved turning and the locked omnis retain traction(as there will be competition over mogos).
Tank drive, h-drive, and mecanum variations of the drivetrain described above will work, but i wouldn’t recommend x-drive, as it may be hard to climb the platform and it can lose traction.
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I wouldn’t be so sure about that… an X drive theoretically has the exact same traction as a standard 4 wheel omni drive. The only difference with an x drive is that it moves faster, but with less torque, which means it might have a hard time climbing due to torque problems, not traction.
But I wouldn’t recommend X drive this year because I don’t see any specific advantages strafing has. Of course, a team with a good driver and good programmer can always make great use of an X drive, but for everyone else it probably has more drawbacks than benefits.
Mecanum wheels do have less traction than standard omni wheels, and have a few other issues that generally make them viable, but not the best option. I would expect a mecanum drive would be worse at climbing than an x drive actually, assuming that the two drives are moving at the same speed/torque, and have the same weight.
I think a standard 4 wheel or 6 wheel tank configuration will be the most common as always. Perhaps teams can get creative with flex wheels as the central wheel for extra traction, but that doesn’t seem necessary.
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I tested an X-drive chassis on the platform this year. It’s the standard affair: 200rpm, 3.35" wheel, polycarbonate brackets. I tested it climbing the platform and it couldn’t get off the ground. Traction actually was the issue. The omni wheels were spinning out and not gripping the platform. It seemed like the omni wheel rollers were making this happen.
You may be right that X-drive theoretically has the same amount of traction but from my experience, it is unable to climb the platform at all.
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I have found this as well. I tested both of my x-drives a 4" one and a 3.25" one. The 3.25 x drive had my change up robot on top so it did weigh more but the 4" one did not have any thing attached to it. Both drives couldn’t make it up the polycarbonate platform. I found that 4" drive with minimal weight could almost make it up and all it needed was a small push.
I agree that from experience the x-drive has less traction while attempting to climb up the platform.
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I also tested this exact setup and had very poor results even when trying out different robot weights. I do not recommend an X-Drive with 3.25" wheels this year. I could see the 2.75" wheels working as they have more traction, but I still don’t see them working well.
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