I have noticed that there are many different approaches to the drive of robots this year. What are the reasons teams decided to use the drive that they choose? What are the pros and cons of each option?
My team decided to use a holonomic drive with four speed internal motors direct driven. We use it for the speed and the great manuverability.
We are using a 6 wheel drive consisting of a high traction in the middle and two omnis on the outsides to allow to turn smoothing and no be pushed as some other robots have been.
we use the well loved banshee drive. this consists of four mecanum wheels in the corner, and two traction wheels in the middle. Yes this means we cannot strafe, I know. But it does have some advantages. We have a direct 4 motor drive, with the motors geared internally for speed. This makes us slower than most teams but we can push hard. the mecanum wheels in the corners enable us to turn with more torque than a standard tank, and the traction wheel in the middle helps with traction. The idea is we can out run anything we cant push and we can out push anything we cant out run.
Middle traction wheels would make it harder for an effective t-bone, as the wheels would create more friction with the ground than omnis or mecanums, thus making it harder to be pushed. Perhaps I am missing something, so if I am, please elaborate or rephrase.
@Collin Stiers
Question about the banshee drive, why not use omnis instead of traction wheels? The mechs can still avoid being t-boned and you can still strafe and turn as otherwise
One of my three teams used a holonomic drive and it was superior because you could rotate like a turret for aiming. They had a variable that was passed to a drive function. It would be set to low settings for aiming and high speed for maneuvering. It is pretty awesome. I can share the code if anyone is interested.
Well if under defense the holonomic drive won’t be able to function the same turret because the drive won’t rotate when someone is t-boning you. Plus anyone running 6+ motors is going to be faster and is basically going to win every pushing fight.
Have thing middle wheel actually makes it harder to get out of a t-bone. Yes it is harder for teams to push you side to side but they are going to stall your drive easier with the center traction wheels. Over all it would be better to let them push you without your drive running then spin out and away from them.
I have never had that happen… This drive style actually helped us win our tournament last weekend as in autonomous we stopped in front of our opponents square, and they ran into us and burned out their drive but ours was perfectly fine. We haven’t burned out more in 2 tournaments since we switched to a traction wheel in the middle. We use them for the reason also that when we are at the bar, we don’t want to be able to be pushed aside away from the goal.
It really depends on what drive is pushing you. If a robot with a good torque drive pushes you the traction will help but they will still be able to push you. If robots don’t have good torque and they know what they doing they will it you in your corners which will still turn you. This is arguably the better than t-boning as you turn their shot instead of their horizontal position.
we only have 4 motors on the drive. If we had 6 independent motors your idea would be great. unfortunately we have no way to drive the center wheel independent of the two edge wheels. so if we did that we could only strafe at weird diagonals
We use an X drive because we wanted to try it this year. We have tried almost every other type of drive train, so we thought we would give this one a shot. One of the big issues is it’s REALLY slow (although, we ARE only running 1:1 with high-speed :)). Also, the turning is really hard to control, which make aiming quite difficult.
I have 8 motors on my base and 4 motors on my flywheel. On my intake however, two motors from the base are also used to drive the intakes. This enables my intakes to run while I am driving. I also programmed my way around a lot of problems.