I have been thinking about what the best drive base for this year would be. In my op a 6 wheel 4M tank drive (traction wheel in the center) would be the best especially to avoid being pushed while trying to score. And I don’t think a holonomic would be great this year because the bots will have to drive over a lip to get onto the scale. This is jusy my op though so I’m curious what others may think would be the best for this year.
I personally think mecanums. I think that the maneuverability will be great for picking up the relatively small rings, but it should have enough power to get up the platforms.
Mecanums are pretty maneuverable but vex doesn’t make them that well. They are also kinda oversized but it could work well if you have a specific plan ig.
if you focus more on goals and defense, a 6 motor drive is definitely viable, especially with the ability to use pneumatics with no penalties.
However I still think 4m tank drive is best for a well-rounded robot.
I agree that holonomic drives don’t seem especially useful, but as usual they can be good if they’re of high quality and programming takes full advantage of them.
we might see more locked omni or traction wheels on the middle of 6 wheeled drives since defense seems like it could be prevalent.
Drives will also be huge because of how massive the goals are.
As far as the drive speed goes, there needs to be a balance between speed to snatch the tall goal during auton, and enough torque to cart around these heavy goals. I’m thinking anything in a range between 250-300rpm on 4" wheels will be decent.
Differential swerve will be the best drive type.
I wouldn’t be surprised to see some 2 speed drives that use pneumatics for a transmission. Have a super fast speed for snatching goals, and a more balanced speed for other times. Would be complicated, but might give a good advantage for skills, and competitive matches.
That’s true but if someone makes a piston system with the pneumatics it’s going to be pretty hard to control because the pneumatics are always full throttle.
it doesn’t use the pistons to move the drive, it’d be like this but using pistons instead of a motor to shift gears:
That’s still extremely powerful though. If used consistently there is a high chance of bending or a break. In the case you figure out a way to lessen the power, then that would likely be a pretty good idea.
what would bend or break? the gears would clash temporarily, which could be problematic, but if you file down the edges of the gears into a taper it would be a smoother transition.
I don’t think a shifting drive is a good idea until you have the rest of your bot figured out though, there are more important things to focus on.
I’d say mecanums could be very powerful considering how close together some of the rings are together, but at the same time, they take a considerable amount of space on the drive train (I think the smallest I’ve gotten is a 5 hole gap on a direct powered drive). Since the mogos are 13 inches wide it might be a tight squeeze. Of course, you could have a flipout mogo grabber but I’m not exactly sure how it’d work. This is all my thinking though, I don’t have any parts with me.
Side note, how did I get regular? lol
me and my team are thinking of a 2 motor tank drive drive since we are using 1 motor for MOGO 2 motor DR4B 1 motor intake an d 1 motor scoring mechanism. We have 1 motor left currently so we plan on using it for strafing. Any thoughts?
I’m not exactly sure how it’d turn out but I would think that it’d be pretty susceptible to pushing, and especially in a game where it seems almost capture-the-flag-esque, being pushed around the field isn’t gonna be a great time
I understand and this was a huge part of our teams’ discussion but unless we can cut a motor somewhere else we can’t think of a better drive train. sidenote I personally don’t want to run a 1 motor DR4B so I’m out of ideas
You can maybe substitute the DR4B for a chain bar lift with only one motor
we were thinking of that but we thought it would be unstable and very heavy.
there are ways of doing a motor less mogo mechanism using pistons and elastic bands
If your team does not find a good reason to strafe the final motor will go to good use as a “booster”. In my experience with a heavy bot, the booster wheel does a lot to make the forward and backward accelerations quicker
I am planning on doing a 600 RPM geared down to 300
At least in my opinion, 4 motor 200rpm base (4in). Has great pushing power, but less speed. I guess we are just gonna need to make something to grab the yellow mogos faster