Tipping Point Design Concept - 2 Mogos in Under 1 Second

Here’s my first design concept for the season.

The idea is a robot with a pneumatically activated pusher mech and set of claws. The deploy allows it to shove off of the wall in a direction perpendicular to the direction of the wheels (sideways), propelling the robot towards the neutral mogos in auton way faster than would be possible with motors.

I am aware of some of the flaws with this design, and things that could be improved. Firstly, the pusher leg needs to actually have enough power to propel the robot all the way towards the center. Secondly, we could get closer to the mogos to start if we used a kickstand to get over the line a bit, and pushed off diagonally from the platform base, instead of the field perimeter.

Tipping Point

Tipping Point

Tipping Point
I intend this post as a starting point for discussion about the unique strategy that would be using the wall to push off of, and am interested in any ideas anyone else might have about the best ways to go about doing this.

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I really like the idea of pushing off with a rubber band actuated mechanism to get a speed boost at the start of the match, and being able to take advantage of a standard omni wheel drive’s sideways freedom. but I don’t know how consistent it would be to propel off of the field perimeter. For this to be very reliable it needs to not rely on very high accuracy, or you need to use some form of position tracking to correct error in the launch.

another problem is that now you have a long stick poking out of the side of your bot, and that might be a problem. But there’s probably a way to passively retract that as well.

so yeah I think this is a viable alternative to something like a transmission or shifting x drive to achieve a fast start at the beginning of the match, and I wouldn’t be surprised if something like this does get used competitively

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Funny you should mention it, but in the animation the robot starts not lined up with the center of the two goals, and has to use wheel power to move a few inches to the center.

Theoretically there’s some tracking wheels in there too to make it work.

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Keep in mind that some of the walls can be a little more flexible in the video, making things like this hard. Nice animation and concept, though.

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The fast start is really useful, but I don’t think dragging these goals is the way to go. Getting both of them means you would need to drag a lot of weight and the foam tiles would increase friction.

Why did you turn?

Still, a cool design concept that takes advantage of pneumatics.

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But you cant climb the ramp?

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The only problem I see with this design is that at a certain point, the field walls will start bending out of the way and the robot’s acceleration will be capped

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I feel like it is a solo idea, but it just won’t be practical. The robot won’t be able to climb with the goals just being dragged. It will also not be able to score ring effectively. Also, would it go against the “robots must be able to easily release game objects after a match” rule?

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You might be able to do it with one, if you have a dr4b you could probably fit one of the mechanisms if you made it more flat on the back or under. One strat you could do is put a goal hoarder on the back of the bot and start it backwards during auton and have it take out the goal you don’t want the enemy alliance to get and then you have a goal strapped to you until the end and cut it loose before balancing. It might be worth it losing auton if you can deny them a very important goal.

Oh yo! I remember you from the Space City Showcase! I’m from 33848B, the Louisiana team.

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Me when the physics teacher said friction can be ignored. The omni rollers will die

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Hellooooo! Glad to see you here!

yeah, its too large and wide on either side to go up the platform. also, the 4 omni drive restricts ground traction, which makes it even harder to get up.

actually, omni wheels provide some of the best possible traction. Just because they can slide side to side doesn’t mean they can’t have excellent forward grip on the tiles, which they do.

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mhm
maybe, but ill stick to my half traction half omni drive lol

don’t take my word for it, here, have some data:

if you look at the experiments done in this post, you’ll see that 4" omni wheels have the best traction on both polycarbonate and foam tiles, while 4" traction wheels actually have the worst traction on both materials over any other wheel type.

Results like these are why it’s important to make your decisions based on data and experience over simply intuition. While traction wheels sound like they’d have a lot of traction, in reality they’re the worst. And the slippery sideways nature of omni wheels might lead you to think they have bad forward traction, but actually they’re the best.

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ah yes but I’m using 3.25s

haha yes a crabbot that dances that would be a very good idea mhm

again, take a look at the chart. 3.25" still rank higher than traction by a large amount. And it’s pretty clear why 3.25" are less grippy than 4" and 2.75", because the rubber of their rollers is less squishy and grippy.

However, it’s not super important to optimize traction because all you need is enough traction, not the best. As long as your wheels aren’t slipping during the match, that’s enough traction. The only moments where optimizing traction past that good enough level has any benefits is during pushing matches, which while useful, probably isn’t worth the sacrifice you make by giving up all the other advantages of 3.25" omnis in favor of the traction of 4".

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