Triple balance? Not that hard

I revise my opinion about the difficulty of a triple balance from “practically impossible” to “really not that hard”. As long as your alliance has 2 swerve drive bots. The ones on the ends go on first, balance, and drive off the ends to make room for the one in the middle.

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What are the frame dimensions on those bots?

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Now do you think that on your alliance that there will always be at least two swerve bots that will be able and willing to do this?

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29x31.

These are looking at the 31" side. If they were turned to the narrow side, there would be even more clearance.

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In quals, maybe. In elims, definitely.

Because of this dynamic, swerve drive bots will rise to the top of the W/L rankings. If you don’t have a swerve drive, you better practice being the center bot, or figure out how to drop one side of your drivetrail off the edge of the charger without tipping over. If you can’t, you’re a -10p liability in the end game.

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And if one of the bots is bumped/slides off the side when the third one has to barrel<1> up the ramp?

<1> so far I’ve not seen any video of a climb I would call sedate and controlled (eg Charging Station Swerve Drive Testing and Construction Ri3D Redux 2023 - YouTube )

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Having swerve bots on your alliance is likely at strong events., however, having those teams agree to overhang the edge of the charge station for a triple balance may not happen.

Say it with me: build small robots this year

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If you have 6 wheel WCD, you can go up on one side, turn towards the other and drive 2 wheels off, probably getting more of your robot off than a swerve could. You just have to bias your CG to one side or the other. It also requires going up first, but will leave a lot of space for the other two robots. By doing this you also keep 4 wheels on the ground which will give you more traction to stay in place while tipped than you would have with two wheels away from center of gravity on swerve.

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Keep in mind that the lip on the edge of the ramp is thinner on the field element than on the plywood simulation.

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It’s not clear to me that the difference between .7244<1><2> and .7145 is truly significant.
I’m also suspecting that the coefficient of friction of the “real” element will be a fair bit less than the plywood version

<1> 3/4" * cos(15°) = .7244" (and if your plywood is really only 23/32", it’s actually thinner than the real element)
<2> plus the thickness of the velcro loops if you install them

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Seems to me it would just as easy if not easier for 6 wheel kit bot to drive off the edge than a swerve.

Once those wheels are off a swerve is done.

6 wheeler can drive their lighter end off the edge and still have 4 engaged. Not to mention, once turned sideways, you don’t have to worry about rolling off while the station gets tipped by your mates joining you.

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Note that if any bot is touching the ground at the end, none of the bots can get the balance points (6.4.2). You would need to be very careful when doing this. I think that this will happen accidentally and results in the same as a bot touching a traversal bot last year.

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downwards-facing electronics go cromch

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“as long as there are 2 swerve bots” feels like a very important assumption that usually won’t be true.

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It’s been mentioned elsewhere in the thread, but it’s really regional dependent. I suspect the top 4-6 alliances of every California regional will have 2 swerve bots. Less so at something like Smoky Mountain.

The whole “cantilever the bot” idea is also valid with other drivetrains for what it’s worth. Just as long as you’re driving less than 50% of the bot off the side, you can make it happen.

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Second this. This is not a swerve specific maneuver. Any drive train can do this it just may require a 90 degree turn.

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I don’t think teams using MK4i modules like this strategy very much. :laughing:

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Or the meteoric return of H-drive :thinking:

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I’d be curious to see videos of how close you can get your center of gravity to the edge before violent tipping of the platform from other bots getting on starts causing issues with bouncing you over the side. (Hit hit, for those who managed to build one already and have extra robots around they don’t mind tipping over :wink: )

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