We have heard of a team running a 6 wheel 6 gear box robot we don’t know if it’s legal for actual events but would like to try it And what’s are the odds of a double distribution panels being allowed
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Any number of wheels and gearboxes are allowed as long as you don’t max out the ports on your PDP or PDH. You are only allowed one power distribution panel per robot.
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If you want a 6 motor drive then two of the 3 motor transmissions will be the most efficient way to achieve that result. 1 two stage gear box will have lower frictional losses than 3, a single transmission with all motors tightly clusters will have a single smaller footprint, and assuming you are buying new transmissions likely cost less too.
If you want 6 individually driven wheels I have to ask why? With a drop center 6wd robot at best you’ll only be able to use power from 4 of the motors at any given time and in a serious pushing match you may only get any significant tractive force from two of the motors as the normal force on the center wheels is lowered and they become more likely to spin.
With a 3 motor gear box the torque from all three motors will be split between the 4 wheels on the ground with only a small amount used to overcome the friction in wheels that don’t currently have any normal force applied to them.
A flat 6 wheel does eliminate some of those problems but introduces others.
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We had a 8 motor 6 gearbox drive system
Gif below
Also a reddit post showing more of the chassis design
We mixed NEOs to have Tank drive on a toggleable Pnuematic arm and the X drive is falcons that are adding to the tank drive or regular holonomic.
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Couldn’t afford swerve! Literally that and we had done x drive for two years previously. We wanted traction tank for defense this year. So…
Edit: we already had the falcons for x drive and the gearboxes. We could afford the new neo gearboxs from rev and 4 NEOs. New falcons were on back order for months even though we were trying to buy in November to replace our 3 year old ones. The team debated this alot and we even have a tank only practice chassis using CIMs and scrap KOP gear boxes too because of that. They went through 4 different materials and iterations of the design to end up with the final aluminum one. At Kettering we had an acrylic chassis that broke during the course of the event. We had done acrylic 2 years previously but forgot the ribs this time. It was a good learning lesson and also now is a pretty cool decoration!
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But the moment it worked, the entire team was like this:
Totally worth it, let the students try some crazy ideas.
Quote from this video: Woodie C. Flowers SM '68, ME '71, PhD '73 - YouTube about 28 minutes in
“Once you take a job, the chances that you will have to reinforce your own creative self image are pretty slim. Because the stakes begin to get really high so you pick a conservative path. While you’re a student you have a safe opportunity to learn about your ability to be creative.” - Woodie Flowers
The moment a crazy idea works is magical and something every team should experience. Making the same cookie cutter chassis as everyone else is fine, but if they want to do something totally wild I’m not gonna say no. They had a solid game plan to make it happen. That’s the whole point of why I keep coming back. The creativity is phenomenal
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all of my favorite teams are ones that consistently come up with cool unique mechanisms to solve a problem that sure could be solved with something simpler, but instead make their own path. your drive train is inspirational to me at the very least and makes me excited to do robots!
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In fairness here, waaay back in the day when swerve or crab was first pitched at a FRC team meeting I am sure there was all sorts of “that’s crazy” floating around the table.
For the record I absolutely love kiwi drive. 3 motors and you get true omnidirectional control in a tiny footprint. Part of me wonders if it will see a resurgence if FRC lowers motor counts to make swerve a harder call.
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I really hope in a decade from now someones gonna say “in fairness here, waaay back in the day when X-Tank was first pitched at a FRC team meeting I am sure there was all sorts of “that’s crazy” floating around the hover table.”
Oooo I have something for this… Killough Drive but funky! It’s an off-season idea.
It’s like kiwi but with the wheels 90° from normal. You can’t swerve nearly as well but you do get more pushing power and could maybe hold steady on a ramp better over kiwi.
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I love unique drivetrains.
The team i mentor now did the same x drive with drop down tank in 2019.
Team i use to mentor did a 6wd that had a droppable middle wheel so you could “wheelie” the front in 2016.
And i was the designer of this DT wayyyyy back in 2008.
Which im pretty certain became the ancestor for things like butterfly drive.
Huge fan of creative DTs! Keep up the creativity!
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This is the Mercedes drive. Can’t tell me anything different. 
We printed a nicer version using omnis from the robot shop. The idea is to make it run from a Jetson nano possibly with arduino megas and use up our old victor SPs with pwm.
Definitely has more of a Mercedes/biohazard warning vibe with the filleting. We were able to push that one around on the floor and figure out how the wheels need to turn to do different motions. It also doesn’t turn 0 degrees nicely.
Thinking about this now, if you placed it on top of an exercise ball you essentially can drive the ball any direction…
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Roboteers used 5 swerve modules in 2022, along with two deployable wheels to climb
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I’m a big fan of octocanum***, so I imagine this hexakiwi drive would be pretty fun. My main issue with it would be that you could still get spun pretty easily. Looks pretty fun!
***It’s pretty easy to implement and, while grossly inefficient compared to swerve, the built-in gear shift in traction mode is (gasp!) an actual advantage over swerve.
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Technically, you can run another PDH/PDP if you take the plastic housing off and call it a custom circuit
You’re just begging to be spun around now.
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Also R503 + R504 + R621