pic: Dodecacanum Drivetrain



Because a two drivemode octocanum just wasn’t enough.

neat.

I assume you depressurize both cylinders if you want to drive traction mode?
Very interesting design, although I don’t know of a driver that would be able to make good use of all 3 modes. Maybe mecanums for auton and traction/omni wheels for the match, but it’s an edge case.
Do you have different ratios on each wheel?

Also, your omni and vectored intake wheels don’t line up with the ones on the other side. Unless you wanted them to be offset for some odd reason.

minor details

Yep. Colson wheel is lowered an 1/8" so it is the only one touching the ground when both are depressurized. Same ratios on each wheel but one could easily change up the 20 DP gears in each module (barely visible in this pic, upper left module) to have a low speed mecanum mode for example. That’s what we did on our octocanum this year: about 8ft/sec in mecanum and 16ft/sec in tank.

woops…

Tank for pushing, omnis for turning, mecanum for going sideways. I see no way that this is overengineered.

Now just put each of these on a swerve module and were covered!

I mean, why stop there. Why not add a pto and a disk brake to each one of those modules to get the most out of it :wink:

If you deploy just the 4 omni wheels, can’t it only drive straight? I though you needed at least 1 omni per 90 degree angle for it to work correctly.

Four inline omnis make a fun-driving chassis. Drift turns and spins, and no T-bone pins! Check out the 2014 Team JVN Buildblitz video.

The omnis are probably for getting pushed from the side. The faster you get pushed into the wall, the faster you can drive out of it.

Edit: sniped by Richard

This actually keeps you from getting stuck in a moving pin. With a traditional skid steer robot if another robot can break your traction loose from the side you will basically be stuck on that robot as long as they keep moving. The forces pushing you against the robot and your lack of traction make it impossible to drive off of them. With the omnis those forces pressing you against the other robot are next to nothing, allowing you to drive away instantly (don’t need to wait for the wall).

Not quite… he has to add decagon wheels for the increased traction.

It’s hard to tell with the perspective, but watch that your traction wheels have a sufficiently wide track to wheelbase ratio. It may work better for the traction wheels to be outboard rather than inboard.

If you switch the front and rear omnis separately, you can add two more reasonable drive configurations.

Edit - OH WAIT - is the gear across from each traction wheel on the same axle as the wheel, or is there a differential to reverse the direction of rotation? If just an axle, the traction wheels will be spinning the opposite direction of the holonomic wheels.

i am actually a fan of treads. this design is obviously lacking in that respect.

Dagnabit! It’s always something.

Goodnight, Roseanne Roseanadana.

You need to make icosacanum. Colsons, mecanums, omnis, treads, and pneumatic wheels. And each 5 wheel set is on a swerve module, can shift gears, and has disk brakes.