pic: Lightweight 8 CIM Shifting Swerve Drive Chassis

[Bryce2471]

loading photo ...

[Tyler2517]

This is officially my Favorite swerve concept to date. Only a few questions...

Will this cause brown outs or systems to fail due to the massive amount of power being consumed when accelerating/turning?

You will be using almost all if not all of your 40amp slots to run this, is it that much of a advantage in speed/mobility to do this?

For field centric control can you update in time with this much acceleration/speed to keep every thing consistent?

[asid61]

Very nice! Is that weight with all fasteners, etc? Do you have any pictures of the module itself?

[Munchskull]

Looks great, but does it really need two CIMS on each model?

[magnets]

Looks awesome, but isn't "lightweight 8-CIM drive" an oxymoron?

[Bryce2471]

Originally Posted by Tyler2517

This is officially my Favorite swerve concept to date. Only a few questions...

Will this cause brown outs or systems to fail due to the massive amount of power being consumed when accelerating/turning?

You will be using almost all if not all of your 40amp slots to run this, is it that much of a advantage in speed/mobility to do this?

For field centric control can you update in time with this much acceleration/speed to keep every thing consistent?

Thanks!
In this design, auto shifting code would be used so that any time the speed was low, it would be geared or 12fps, which I believe this low enough to the breaker.

That is a good point. With the new power distribution board, ths will use all f the available power except 4 20-30 amp slots. That is a major disadvantage of this design, but that would be more than enough to build a robot in three days type manipulator this year. My goal with this drive train desing was to make an 8 motor shifting swerve drive small and light enough to be usable for a drive train dependent game.

We are implementing a limit on rotational acceleration for control-ability, weather or not we use field-centric code.

[Bryce2471]

Very nice! Is that weight with all fasteners, etc? Do you have any pictures of the module itself?

It includes everything you see in the picture. I've still been too lazy to find CAD for small snap rings because their weight is negligible, but I think I've got everything else accounted for. I'll post a close up of the module soon.

Looks great, but does it really need two CIMS on each model?

No.

But I it would be nice! In some games, extreme amounts of drive power and maneuverability is desirable enough that a drive train like this would make sense. Although, I'll admit that it's unnecessary in most cases.

Looks awesome, but isn't "lightweight 8-CIM drive" an oxymoron?

Kind of ;D
I guess this calls for the picture to be renamed...

[asid61]

Two cims or a cim/minicim combo per module is the new metagame. You need those to go higher than 18fps, and it's useful for lower speeds.
In any case, what were you going to use them for, it not for drive? With the abundancy of motors these days, there's no point in not doing it...

[Tyler2517]

Originally Posted by asid61

Two cims or a cim/minicim combo per module is the new metagame. You need those to go higher than 18fps, and it's useful for lower speeds.
In any case, what were you going to use them for, it not for drive? With the abundancy of motors these days, there's no point in not doing it...

There is a point of over kill and i think this might reach it...

[Electronica1]

Now you just need a pto for each module. Might as well get as much use as possible out of all those motors.

[Dunngeon]

Originally Posted by Tyler2517

There is a point of over kill and i think this might reach it...

I think it might barely reach it, just a tiny bit.......

Originally Posted by asid61

In any case, what were you going to use them for, it not for drive? With the abundancy of motors these days, there's no point in not doing it...

Except the loss of all 40amp circuits, that's kinda a big deal.


All in all though, this lightweight packaging is a pretty sweet deal. I've really liked the iterations I've seen in the last few days. Too bad we won't see this module at Bunnybot

[asid61]

Originally Posted by Dunngeon

I think it might barely reach it, just a tiny bit.......



Except the loss of all 40amp circuits, that's kinda a big deal.


All in all though, this lightweight packaging is a pretty sweet deal. I've really liked the iterations I've seen in the last few days. Too bad we won't see this module at Bunnybot

True, you can't exactly just add more circuits. Even so, I still don't see the need for every motor we're allotted. It really does depend on the game, but a lot can be done with pneumatics (254's robot this year had tons and tons of pneumatic cylinders and locks instead of just motors) if you are short on motors.

Also, 1 2/3 cims per module is just a tiny bit more powerful than a 6-cim drive. If you want acceleration in a swerve drive, you can either have a multiple of 3 modules or you can go cim/minicim. I prefer the latter for a multitude of reasons. Think of it: not only can you snake and translate, but you can do it at 20fps and save momentum. The possiblities are amazing!

Now a PTO for this would be the next step... Maybe #25 chains under the chassis, to use the turning motors to climb or something?

[Bryce2471]

Originally Posted by Dunngeon

I think it might barely reach it, just a tiny bit.......

I actually agree, in most cases. For most games I would prefer the 5.4 lb, single speed, single motor module I posted earlier. If the situaltion comes again where mobility is almost everything, this would be awesome.

All in all though, this lightweight packaging is a pretty sweet deal. I've really liked the iterations I've seen in the last few days. Too bad we won't see this module at Bunnybot

Thank you! I wish we could field this at bunnybot as well...
Unfortunately, the money and resources to do that just aren't there this year.

Originally Posted by asid61

True, you can't exactly just add more circuits. Even so, I still don't see the need for every motor we're allotted. It really does depend on the game, but a lot can be done with pneumatics (254's robot this year had tons and tons of pneumatic cylinders and locks instead of just motors) if you are short on motors.

Good point. I think their robot only used four small motors outside of their drive base. That's few enough that they could have used this drive.

Also, 1 2/3 cims per module is just a tiny bit more powerful than a 6-cim drive. If you want acceleration in a swerve drive, you can either have a multiple of 3 modules or you can go cim/minicim. I prefer the latter for a multitude of reasons. Think of it: not only can you snake and translate, but you can do it at 20fps and save momentum. The possiblities are amazing.

or you could do this:

[asid61]

Originally Posted by Bryce2471

or you could do this:

Not if you want a full-featured swerve. The cim in the middle will limit what kind of snake turns you can make. Each wheel in the swerve has to be able to rotate and speed up fully independently.
For crab drive, you can indeed chain them together.

[Bryce2471]

Originally Posted by asid61

Not if you want a full-featured swerve. The cim in the middle will limit what kind of snake turns you can make. Each wheel in the swerve has to be able to rotate and speed up fully independently.
For crab drive, you can indeed chain them together.

With good code, a rectangular robot, and 6 CIMs of torque; I think you would be able to do any swerve movement with a little scrubbing.