23-06-2013 20:38

pmangels17

Re: pic: Ball Shifter Swerve 1

That looks pretty cool, don't see too many 2 speed swerves. Out of curiosity, what is the mass of one of these doohickeys?

23-06-2013 21:49

cbale2000

Re: pic: Ball Shifter Swerve 1

Without seeing a side view it's hard to tell, but doesn't this configuration make the CIM motors sit a little close to the ground?

Perhaps mounting the gearbox from the top rather than the bottom would be a slightly safer solution?

23-06-2013 22:00

Peyton Yeung

Re: pic: Ball Shifter Swerve 1

The picture posted seems similar to how 221 manufactures swerve driving pods.

23-06-2013 22:47

orangemoore

Re: pic: Ball Shifter Swerve 1

If I had to guess I would think that the top of the module would be about 10 inches off the ground and the bottom part of the motors would be about 4 inches.

23-06-2013 23:37

Jeffy

Re: pic: Ball Shifter Swerve 1

This is great.

I've had an idea like this sitting in my head for a while. Seems like you could use a kitbot shaped frame and create individual steering pods with one drive box driving two pods.

Any special features?

24-06-2013 16:32

magnets

Re: pic: Ball Shifter Swerve 1

I got the idea after seeing pictures of a robot using those modules. However, the steering system is a mix between what the robonauts did in 07, and what 1640 does now. Also, this version has a mistake, as I took the picture between versions. In the picture, it has a live axle, but the sprocket is bolted to the wheel, and the wheel has bearings. It should not have a bearing on the side plates of the module, and it should be set up for a dead axle configuration instead.

24-06-2013 16:43

Chris is me

Re: pic: Ball Shifter Swerve 1

That's a good change - a structural dead axle (e.g. a tapped standoff) adds some rigidity to the module, right where you want it to be rigid.

How is this module being supported? The bearing setup for that is obscured by the frame rails. This portion is what makes or breaks a lot of swerve drives.

24-06-2013 17:05

magnets

Re: pic: Ball Shifter Swerve 1

Right now, the weight of the robot is supported by a large thrust roller bearing that sits in a little groove in the top plate. On top of the thrust bearing is a huge bearing (yellow, it should be pushed down so that it is against the grey thrust bearing) with an inner diameter that is the same as the steering tube (red). What isn't shown in these drawings is an additional bearing for the rotating module.

I'm not sure if this will work, but I was thinking of making a bushing by putting a piece of large diameter PVC pipe around the module, putting a disc around the module, and then putting a little delrin ring around the disc so that it acts like a bearing. This would be helpful because it would be a large distance away from the other bearings; however, the PVC pipe might not be rigid enough.
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Also, do you think that another set of reinforcing side plates would be useful?
Like in this older version
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Also, the step file for this part is posted at http://www.chiefdelphi.com/forums/sh...35&postcount=3

26-06-2013 10:17

magnets

Re: pic: Ball Shifter Swerve 1

(Sorry if this is a duplicate post. I tried to post two days ago, but it hasn't shown up yet, so I'm trying again.)

Right now, the weight of the robot is supported by a thrust roller bearing from mcmaster. The roller bearing(grey) sits on a groove in the top plate, and and a large bearing (yellow) sits on top (it's been moved up so the grey bearing is visible). The large bearing has the same inner diameter as the steering tube (red) which is welded to the top plate (blue). I think that I need an additional bearing/bushing, and I am considering designing a disc that goes around the rotating part that sits inside of a piece of pvc pipe and has a delrin ring to reduce friction. However I don't know if this will be rigid enough to be effective. I may also look into doing something similar to what is on the wild swerve modules from 221.

[IMG][/IMG]

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