pic: 2 speed ball shifting swerve module

[Bryce2471]

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[Bryce2471]

It is based on this design that I posted here previously:
http://www.chiefdelphi.com/media/photos/40805

[Lil' Lavery]

Hard to tell from this angle, but do you have enough space between the CIM and the ground to properly route the CIM's wires?

[Bryce2471]

I'm not sure what the minimum bend radius is. I left 0.3in of ground clearance, but that can easily be changed.

[nathannfm]

Originally Posted by Bryce2471

I'm not sure what the minimum bend radius is. I left 0.3in of ground clearance, but that can easily be changed.

.3 not including wires? Thats not gonna work, even on a "flat" field there are usually 1/4" bumps.

[Mike Marandola]

Originally Posted by Bryce2471

I'm not sure what the minimum bend radius is. I left 0.3in of ground clearance, but that can easily be changed.

If I am understanding it correctly, the minimum bend radius of AWG 14 wire is 0.3846".

Sources: Here and here

[AdamHeard]

Originally Posted by Bryce2471

I'm not sure what the minimum bend radius is. I left 0.3in of ground clearance, but that can easily be changed.

One of our swerve revs had a similar ground clearance (for 2011).

The wires survived... but had visible wear and slight damage.

I wouldn't recommend such minimal clearance (especially with the CIM so far from the wheel).

[Bryce2471]

Originally Posted by AdamHeard

One of our swerve revs had a similar ground clearance (for 2011).

The wires survived... but had visible wear and slight damage.

I wouldn't recommend such minimal clearance (especially with the CIM so far from the wheel).

Yeah, you're probably right. As I said it's pretty easy to adjust, so I'll jack it up a little. probably closer to 5/8".

[Bryce2471]

I've found a few options for gear ratio.

Quoting free speed and inches per CIM rev:

Current configuration
11.5fps (1.48ipr) in low, 18.3fps (2.36ipr) in high

or
9.15fps (1.18ipr) in low, 14.5fps (1.88ipr) in high

or
10.9fps (1.41ipr) in low, 30.5fps (3.93ipr) in high

Any of these could be adjusted further with the belt on top. Although, I'd like to avoid that if I can, because it would mean that two types of pulley stock would be required. Let me know which one seems more appealing and why.

[asid61]

I would go 18.3fps personally, but more spread would be necessary to make it traction limited. 14.5fps is too low for my tastes.

[Bryce2471]

Originally Posted by asid61

I would go 18.3fps personally, but more spread would be necessary to make it traction limited. 14.5fps is too low for my tastes.

I tend to agree; especially sense those are at free speed and being traction limited is not a major goal of this drive.

[asid61]

Originally Posted by Bryce2471

I tend to agree; especially sense those are at free speed and being traction limited is not a major goal of this drive.

Those are free speed? Then you might even be able to gear higher...

[MrBasse]

How far off the ground is the bottom of the CIM? Any concern for wires dragging or catching on field debris? What is the spread on the gearbox?

What was the weight estimated at? I knew you were shooting for a low number, how'd you end up?

[nathannfm]

Do you have a weight / weight difference from the single speed?

(What is this, the week of swerves? 2015 should be fun )

[Bryce2471]

Originally Posted by nathannfm

Do you have a weight / weight difference from the single speed?

(What is this, the week of swerves? 2015 should be fun )

Sorry, I forgot to post the specs.
6.7lbs including most of the hardware, but not all.
Final ratios ar 3.66 and 5.866 to 1. With 2.7" wheel.
Smallish spread for auto shifting code.
Dimensions 3" wide, 10" tall and 9" long.

The single speed version is about an inch shorter, and should weigh 5.9lbs.