pic: 6 week swerve

[lukedude43]

loading photo ...

Looks nice. How much pre-season testing have you done?

[orangemoore]

Originally Posted by Andrew Lawrence

Looks nice. How much pre-season testing have you done?

If you read what it says it sounds very much like they have no experience.

[lukedude43]

None, programmer made some swerve code for fun and I had been toying around with the idea in the offseason but everything was started fresh on everything when the season started

Out of curiosity (if you don't mind me asking) - what was the thought process behind deciding to choose swerve for the first time in-season this year?

Spoiler for I want everyone moving this season:

Do you wanna build a swerve drive?
That doesn’t move at all
I know that tank drive is a bore
But you won’t score
Stuck up against the wall
It’s best to test pre-season
But you did not
So please ask your-self why!
Do you need to build a swerve drive?
It’s not too late to not do swerve drive.
(please just drive...)

[AustinH]

I wonder if the game this year is at all conducive to taking these sorts of risks. We've been able to spare some individual team members for tackling quite a few of these "don't try this during build season" projects. For some reason, it seems like a more favorable risk/reward scenario compared to previous years in case we don't end up checking off all the boxes.

Looking forward to seeing how this turns out for you guys!

[Christopher149]

Originally Posted by Andrew Lawrence

Out of curiosity (if you don't mind me asking) - what was the thought process behind deciding to choose swerve for the first time in-season this year?

Spoiler for I want everyone moving this season:

Do you wanna build a swerve drive?
That doesn’t move at all
I know that tank drive is a bore
But you won’t score
Stuck up against the wall
It’s best to test pre-season
But you did not
So please ask your-self why!
Do you need to build a swerve drive?
It’s not too late to not do swerve drive.
(please just drive...)

Sorry, but I can't resist:

Spoiler for more lyrics:

Luke, please, I know you're in there
People are asking how the drive has been
They say do tank drive
And I'm trying to
The design is right here for you
Let's just change it...
We only have this one 'bot
Just this one season
What are we going to do?
Do you wanna build a swerve drive?

[lukedude43]

Originally Posted by Andrew Lawrence

Out of curiosity (if you don't mind me asking) - what was the thought process behind deciding to choose swerve for the first time in-season this year?

Spoiler for I want everyone moving this season:

Do you wanna build a swerve drive?
That doesn’t move at all
I know that tank drive is a bore
But you won’t score
Stuck up against the wall
It’s best to test pre-season
But you did not
So please ask your-self why!
Do you need to build a swerve drive?
It’s not too late to not do swerve drive.
(please just drive...)

Like a lot of other people we thought omnidirectional drive would be useful, swerve was best for our method of dropping off stacks of totes, and we honestly just thought it would be fun.

[Navid Shafa]

Originally Posted by Christopher149

Sorry, but I can't resist:

Spoiler for more lyrics:

Luke, please, I know you're in there
People are asking how the drive has been
They say do tank drive
And I'm trying to
The design is right here for you
Let's just change it...
We only have this one 'bot
Just this one season
What are we going to do?
Do you wanna build a swerve drive?

*Looks good Luke, we've got 4030 on our Fantasy FIRST alliance so I'm really hoping you pull it off

[lukedude43]

Originally Posted by Christopher149

Sorry, but I can't resist:

Spoiler for more lyrics:

Luke, please, I know you're in there
People are asking how the drive has been
They say do tank drive
And I'm trying to
The design is right here for you
Let's just change it...
We only have this one 'bot
Just this one season
What are we going to do?
Do you wanna build a swerve drive?

Haha this is beautiful

Something important I forgot to mention is that we have a set day in week 4 where we will consider if we have actually made it to a point where we think our swerve gives us any benefit over a traditional tank drive. When subsystem integration is fully cadded it will include a fully fledged tank drive configuration so if we decide to ditch swerve we should be able to have a running tank a few days later.

[asid61]

If that bottom is a single piece, you will want to add a radius on the inner edges on the top.
How thick is the bottom plate? It looks pretty thin right now.
How are you constrianing the bevel gears on that shaft? How are you constraining the other gears?
Your top plates are too thin. It looks like it's 1/8" at most. Make it 1/4" to be really safe.
I LOL'd at that gear on the top. I assume that's a versakey gear with 3/8" hex bore like I ised on my drill press verson.
You need some thrust bearings on the module to support the vertical loads. This year more than ever it's going to be turning under a lot of load.

All things considered I would not do a swerve drive fresh out of the box. Please consider buying something like a premade team 221 revolution module and just belting some motors to it.

[lukedude43]

Originally Posted by asid61

If that bottom is a single piece, you will want to add a radius on the inner edges on the top.
How thick is the bottom plate? It looks pretty thin right now.
How are you constrianing the bevel gears on that shaft? How are you constraining the other gears?
Your top plates are too thin. It looks like it's 1/8" at most. Make it 1/4" to be really safe.
I LOL'd at that gear on the top. I assume that's a versakey gear with 3/8" hex bore like I ised on my drill press verson.
You need some thrust bearings on the module to support the vertical loads. This year more than ever it's going to be turning under a lot of load.

All things considered I would not do a swerve drive fresh out of the box. Please consider buying something like a premade team 221 revolution module and just belting some motors to it.

Probably should have posted cad cause it would clear up a lot of your questions/considerations but my naming on some parts is embarrassingly bad (I blame sleep deprivation) but this should definitely help http://imgur.com/QfTX6i1

The bottom is being milled out of a single piece of 4x6x.25" 6061 channel

the plates are .125, but this is designed to use the chassis to beef up the outer edges and the gray squares are actually bearing blocks holding 1" ID 2"OD bearings. these are bolted straight through, counterbored on the top bearing block, with nut clearance on the bottom. We think this should be fine for preventing the plates from warping.

I didnt see your drill press swerve but yea it's a 3/8 bore 44 tooth versakey gear. Great minds think alike (and fools seldom differ)

there is a 1" ID thrust bearing and accompanying washers in there.

[nathannfm]

Put your module into the CAD of the field right at the transition between the carpet and the scoring platform. Rotate the module as it would if the steering motor was rotating it, will that low ground clearance gear run into the ramp in any orientation? Looks to me like it will.

[lukedude43]

Originally Posted by nathannfm

Put your module into the CAD of the field right at the transition between the carpet and the scoring platform. Rotate the module as it would if the steering motor was rotating it, will that low ground clearance gear run into the ramp in any orientation? Looks to me like it will.

Thank you for pointing that out, just updated to fix it http://imgur.com/eowq8F1

[asid61]

Originally Posted by nathannfm

Put your module into the CAD of the field right at the transition between the carpet and the scoring platform. Rotate the module as it would if the steering motor was rotating it, will that low ground clearance gear run into the ramp in any orientation? Looks to me like it will.

As long as the wheel is bigger than the gear, it should be hard for it to crash unless the whole robot tips.