pic: We got bored :)

[Dillon Carey]

[cdm-description=photo]34178[/cdm-description]

[Stephen of REX]

Cool metal work, but what does it do?

[Jared Russell]

I believe it is the world's smallest swerve module.

[Chris is me]

Heard a little about this, pretty much the neatest little swerve that you ever did see... Looks neat to say the least. Smaller than a kit wheel this year.

[BrendanB]

How much does that little thing weigh?

[Dillon Carey]

here's a picture of the other side:
http://photos-a.ak.fbcdn.net/hphotos-ak-snc1/hs196.snc1/6616_101899156487966_100000036466786_60152_1446174 _n.jpg

How much does that little thing weigh?

It weighs about 1lb 5oz.

the Height from the turning sprocket to the bottom of the wheel is about 3 3/8"
(the wheel is 1 5/8" diameter, 1.625:rolleyes: )

[EricH]

What motor does it use to drive?

[Dillon Carey]

What motor does it use to drive?

whatever motor you wanted to connect to the vertical axle, i would guess a cim in most cases.

[NorviewsVeteran]

If you want a digital camera to focus that close, set it to macro (the little flower icon).

Neat design in the sides there

[Big Kid]

extremely neat, I remember our prototype swerve module (never made it to the robot) was like 5x heavier and bulkier, i like the design too really neat

[Dillon Carey]

http://photos-a.ak.fbcdn.net/hphotos-ak-snc1/hs176.snc1/6616_101902056487676_100000036466786_60368_247441_ n.jpg

If you want a digital camera to focus that close, set it to macro (the little flower icon).

thanks for the tip

[daltore]

Any pictures of the innards? Sweet design, I'd love to see that on an FTC robot (if they would allow it along with all the other parts needed).

[Dillon Carey]

http://photos-h.ak.fbcdn.net/hphotos-ak-snc1/hs176.snc1/6616_101902853154263_100000036466786_60431_1912193 _n.jpg

If there aren't limitations on the wheels there shouldn't be any reason not to put this on an frc bot.

[GarrettF2395]

Wow!
I'm always really impressed by your teams quality of components! :D

Two questions for you:
1) From the beginning of the design process, to having a finished product,
how long did it take your team to complete this project? (Just wondering)

2) Do you have an idea of how much load this little guy can take?

[Dillon Carey]

1) From the beginning of the design process, to having a finished product,
how long did it take your team to complete this project? (Just wondering)

Its the off-season so we have been taking it nice and easy, we have probably been working on it for over a month, if you take out design and it probably took 3 days.

In a build season environment we could probably have 4-6 of these done in 3-4 days (give or take a few depending on when the waterjet is open and when we can get the hex put in the bevel gears and axles made).

2) Do you have an idea of how much load this little guy can take?

The wheels would be the weakest point, in my opinion, since everything else is .25" plate and .5" hex.

http://banebots.com/pc/WHB-WS-174/T40P-174BO-HS4 is where we got the wheels, but i can't find a number for how much they can hold, although I'm pretty sure that having 3 wheels per module and having 3-4 modules on a robot that the wheels would be fine.

[Jared Russell]

The only caveat of such small wheels is ground clearance. If next year's game requires climbing a ramp or other obstacle, big wheels become valuable.

[Andrew Schreiber]

The only caveat of such small wheels is ground clearance. If next year's game requires climbing a ramp or other obstacle, big wheels become valuable.

Simswerve... always a good thing to bring up, just because there is an obvious solution does NOT mean it is the only solution. With modules this small and light you can really do some cool stuff.

[AdamHeard]

Simswerve... always a good thing to bring up, just because there is an obvious solution does NOT mean it is the only solution. With modules this small and light you can really do some cool stuff.

On a similar note, for a game like 04; Why even tackle some problems? Hanging from the floor in 2004 was a negligible (1'?) difference in height compared to hanging from the platform. Always double check that a problem is really a problem.

[Greg Needel]

I love this. The FIRST community never ceases to amaze me with their ideas which I probably would never have thought of, this idea is one of them. I can totally picture this on an FRC robot, tucked away inside a 3x3 or 4x4 frame rail. It could be an almost "hidden" drive train as it would take up a very small amount of real estate.

As for the wheels, I have heard mixed reviews about the banebot wheels. Just like any traction devices harder wheels don't provide enough traction and the soft wheels wear too quickly. A unique opportunity you have with a 3 wheel design is a mixture of wheel durometer, while I am not sure you may be able to "tune" your traction using different combinations, the one that strikes me as obvious is high traction on the inside and harder wheels on the outside.

A couple of questions:

Any reason you didn't use gears or even #25 on the outside, I would suspect you could play with the geometry a bit and make gears work making assembly even easier.

Do you think you really need ball bearings in the modules? I think you could get away with oilite bronze bushings to keep the space and weight lower.

Did you think about drilling out the hex shafts to reduce weight? you could probably sink a 1/4 hole through your shafts and loose even more weight.

Overall I really like the idea, and don't be surprised if I borrow some of these ideas for a future robot.

[Aren_Hill]

that is #25 chain.....also those bolts are #6's for size reference

and the bearings are the 1/2" hex bore andymark ones enabling us to use the banebots wheels without custom hubs and not having to make spiffy shafts just buying some 1/2" hex stock and adding snapring grooves

we also have always used bearings in all spots on the drive out of just a nagging feeling bushings hurt efficiency we like the bots flying (not quite 254 but close).

Yeah i suppose we could bore out the shafts it would be quite easy, we'd thought of that and it would probably happen on the final version of a real bot. Also the Hex shaft is 2024 alum.

And we went for the orange wheels for the fact our team colors are orange and black and this one is for proof of concept and show, final we'll play around more

another awesome part about this is you can add 1 reduction between a cim and the input shaft and have a reasonable speed, no weight wasted on extra reduction to get to say a 6" or 8" wheel

Piloted and designed by Dillon i was just a consultant

[NorviewsVeteran]

Any chance of another beauty shot, next to a quarter or ruler or something?

[Akash Rastogi]

I go to visit MIT for one weekend and this is what you do, Aren? :yikes:

Great stuff.

[R.C.]

This is like the coolest thing I've seen all summer. It reminds me of a lego version of a big swerve, not that is not usable. But it fits like one aka the notches and I love it (PUZZLE SWERVE). I second Greg, I may use this idea in the future.

Hats off to you guys for the wicked design.

-RC

[Dillon Carey]

http://photos-g.ak.fbcdn.net/hphotos-ak-snc1/hs196.snc1/6616_101916723152876_100000036466786_60894_6436604 _n.jpg

Any chance of another beauty shot, next to a quarter or ruler or something?

[Greg Needel]

how come the wheels are not centered?

[Dillon Carey]

The wheels aren't centerd because in order to make the module shorter we had to offset the wheels from the bevel gear

[AdamHeard]

WOW. that pic with the quarter totally changed my concept of the scale. that is TINY.

how come the wheels are not centered?

It looks like they might hit the bevel gear if shifted to the left at all.

[Brandon Holley]

Very impressive guys! I have an extremely similar design in development for part of my senior design project. Please keep us up to date on those wheels as your testing. The polypro hubs seem like the big question mark for me. Also, just to confirm...how do you guys hold the vertical miter gear on the shaft? Looks sweet!

Brando

[JesseK]

Very impressive, though I'd worry about wheel tread wear if it's soft rubber.

[Dillon Carey]

The vertical bevel gear is held on by a snap ring.

[EricH]

WOW. that pic with the quarter totally changed my concept of the scale. that is TINY. I gotta agree. I held a quarter up to it... It's just barely larger than life in the picture.

You better let us in on test results on this one...

[AndyB]

Love it, love it, love it.

You should get a shot of the mini next to one of your full size boxes from last year (if you still have an extra one lying around).

Great job.

[M. Mellott]

Really nice job, guys!! Can't wait to see these on a test chassis!!

[Josh Fox]

*double take at picture with quarter*:ahh:

Wow. That's extremely impressive, way to push the creative envelope. I can't wait to see more on this module in the future.

[gallo26]

thats extremely awesome! solving the problem of swerve modules being WAY too heavy!! Very cool!

Now this might be a stupid question, but my team has never worked with modules like this, and I'm hoping to actually get my team into it. But how does the module stay mounted in place? Like, what keeps it in its place and allows it to rotate? some platter bearing? I guess i just don't see it... Thanks in advance for answering that! :)

[Jonathan Norris]

Wow!! that picture with the quarter just freaked me out how small these are... I guess my only concern would be with what they are rotating on seeing how small they are... These wheels are super impressive and have my mind spinning with new ideas...

[hillale]

Wow!! that picture with the quarter just freaked me out how small these are... I guess my only concern would be with what they are rotating on seeing how small they are... These wheels are super impressive and have my mind spinning with new ideas...

I'm pretty sure the current rendering has the lower disk nested in a complementary ring of delrin or the like which is mounted to the frame. Three of our members (including Dillon) are currently on a camping trip. Dillon's mom got a call today letting her know that they're working on designing a drivetrain for next year's game.

[sdcantrell56]

If these wheels dont hold up you could look into making your own tiny wheels and pouring urethane tread on them like 125 did in 08. I think colson makes some pretty tiny wheels as well and they would definitely hold up much better.

[EricH]

Dillon's mom got a call today letting her know that they're working on designing a drivetrain for next year's game.
Would that be the water game, the flying game, or the Martian game?

[Chris is me]

Why would you go camping to design the drive train... wait a second it's a GAME HINT! :yikes:

[Aren_Hill]

These will have a thrust roller bearing at the top that can easily handle the load these'll see, pushing up against a flat plate bolted to the frame, at the bottom a delrin or UMHW right will encircle the disc of the module.

Dillon does have a frame cadded up, but as of now we do not plan on completing a full prototype for money reasons. We will on the other hand be putting this on a setup with an old chassis and 2 casters and seeing how it lasts durability wise at the very least.

[Akash Rastogi]

These will have a thrust roller bearing at the top that can easily handle the load these'll see, pushing up against a flat plate bolted to the frame, at the bottom a delrin or UMHW right will encircle the disc of the module.

Dillon does have a frame cadded up, but as of now we do not plan on completing a full prototype for money reasons. We will on the other hand be putting this on a setup with an old chassis and 2 casters and seeing how it lasts durability wise at the very least.

Have you looked into using Teflon sheets? That stuff is pretty awesome compared to UHMW :rolleyes:

[Aren_Hill]

ahem, If you do use these wheels, never spin them on carpet. The tread kinda leaves in a unelegant fashion (ow).

We'll be pursuing colsons and also the prospect of making our own

[Dillon Carey]

http://photos-h.ak.fbcdn.net/hphotos-ak-snc1/hs176.snc1/6616_102147259796489_100000036466786_67919_4829078 _n.jpg


Not pretty :ahh:

[JesseK]

I'm thinking Baltic Birch wheels with riveted Roughtop tread for production, or whatever wood you can find for prototyping in the meantime. You could make them whatever diameter you wanted to, however wide you wanted to, and it would be one solid wheel.

This also shows the rest of us that the BB wheels probably wouldn't hold up very long in an overall FRC season for a defensive-type bot.

[Brandon Holley]

http://photos-h.ak.fbcdn.net/hphotos-ak-snc1/hs176.snc1/6616_102147259796489_100000036466786_67919_4829078 _n.jpg


Not pretty :ahh:

Can you guys elaborate on your test setup for this??

Thanks
Brando

[Chris is me]

What durometer of polyurethane were you guys using? That looks soft enough that you could just peel it off if you wanted....

[Brandon Holley]

I believe the orange colored urethane from banebots signifies a shore 30A durometer.

//its shore 40A see below

[Aren_Hill]

Can you guys elaborate on your test setup for this??

Thanks
Brando

probably around 80lbs of weight on module, cordless drill powering it

Held the setup still and spun the wheel on carpet seeing how the wheels would handle it
after around 2 seconds stopped and this is the result

[Fe_Will]

"Black PP Core, Medium Orange 40 Shore A TPR Tread" From the BaneBots website.

[sanddrag]

I wonder if the Blue 50 Shore A would do any better. Also, isn't 80 pounds a but much for one module?

[Aren_Hill]

Yeah it is, but even then seeing it die in this fashion convinced us to no longer mess with the banebots wheels.
Kinda a safety factor test and they failed

[Akash Rastogi]

Yeah it is, but even then seeing it die in this fashion convinced us to no longer mess with the banebots wheels.
Kinda a safety factor test and they failed

Which Colson wheel do you plan on trying out?

[Aren_Hill]

2"dia by 7/8" wide colsons

[M. Mellott]

Thanks to all the folks from 1625 for showing everyone these pictures. Each new image brings new and "wonderful" surprises - I love it!!

[Dillon Carey]

http://photos-f.ak.fbcdn.net/hphotos-ak-snc1/hs147.snc1/5454_1226972671865_1155480053_30700893_177272_n.jp g


You should get a shot of the mini next to one of your full size boxes from last year (if you still have an extra one lying around).


Its not last years swerve module, its one of the original prototype tubes.

[Shelabot]

WOW! How practical would that be? Considering the wheels shred easily... How did you guys get the chain length right on?

(From what I can see the 25 chain look pretty taught...)

[EricH]

WOW! How practical would that be? Considering the wheels shred easily... How did you guys get the chain length right on?

(From what I can see the 25 chain look pretty taught...)It's not terribly hard to do if you have CAD. You can find the size of a link pretty easily, giving you a unit that we'll call one link. You find the exact wrap around the sprockets, which gives you a certain distance (x links, we'll call it). Then you find the exact distance between the wraps on both sides and get another distance (y links). Add x and y and you get the number of links needed. If there is a fraction less than 0.5, add a half-link (special link); if there is a fraction between 0.5 and 1.0, add one link. Make your chain that number of links long, put it on, and you shouldn't have to worry about tensioning for a while.

[Dillon Carey]

WOW! How practical would that be? Considering the wheels shred easily...

We are currently working on a different setup incorperating colson wheels http://www.robotmarketplace.com/products/colson_wheels.html. The reason we originally went with the banebots wheels is because they come with a half inch hex in them.

[JesseK]

Any updates? I think it'd be cool to see these orange-anodized ...

[Aren_Hill]

The place nearby us that anodizes stuff cant do orange sadly

[Dillon Carey]

We have been working with colson wheels, and they seem to be doing pretty well.

[Dillon Carey]

I have found a con to small wheels, I lost one...

[Chris is me]

I have found a con to small wheels, I lost one...

Post a picture of the wheel (say, in a module) and I'll help look for it. :P