pic: Bit Buckets 2015 Prototype Drive Pod

Cut this today.

11:70 gear ratio, 4" omni wheel.

Will be mounted in our plywood chassis.

For more information, see engineering journal here.

Nifty! I like the single reduction and the angled module approach you’re taking. Needs more Shellac. And mind that ground clearance.

I’m also really jealous of your laser cutter… that’s got to be one of the most useful tools you could have for a 6 week build season.

+1 on the laser cutter. How long does it even take you to cut out your chassis? It’s crazy how fast you guys can get stuff done with that thing.

Our off-season chassis took about 4 hours of laser time, including setup. This module took 9 minutes.

It’s a pretty neat tool to have; we can make 2D parts faster than literally any other team.

Edit: At least as fast as any other team.

Well, that is assuming no one else has access to a laser cutter.
Cough Cough

we just have to assume that no one else does, because we only see 4183 posting pics of all these neat parts



Honestly because we have one now working without one would be extremely hard, if you have a lot of extra money (ha a first team with extra money) I suggest getting one, they are useful in most situations and cut time in design, fabrication, and programming by quite a bit.

Thats a neat looking encoder. Do you have any experience with it that you can share?

This year is our first time using them, but there’s some information here.

Thisis the model we’re using; I believe they’re also available in FIRST Choice.

1899 makes almost fully-wood robots every year.

That kind of speed makes me want to abandon our bridgeport and buy a laser cutter.
But the team probably wouldn’t have the heart.

Why geared so fast?

Why not both? Never give up the mill…

I would take the mill home. :stuck_out_tongue:
We might get rid of our old Grizzly lathe in favor of something that can actually cut steel in a few months, so a hobby machine might be coming my way already…

I remember reading your laser cutter is 29x17", but how powerful is it?

We’re using Killough drive, so robot speed is 1/sqrt(2) wheel speed. We also like the simplicity of a single reduction gearbox.

I’m not certain; I think 60 or 75 W.

Neat drive module. I like the single reduction, very simple. What sort of fasteners are you using to tie everything together?

Does a 4’x8’ CNC plasma cutter count? Each of these parts took 4-5 minutes of cut time (1/4in 6061 T6), and that long cut time is due to the dozens of pierces for the lightening pattern.


The side-panels took less than 2 min each to cut from 0.032 5052 Al.


Or a 4’x4’ CNC router? All of these parts together took about 17min of cut time, most of which was in the pocketing.


Exactly what wood are you burning with your laser. I say exactly because I have access to a 160 watt laser and have tried cutting 1/4 Baltic birch and if it will cut depends on where I get it.
Some cuts real nice and some will only seem to cut to the glue line then just starts burning. So, if you have any details on what you are using it would be appreciated.

I think a killough actually has a root2 speed up.

I hadn’t put much thought into it, but I believe you are correct. Those modules will probably need another reduction stage.


Some plywoods have glues or fillers that don’t cut well, which would explain it. 160W is otherwise overkill for 1/4" plywood.