In the spirit of Gracious Professionalism, I give you: My MultiDrive.

That’s right folks. I had a nice long think time about this, and I decided I shall share my design with everyone here on CD.
Here’s What I plan on uploading:
A 7 Picture set of 3D Concept Images
A 3DS version of the concept model
My descriptive paper (which needs updating)

And I plan to answer any questions you have. I know my design will be criticized, many people will say (That won’t work right…You stole my idea, etc.)
Just so you know I didn’t steal anything (If you DO believe me)
Here’s the “History” of the design:
It started a little bit before Nats of this season. After we had finished our Regional, I began coming up with all sorts of neat little do-dads (see my CopyCat Code, for example)
But I felt like I hadn’t really designed anything in a while.
Well, I looked around to see what people conventionally did for crab drives, and I said I wanted to raise the bar a bit.
Thus, the MultiDrive is born.
This drive functions as a 4 in 1 drive system. The slogan I prefer to use is “Drive on Demand”
Here’s a few things that differ from typical crab drives:
-Only 2 drive motors
-Two sets of wheels Pivot
-Use of Beveled or Miter Gears
-Can instantly switch between 4 different modes of drive
-Has several backup plans in case things break,strip, etc.

Anyway, I’ll re-post here once the pictures/files are uploaded.

I’m looking forward to learning more about your ideas.

The best part about CD is the opportunity to discuss ideas like this, I think. It’s a real eye-opening process for a lot of people and it’s usually quite a bit fun to take the brainstorming of a typical FIRST team and take it a level higher.

The JPEG Concepts can be found here:

The ZIP of Higher quality BMPs, 3DS files, and Documentation are here:

Well, take a while to browse through it, and tell me what you think.

*Originally posted by Sachiel7 *
**That’s right folks. I had a nice long think time about this, and I decided I shall share my design with everyone here on CD.
Anyway, I’ll re-post here once the pictures/files are uploaded. **



:smiley: :smiley: :smiley:

It’s nice to see that you were able to create your own design, I give you an “A” for effort.

A few things to consider though. Namely structural stability of the module and gear alignment. Your housing design doesn’t allow very much room (thickness) for bearings and stability. It looks like your drive shaft is only supported by a single bearing, which is a bad thing when dealing with bevel gears. Between turning and taking hits, that module won’t last very long… You might want a uniform construction for the module frame rather than separate aluminum plates.

A simple search for “crab module” would yield the design the Thunderchickens used last year:

You might be able to learn from thier implementation if you look hard enough. Things are completely different when going from design to reality.

*Originally posted by Sachiel7 *
I’m afraid that some of the (mentors!) on my team are already coming up with ways to “Shoot down” my idea, and I haven’t even gotten it fully out yet!

I doubt the mentors are trying to “shoot down” your idea. There are any number of reasons why it may not be best to go with your particular design, such as complexity, stability, and construction (including tools and materials available to construct it). Simply said, you need to refine it to meet your teams abilities and to make it reliable.

Take a look at the Thunderchicken’s design. The housing is uniformly made from a single block of aluminum, from the looks of it (which adds a lot of strength & stability), which implies that they have advanced milling capabilities. They addressed the issues of how to keep the bearings and sprockets in place. Lastly, they addressed issues of the most critical component, which is supporting the module. These refinements are what make it a successful design.

Don’t rely on others not to critisize your design. A successful design leaves no room to be critisized.

Thanks for some feedback.
Actually I’ve been discussing this in another thread and I’ve redesigned the top to eliminate the top set of beveled gears on each module.
In my original design (v2) there were in fact 3 bearings on the main drive shaft. One in front of the large sprocket, the “bearing block” a 3x3x5" block with a 5/8 shaft cutout down the center, and the “LockBlock” on the end, supporting the ends of the Gear’s Shafts.

Most of this has been refined in the new design, however, and structural integrity has been taken into account. The drive now runs vertically across the chassis.

Anyway, keep the feedback rolling!

New Pic:

Design v3