6 Wheel Drive, Wheel/Drive Assembly

[tiger1dd]

I'm the newbie, and since I'm the only non-college person on the team that can use inventor, I've been assigned to create a six wheel drive. I was wondering where I could maybe get the different parts to the wheel assemblies+dimensions, as well as some different wheel designs, dimensions, and if you could even post any ipt files for me to analyze, that would be great. Sorry I'm asking so much, I just got a big load put on my back.

Thanks in advance!

Take some time to browse the images in CDmedia. Especially search for 6 wheel drives, and check out the West Coast drives for the most minimalist approaches to this. Once you're familiar with what is out there, model every part yourself. Taking shortcuts will get you through a build season, but doing it right can get you a job.

[tiger1dd]

Alright, I found the Cdmedia, where can I find West Coast Drives, inside CDMedia?

Thanks!

[Adam.garcia]

Hello,

Check these websites out! They have a lot of parts already designed in inventor, which you can use.

http://www.firstcadlibrary.com/
http://www.3dcontentcentral.com/part...rue&l evel=10

These will help you get started with designing an actual robot.

If you have any questions, just pm me and I'll be glad to help!

Thanks,
Adam

[tiger1dd]

WOW! Those two links were exactly what I needed. I'll post what I make shortly. Thank both of you guys so much!

[Edoc'sil]

The simplest 6 wheel drive to build is two traction wheels in the middle and omnis on the corners. No issues turning at all, but it can be pushed in a circle if its hit just right. we loved the maneuverability that this drive offered us this year.


Love to see what you come up with.

[dtengineering]

And before you start assuming that you have to make it out of metal...

also search the CD media photos for "wood" and "plywood".

Or fibreglass (particularly what 842 does with it.)

Jason

Originally Posted by dtengineering

And before you start assuming that you have to make it out of metal...

also search the CD media photos for "wood" and "plywood".

Or fibreglass (particularly what 842 does with it.)

Jason

This! Very this! I've been trying to convince a few team members to try a bamboo robot for a few years now...

[Edoc'sil]

How well does the fiberglass hold up? I have used it for other applications and it doesn't see to be robust enough for FIRST, but then again neither does balsa, and I have seen those bots.

[JamesCH95]

McMaster has CAD files of almost everything they sell, so if you find a bearing, bolt, sprocket, or widget that you like in their catalog, go ahead and download it!

[sdcantrell56]

Originally Posted by Edoc'sil

How well does the fiberglass hold up? I have used it for other applications and it doesn't see to be robust enough for FIRST, but then again neither does balsa, and I have seen those bots.

Fiberglass holds up extremely well in a FIRST setting. Im not sure of any team who has used plain balsa for there robot. We use baltic birch plywood and it is incredibly strong and easy to work with

[Chris is me]

Originally Posted by Edoc'sil

How well does the fiberglass hold up? I have used it for other applications and it doesn't see to be robust enough for FIRST, but then again neither does balsa, and I have seen those bots.

Pulturded fiberglass is beastly for FIRST. Main problem is it weighs a lot, but you can be shockingly liberal with lightening and it will still hold strong. 2791 used it this year to make a bumper frame for roughly 7 pounds. It's great because you can machine them in any school wood shop, and pultruded fiberglass already has some convenient flanges for structure. 1726 has used it for a cantilevered dead axle 6wd before and it seemed to work for them; their bases are a little heavy but they don't tip! I might make some pultruded fiberglass CAD now...

In many applications you may prefer bent aluminium though. We replaced a lot of square fiberglass tubing with kitbot c-channel and saved a lot of weight.

[Andrew Schreiber]

Originally Posted by Chris is me

Pulturded fiberglass is beastly for FIRST. Main problem is it weighs a lot, but you can be shockingly liberal with lightening and it will still hold strong. 2791 used it this year to make a bumper frame for roughly 7 pounds. It's great because you can machine them in any school wood shop, and pultruded fiberglass already has some convenient flanges for structure. 1726 has used it for a cantilevered dead axle 6wd before and it seemed to work for them; their bases are a little heavy but they don't tip! I might make some pultruded fiberglass CAD now...

In many applications you may prefer bent aluminium though. We replaced a lot of square fiberglass tubing with kitbot c-channel and saved a lot of weight.

This post raised a very good point. The trend seems to be to make your base as lightweight as possible. The upsides to this are obvious but the major downside is that it may mean your CG is higher in the air. This doesn't mean you want a 90lb drive train but is just meant as a warning to check where your CG will be. A good drive train is only useful when it has wheels on the ground.


Where does 1771 source its baltic birch? Is it a local supplier or is it online? Ive been wanting to price it out to see if some projects would be cheaper using wood. (Plus, they would look nice imho)

[sdcantrell56]

Originally Posted by Andrew Schreiber

Where does 1771 source its baltic birch? Is it a local supplier or is it online? Ive been wanting to price it out to see if some projects would be cheaper using wood. (Plus, they would look nice imho)

It is definitely cheaper than aluminum. We buy it from a local lumber yard and I believe its about $30 for a 5'x5' sheet of 12mm ply. Be sure to get true baltic birch as there is some birch ply that uses softwood for the filler layers.

[JamesCH95]

Originally Posted by Chris is me

Pulturded fiberglass is beastly for FIRST [...] It's great because you can machine them in any school wood shop

I hope you're machining that wet...the dust is terrible for people and machine equipment.