The Frame thread

[M.Wong]

Also, if you want, I can send the cad files for a very simple drivetrain and chassis that we put together.

Here is a photo:

[dtengineering]

The simplest, most reliable, easiest to fix and cheapest to build drivetrain we ever built was also our best performer.

It took seven years to get to this point... we used composites, the kitbot (which was pretty good actually), TIG welded aluminum tubing (which was better)...

And my favorite was this one, seen here airborne and with its twin.

Jason

[M.Wong]

Originally Posted by dtengineering

And my favorite was this one, seen here airborne and with its twin.

Jason

I've always wanted to do this. It goes really well with our Frog Green project, but we just haven't had the time or resources to build something like this during the offseason.

[Marc S.]

http://www.simbotics.org/media/videos/presentations

If nothing else, you can build a super easy drivetrain like the one above, that is also "better than 90-95% of teams". Certainly better than the tank drive and very simple.

[sanddrag]

I'm curious what exact belts and pulleys you're using. Looks like it would be for a large supercharger.

[Grim Tuesday]

Originally Posted by Jeffy

Having a moving robot for the first time in week 3 is very good. We haven't had one moving in the last two years until sometime at the beggining of week 4. Your current timeline seems fine to me. Except: Your frame may a bit too complex if it takes a week to cut and weld parts. Spending a few days to achieve a simpler solution can save you days in the future.

For this next part, don't think I am saying any of this is wrong, but they are questions you need to answer:
1. Why shift?
2. Why treads?
3. Why T-slot?
4. Why multiple heights of tubing structure?
5. Live vs Dead axle

These are all questions you have to answer for your team. There is no universal best option. The best way to design and build a drivetrain is the way that works for your team.

Don't get me wrong, we didn't move until week 6. Akoscielski3, none of your images aren't there.

We do have sheet metal capabilities, so I would be interested if any of the team IFI teams could show us how they do their frames, or just any sheet-metal teams.

I wonder if anyone has done carbon fiber, or other "space age" material frames...

[artdutra04]

Originally Posted by Grim Tuesday

We do have sheet metal capabilities, so I would be interested if any of the team IFI teams could show us how they do their frames, or just any sheet-metal teams.

We have two sheet metal machine shop sponsors, and have used sheet metal for our base chassis/drivetrain in 2007, 2009, 2010, and 2011. 2007 and 2011 were 6WD, 2009 was 4WD, and 2010 was independent swerve. Here's some photos of our 2011 drive train:







This drive train was an absolute tank. Everything shown in the top CAD model (chassis, gearboxes, wheels, chain, etc) came out to 37.4 lbs. Each of our 2-speed gearboxes (custom ones made from a la carte AndyMark gears) weighed less than a stock ToughBox, and were geared for speeds of 6 ft/sec and 16 ft/sec at nominal load. The center shaft is direct-driven from the gearbox output, with the end two wheels being powered by 25p roller chain. All shafts are 1/2" 12L14 steel hex, with all shafts being live axle (it's the simplest way to power Colson wheels). Except for the custom sheet metal and COTS AndyMark parts, all other fabricated parts could be made on a manual lathe.

Even without a belly pan, this chassis was extremely rigid and had no noticeable flex. Once assembled during the build season and run through its initial break in period, we haven't touched it. Nothing broke, nothing needed adjusting, nothing needed replacement.

Edit: If you're interested, I've posted the CAD model of our entire 2011 robot to CD-Media.

PROTIP: If you can't get powder-coating, use enamel spray paint. If you properly clean all parts ahead of time (e.g. use acetone) and let the paint cure for at least 24 hours, it's nearly as durable as powder-coating and much cheaper.

[akoscielski3]

Originally Posted by Grim Tuesday

Akoscielski3, none of your images aren't there.

I can't figure out how to get them up ... can you help me

thx

[artdutra04]

Originally Posted by akoscielski3

I can't figure out how to get them up ... can you help me

thx

You are linking to photos on your own hard drive, only you can see those on your own computer. For everyone to see them you need to upload them to an image hosting website (like imgur).

[akoscielski3]

Originally Posted by artdutra04

You are linking to photos on your own hard drive, only you can see those on your own computer. For everyone to see them you need to upload them to an image hosting website (like imgur).

K thx i think i fixed them now! Thanks ... now i know lol

[548swimmer]

Originally Posted by Grim Tuesday

Don't get me wrong, we didn't move until week 6. Akoscielski3, none of your images aren't there.

We do have sheet metal capabilities, so I would be interested if any of the team IFI teams could show us how they do their frames, or just any sheet-metal teams.

I wonder if anyone has done carbon fiber, or other "space age" material frames...

Though not a frame, we were fortunate enough to have a sponsor donate carbon fiber drive shafts for our support structure and arm.

http://www.flickr.com/photos/robosta...7626347607815/