Cool Frame Ideas?

[Qbranch]

Originally Posted by Hachiban VIII

I've always wanted to build a robot that way. I <3 Fiber Glass

1024 has used fiberglass in numerous applications for guarding fragile components...

Maybe the best and most visible use was to guard our camera in our 2006 robot. One of our members was also on the football team that year and brough his helmet in... which he sat on the top of the robot over the camera. I looked at it... yes it worked but... then i picked up the helmet... well lets say we could have had an extra frame rail in the robot.

But I digress. Yes, I agree with fiberglass being a spectacular robot material. It's easy to work with and requires a tiny amount of equipment to do well, none of which is costly. It's also easily repairable (west systems makes a great repair kit which can be bought in bulk if you plan on using fiberglass a lot, a hefty investment at first but well worth it + lasts you through a lot of holes/cracks).

1024 will eventually try experimenting with carbon fiber... as soon as we get someone to donate/get cheaply a large industrial oven.

Our 2006 robot was probably one of my favorite frames ever... it was simple but it worked. The cool thing was the frame rails (machined out of 1/2" thick 6061-T6 post-consumer aluminum) also had the bearing nests in them for the tracks, and the end of the frame had a tongue-and-groove section to allow for track tensioning (the last part of the frame was a seperate part that slid into it). The two frame rails were joined by a 1/16th inch thick aluminum sheet metal box that was riveted to both sides. Held together great through a season of slamming into the ramps at the last second... man I loved the 2006 game.

-q

[AndyB]

Anything from 1501 is pretty much a sweet frame design whether it be monocoque like previous years or their sweet chromoly design this year.

[Doug G]

Originally Posted by Hachiban VIII

I don't know about these ovens you speak of.
-q

I was referring to what Qbranch mentioned...

Originally Posted by Qbranch

1024 will eventually try experimenting with carbon fiber... as soon as we get someone to donate/get cheaply a large industrial oven.
-q

While in industry, autoclaves and ovens are often used, you can still get a good cure from building your own hot box.

Originally Posted by Hachiban VIII

2005 Our entire arm was made from honeycomb laminated carbon fiber that was resined together at the joints.
-q

That's the kinda thing that would be interesting to make. Do you have any pictures?

[=Martin=Taylor=]

Originally Posted by Doug G

That's the kinda thing that would be interesting to make. Do you have any pictures?

Search before you post I got this picture off of your own team's website!

[Doug G]

Originally Posted by Hachiban VIII

Get a piece of foam, carve it into the right shape. Add some spruce spars for extra structural suport. Cover it with fiber-glass or carbon-fiber, resin the whole thing and cover it with seran wrap to get it nice and smooth.

Then peil off the seran wrap an you'll have a nice smooth, strong, and earodynamic frame. And depending how well you squeeze out the excess resin - light too.

I've always wanted to build a robot that way. I <3 Fiber Glass

We may try some more composite work this year. Last year we learned how to do some basic layups and such, but it would be really cool to build an arm or more interesting mechanism out of carbon fiber rather than a square ramp, which rarely got used. Unlike what someone said, you don't need a large oven, you can build a simple one with just heat lamps. You just need to get the temp up to around 100 or so. Last year we turned a tool closet into a "hot box" to cure our ramps.

[Blue_Mist]

In past three years, our team has welded together an aluminum frame (hot metal, flying sparks, random passerby blinded over the shield at 8:30pm, what's not to love?). Last year, we had it professionally done when we realized something was wrong with our MIG, and our team spent more time fixing it than actually welding. Usually the students weld... This type of frame is sturdy, bottom-heavy and we can always include our traditional 10-degree wedge, but can cause difficulties in adjusting or repairing the drive train. This year, we're going to try to design a frame that is just as sturdy but doesn't require extreme flexibility in the hands or a robot tipping to fix the drive train.

[=Martin=Taylor=]

Originally Posted by Doug G

We may try some more composite work this year. Last year we learned how to do some basic layups and such, but it would be really cool to build an arm or more interesting mechanism out of carbon fiber rather than a square ramp, which rarely got used. Unlike what someone said, you don't need a large oven, you can build a simple one with just heat lamps. You just need to get the temp up to around 100 or so. Last year we turned a tool closet into a "hot box" to cure our ramps.

I don't know about these ovens you speak of.

Team 100 has used carbon fiber many times in the past. Usually we've just connected the pieces with resin and fiberglass.

-1995 We built our drivetrain out of a single piece of laminated carbon fiber with holes cut for wheels.

-2005 Our entire arm was made from honeycomb laminated carbon fiber that was resined together at the joints.

-2006 Our electronics board was made from honeycomb carbon fiber.

-2007 The v.2 "Head" (our manipulator) was made from a combination of wood and fiberglass with reinforced carbon fiber edges.

I'm personally not a big fan of the stuff. It takes special drill bits and saws to cut. And the edges are razor sharp, and can easily cut through wires and flesh !

But if you're still interested in using it check out your local Tap Plastics, or The Robot Market Place. I know in the past it has always been donated to us by Battlebots builders.

I tried to get a local bike shop to sponsor us last year and build our frame out of carbon fiber (using the same techniques they use to make custom bikes). But they were neither enthusiastic nor happy about spending thousands of dollars on us So it fell through...

[Tristan Lall]

Originally Posted by Binome

Bosch Extrusion
Its really nice, and reusable between years.

You probably don't want to hear this, but I'll bring it up anyway....

Based upon past years' rules, and the ways that they've typically been interpreted, only the most trivially modified extrusions are actually reusable under the rules. Basically, for a part to be reusable from year to year, it needs to be COTS and unmodified. In the case of extrusions, while the different kinds of custom cuts that are possible make interpretation of the rule a little fuzzy, things like milled slots or bolt patterns are almost certainly going to be ruled as non-COTS, and therefore not legal for next year's robot. So be careful what you reuse!

Originally Posted by dtengineering

If you can't TIG or MIG in-house, then keep in mind that somewhere in your community there is someone who wants to weld your robot for you. People who like welding tend to like welding cool things, and competitive robots are generally regarded as a pretty cool thing. Perhaps a local community college or trade school can help you out.

That's exactly what 188 tried one year (2006). We ended up with a very unconventional welded sheet metal frame. We also had a few too many crazy robot issues happening simultaneously, and nothing on that robot really got fine-tuned very well. Despite that, I'd like to see more of that sort of semi-monocoque aluminum frame—not because it's necessarily the most effective, but because it's an interesting engineering challenge. In the case of the 2006 robot, 188 recruited the services of a local engineering and fabrication company, but the community college suggestion is an excellent one. (As a matter of fact, for teams in Southwestern Ontario, there's a nice welding lab at Conestoga College in Guelph that might be worth talking to—I can supply contact details if anyone's interested.)

One last thing about welding aluminum: by virtue of the way aluminum heat-treatment works, fusion welding (i.e. when metal melts) almost invariably results in a weld that is weaker than the base metal. So even though you might be welding 6061-T6 extrusions, you might have to use a welding rod that deposits 4043-O filler metal* (which is far weaker). There's one thing that would be even more impressive than trying the fully-welded chassis: building a frame jig which would hold the entire frame rigidly while you heat-treated it in a large oven, back to a high-strength T6 condition.

*More precisely, it's actually -F with properties equivalent to -O, because it wasn't deliberately annealed, rather it just came out that way.

[hipsterjr]

Originally Posted by Binome

Bosch Extrusion
Its really nice, and reusable between years.

2007 was the first time 342 didn't use a extruded aluminum (FMS) frame and we won the Palmetto regional for the first time after competing for 7 years (couldn't have done it without 1319). FMS is useful, but a major pain in the butt. Our whole pit and transporter are made from FMS and we constantly have to tighten stubborn bolts.

[camtunkpa]

222 has a prototype bot to play the 07 game built from 80/20 quick frame and 1/16" lexan. The quick frame is basically 1" aluminum square stock with .060" wall. The connectors used to assemble the frame are made out of nylon. The prototype bot is going to its second competition this weekend(we won BE 6 last weekend thanks to our partners 1626,25 and 1923 for picking us) . It's been through one competition and so far so good. I will be writing up some more detailed information on this frame when we disassemble and check for stress on the nylon joints. So far we're convinced the 80/20 quick frame makes a good, strong, light, and easy to assemble frame. I will post more information as soon as I can.

[Madison]

Originally Posted by camtunkpa

222 has a prototype bot to play the 07 game built from 80/20 quick frame and 1/16" lexan. The quick frame is basically 1" aluminum square stock with .060" wall. The connectors used to assemble the frame are made out of nylon. The prototype bot is going to its second competition this weekend(we won BE 6 last weekend thanks to our partners 1626,25 and 1923 for picking us) . It's been through one competition and so far so good. I will be writing up some more detailed information on this frame when we disassemble and check for stress on the nylon joints. So far we're convinced the 80/20 quick frame makes a good, strong, light, and easy to assemble frame. I will post more information as soon as I can.

Would you mind sharing from where you're getting the nylon connectors? I've been investigating using something like those recently and haven't found very many sources for them. I'm trying to get an idea for what's available, at what cost, and what the lead times are like for getting them delivered.

Thanks if you can help

[lukevanoort]

Originally Posted by M. Krass

Would you mind sharing from where you're getting the nylon connectors? I've been investigating using something like those recently and haven't found very many sources for them. I'm trying to get an idea for what's available, at what cost, and what the lead times are like for getting them delivered.

Thanks if you can help

Your local 80/20 distributor should have them. The tube is $0.13 an inch (it is a special square extrusion with ridges on the inside of the tube, which I assume increase the strength of the connection) and the connector price varies depending on which one you get (straight through, t connection, 6-way, etc), but they all are between $2 and $3 each. My copy of the 80/20 price list is from last March so prices may have changed a tad, but these numbers should be pretty close.

[Madison]

Originally Posted by lukevanoort

Your local 80/20 distributor should have them. The tube is $0.13 an inch (it is a special square extrusion with ridges on the inside of the tube, which I assume increase the strength of the connection) and the connector price varies depending on which one you get (straight through, t connection, 6-way, etc), but they all are between $2 and $3 each. My copy of the 80/20 price list is from last March so prices may have changed a tad, but these numbers should be pretty close.

I didn't even think that it would be produced by the same folks that market the T-slot extrusion. Thanks.

Has anyone used these connectors with more conventional 1x1x.0625" tubing? I'd rather not need special tubing when I've got a local supplier for metal stock and a few dozen feet sitting in the workshop already.

[camtunkpa]

Originally Posted by M. Krass

I didn't even think that it would be produced by the same folks that market the T-slot extrusion. Thanks.

Has anyone used these connectors with more conventional 1x1x.0625" tubing? I'd rather not need special tubing when I've got a local supplier for metal stock and a few dozen feet sitting in the workshop already.

You might want to check with someone on 1089 I know they use the connectors, but I think they are using standard aluminum. I will caution you though, the 80/20 tubing is ribbed on the inside to grip the nylon connectors better. Also I've been using http://stores.ebay.com/8020-Inc-Gara...Q3amesstQQtZkm

this store on Ebay. They have a pretty decent turn around time most parts ship in a day or two and you can generally find parts cheaper through them.

[ChuckDickerson]

Originally Posted by M. Krass

I didn't even think that it would be produced by the same folks that market the T-slot extrusion. Thanks.

Has anyone used these connectors with more conventional 1x1x.0625" tubing? I'd rather not need special tubing when I've got a local supplier for metal stock and a few dozen feet sitting in the workshop already.

Madison et al.

We have used 80/20 QuickFrame extensively for the last two years. We haven't used it for the chassis but for most all of the other structural components. It is really great stuff and easy to work with. All you need is a miter saw and a rubber mallet. If you want to take it apart heat the aluminum near the connector with a propane torch to expand the aluminun just a little and then the connector will usually slide right out to be reused. The only downside is the plastic connectors aren't exactly light and can start to add up if you are trying to squeze out that extra pound or two of weight budget. We bought a bunch of stock and connectors in 2006 and will probably need to restock some this year. I don't know where everyone else buys their 80/20 material but we went through our regional distributor and they gave us quite a nice educational discount. IIRC it was something like 40% and I was under the impression this was the standard 80/20 discount for all FIRST teams.

As far as using the connectors with standard 1" thin walled square tubing I really don't think it will work. The 1" square 80/20 QuickFrame tubing is specially fitted for the connectors. It has longitudinal ribbing inside that forms a friction lock with the plastic connectors. This is sort of the secret to the whole system. The internal dimensions of the QuickFrame tubing is slightly smaller (thicker walled than standard 1" thin wall box tubing) so if you try to insert a QuickFrame connector into standard 1" thin walled box tubing the connector will just fall out (too loose). The tubing isn't really that expensive though. IIRC the standard 1" QuickFrame box tubing was about $10-$11 per 12 foot (145") piece after the discount. They also have tubing with flanges on the side in different arrangements for putting panels in, etc. We purchased some but didn't really use the flanges much and often just cut them off to save weight.

One trick we found was to drill a hole in the end of the tube through into the connector and put a pop rivet in on any connectors you REALLY don't want to back out. This trick is rarely needed but is cheap (and light) insurance.

There are also 80/20 "transition" connectors available to use QuickFrame in combination with 1010 series where needed.

Search CD media photos for our team number "456" and there are 4 photos, 2 of our 06 and 2 of our 07 (1 lifting our 06) robot showing lots of use of 80/20 QuickFrame.

Oh yeah, we have used the KitBot frame for the last two years but the QuickFrame matches perfectly to the 1/4" 1" spaced hole pattern of the KitBot frame if you use the little base connector (part number 9140(gray) or 9240 (black)).

Hope this helps. Any more questions just ask.

Edit: I forgot the mention that 80/20 QuickFrame isn't really made by 80/20 but rather by Esto.