04-02-2010 23:32

JVN

Re: pic: How It's Made: 148 & 217 Robots

Video at:
http://www.youtube.com/watch?v=LPeA94gEtp0

04-02-2010 23:38

Ross340

Re: pic: How It's Made: 148 & 217 Robots

Very well done guys. Should have expected though... kudos again

04-02-2010 23:39

JVN

Re: pic: How It's Made: 148 & 217 Robots

On Wednesday at 2PM I sent 75 distinct parts (not counting multiples of the same part) to our sheet metal shop. This represents a new record for any team that has built out of our shop.

To fabricate these parts in the quantities we requested the shop will use 18 4'x8' sheets of metal (0.625" thick, 0.090" thick, and 0.125" thick.)

The total run time to laser/punch these parts is approximately 24 hours. Most of this run time will be done during off-hours.

All the parts will be delivered on Friday evening before the Robowrangler's Saturday meeting.

We love having the unconditional support and sponsorship of Innovation First. We love getting "above and beyond" support from the folks over at Metal Solutions. We love having the ability to run our team in a way that focuses on student prototyping and design such that we can spend lots of time thinking, and only a little time building. We are spoiled, and we know it.

I know the 148 students love touring the Metal Solutions facility and learning more about sheet metal. I've had the opportunity to take a few guests through the shop as well (I think Meredith Novak knows more about sheet metal then she EVER wanted to know.) We thought that some people within the community would enjoy learning a bit more about this great manufacturing technique.

Enjoy!
-John

PS - If you ever visit Greenville, TX -- call me up and I'll get you a tour.

04-02-2010 23:44

Joe Johnson

Re: pic: How It's Made: 148 & 217 Robots

I cried! That was beautiful.

Thanks.

Joe J.

04-02-2010 23:46

V_Chip

Re: pic: How It's Made: 148 & 217 Robots

Superb

04-02-2010 23:52

IndySam

Re: pic: How It's Made: 148 & 217 Robots

Kind of hating you guys right now

05-02-2010 00:00

James1902

Re: pic: How It's Made: 148 & 217 Robots

Very well done. Looking forward to the next episode

05-02-2010 00:04

sportzkrazzy

Re: pic: How It's Made: 148 & 217 Robots

Your robots always look like works of art, so beautiful.... and yes I am jealous lol.

05-02-2010 00:07

Karthik

Re: pic: How It's Made: 148 & 217 Robots

This video is amazing!

Team 1114 has been fortunate enough to have the support of Innovation FIRST since 2008, and has been using the sheet metal facilities since 2009. This year we sent 21 distinct parts (I know, we're slackers compared to 148. ) to the Robowranglers on Sunday afternoon. These models were prepped and sent to the sheet metal shop on Monday morning. They arrived at Governor Simcoe SS on Thursday at 5:00 PM. (Even more impressive considering that pesky international border which separates our teams.) The quick turn around and high quality parts are astounding. IFI is definitely the coolest sponsor we have ever had and are immensely thankful for everything they and the folks at Metal Solutions do for us.

Thanks to John and the rest of Robowrangler crew for putting this together. The posted CAD models of Tumbleweed and Tornado, the whitepaper on the Engineering Design Process and this video are shining examples of why John and crew are role models for us all.

P.S. Now this video is what I call a 5 star teaser!

05-02-2010 00:35

Chris is me

Re: pic: How It's Made: 148 & 217 Robots

Thank you. 148 and 217's bent sheet metal parts have inspired me as long as I've been in FRC. I love How It's Made too, so it's pretty much perfect.

Now, as for the picture and teaser stuff... I noticed the part numbers on one thing labeled for the Robowranglers was TC-2010-300-004. TC? ThunderChickens? Why would Robowrangler parts be marked with a TC part number? Twins?

You can also see the "standard" nine sided wheel in the picture.

05-02-2010 01:16

Paul Copioli

Re: pic: How It's Made: 148 & 217 Robots

IFI and MetalSolutions make parts for the ThunderChickens and have been since 2006. For that we are grateful. We send the part files to John and he gets them made. This year, with me actually at IFI, it was much easier to get the ThunderChicken parts made. All the parts have the Robowrangler sheet format as they have a special drawing method for bent parts.

217's part numbering starts with TC-2010 and 148's part numbering starts with RW-2010. This year both teams' parts were manufactured at the same time. As it has been since 2007, 217 and 148 have collaborated. Each year we have some parts that are identical and some that are not. It varies from year to year with some years having more identical parts than others.

As for this year ... well you will just have to wait and see!

As for the video, that was all John and Brandon Martus. Pretty sweet.

05-02-2010 01:27

s_forbes

Re: pic: How It's Made: 148 & 217 Robots

Thank you for the glimpse into your amazing manufacturing facilities!

That has to be an amazing and unique design experience for the students on your team. I would have loved the opportunity to see all of that when I was in high school. There are so many construction possibilities!

05-02-2010 02:32

robodude03

Re: pic: How It's Made: 148 & 217 Robots

It really is amazing to see the work that goes into creating these beautiful machines. Thanks for the preview and I can't wait to see the bots!

I am definitely looking forward to the next video.

05-02-2010 03:25

AustinSchuh

Re: pic: How It's Made: 148 & 217 Robots

I'm curious. Which brand/part number of press in threaded inserts do you use? 971 tried PEM nuts in 08, and came away less than impressed.

Thanks,
Austin Schuh

05-02-2010 04:02

Madison

Re: pic: How It's Made: 148 & 217 Robots

I want to go to there...

The design process is the most fascinating part of FIRST competition, I think, and it's awesome to have facilities available that allow you to devote so much time to teaching design instead. Each year, our students end up with a fantastic education in drilling holes and a less well-rounded course in design. It's frustrating.

05-02-2010 04:14

artdutra04

Re: pic: How It's Made: 148 & 217 Robots

Looking great! Can't wait to see these robots in all their sheet metal glory.

The combination laser/turret punch machine looks amazing. I feel guilty sending any sheet metal parts to our shop that aren't made with straight angles and circular lightening pockets, because I know they'd be sitting there watching the turret punch nibble away forever.

05-02-2010 04:47

Triple B

Re: pic: How It's Made: 148 & 217 Robots

John,
that is awesome
sure wish sheetmetal and I were friends
mike d

05-02-2010 08:22

Chris Hibner

Re: pic: How It's Made: 148 & 217 Robots

Very cool indeed. I was lucky enough to get a tour of the facilities a few years ago. It was really cool to see. I can't wait to get a look at the final products from all of th IFI teams.

05-02-2010 08:30

Chris

Re: pic: How It's Made: 148 & 217 Robots

Looks great Guys!

05-02-2010 10:34

qwertyuiop[]\

Re: pic: How It's Made: 148 & 217 Robots

do with your freshman if the machine automatically deburs all of your metal?

05-02-2010 10:37

Adrienne E.

Re: pic: How It's Made: 148 & 217 Robots

This is what you spent last night doing?? Geez, I really can't miss meetings can I? I hope there's a robot sitting in the shop when I get there tomorrow, if you had time to make this!

JK (mostly) What a great video! An amazing showcase of a very cool process. Thanks for your hard work John and Brandon.

05-02-2010 11:00

coldfusion1279

Re: pic: How It's Made: 148 & 217 Robots

Wow, wouldn't we all love to see the BOM with all this machining and powder coating.

Cool process.

05-02-2010 11:24

Cory

Re: pic: How It's Made: 148 & 217 Robots

Not really. the BOM won't reflect any of those costs, as the services were all donated by a team sponsor.

05-02-2010 11:43

henryBsick

Re: pic: How It's Made: 148 & 217 Robots

Awesome video, great facility.
Thanks guys.

/jealous

05-02-2010 12:27

Jonathan Norris

Re: pic: How It's Made: 148 & 217 Robots

That video is pure awesome, great job with the How It's Made feel to it.

I've always been inspired by your designs and try to learn more about sheet metal fabrication every year. Every team should try and build the highest quality robot with what resources they have, and the sheet metal resources you guys have are likely unparalleled. Keep on producing beautifully designed robots it inspires the rest of us.

I'm interested in hearing more about how your teams are structured more around prototyping design ideas and obviously very detailed CAD work, then the machining and building aspects that most teams spend a majority of their time on.

05-02-2010 12:58

Brandon Holley

Re: pic: How It's Made: 148 & 217 Robots

That seems like an ok way to make a robot. I guess....






Awesome video guys.

05-02-2010 16:23

Kris Verdeyen

Re: pic: How It's Made: 148 & 217 Robots

Thanks for the video, John and Brandon (and 148). I'm going to have to take you up on that tour offer.

Now to find someone with a CNC brake.

05-02-2010 17:42

skimoose

Re: pic: How It's Made: 148 & 217 Robots

I wish FIRST could encourage more manufacturers to step up the way IFI has. I would love to see more students designing parts in CAD or being more active in advanced manufacturing processes. Making parts with hand tools is a useful skill, but being adept at modern design / manufacturing techniques are marketable skills.

Waiting for our sheet metal parts to arrive!

05-02-2010 19:11

coldfusion1279

Re: pic: How It's Made: 148 & 217 Robots

Maybe I should have said "I". I am interested to see how much getting parts custom made from sheet metal, and then powdercoated, would cost realistically, even without labor.

05-02-2010 19:21

sdcantrell56

Re: pic: How It's Made: 148 & 217 Robots

Anything that is bent is most likely 5052 aluminum. 6061 does not bend very well and 7075 does not bend at all.

05-02-2010 19:41

waialua359

Re: pic: How It's Made: 148 & 217 Robots

Now that's what you call a teaser for sure!
How much for a laser cutter? Seriously.

05-02-2010 21:23

Chris Fultz

Re: pic: How It's Made: 148 & 217 Robots

Awesome video. Awesome process. Awesome that you could share it.

Hmmm, Cyber Blue Road trip to IFI for a tour ...

05-02-2010 23:13

James Tonthat

Re: pic: How It's Made: 148 & 217 Robots

I've been up to Greenville myself, then came a second time with a small group of students. They all enjoyed it, it's well worth the 5 hour drive from The Woodlands.

05-02-2010 23:19

Andy L

Re: pic: How It's Made: 148 & 217 Robots

Same

06-02-2010 09:59

Dan Richardson

Re: pic: How It's Made: 148 & 217 Robots

I think you'd be surprised at how little the total would come in at. The only big initial cost being set up. Considering there is very little time in the process for all those parts ( He mentioned ~ 24 hours ) just factor in an average machine shop time, that cost and material costs.. whamoo you have your answer.

Personal example, we used to have our drive train manufactured by a facility that was not well equipped to do sheet metal. ( Multiple CNC cutting centers no water jets or laser .. ) When we would ask for a quote for accounting / sponsorship letter the cost would often come in at 5000+ for around 10 pieces.

Now that we use a sheet metal facility that quote comes in for around 700 total, and we have 1-2 day turn around rather than a week.

On a side note, I am giddy like a school girl to see this video because of how important understanding sheet metal construction can be for Mechanical Design Engineers. I have been consistently inspired by 148 and 217 year in and year out. There competitiveness on
the field and GP off inspired 1902 to use these manufacturing techniques for many years and I think anyone reading this forum should take note.

06-02-2010 15:09

Akash Rastogi

Re: pic: How It's Made: 148 & 217 Robots

John- would it be possible for you to put on a presentation in Atlanta this year, or even a powerpoint presentation up here on CD, detailing your design process in Sheetmetal in Solidworks? This question is also directed to others who use sheet metal fabrication such as 217, 228, 1771, 1477, 1902 and any others I don't know of.

I've been learning the features in SW but I don't know what works or what doesn't in my designs when, hypothetically, I would try to get them manufactured at a fabrication site. Are there limitations using sheet metal during fabrication? What are the advantages? (other than speed of fabrication, weight, duplicates)

Great video, great insight into your process. Thanks to those who can help answer some of my questions.

06-02-2010 15:41

s_forbes

Re: pic: How It's Made: 148 & 217 Robots

I'd also love to hear more about some of the details that need to be considered when dealing with sheet metal design. One of the things I find most perplexing is the tolerances involved with these kind of parts... Some things I've read online mention that large sheet stock (like 4'x8') can vary in thickness as much as .005" (thicker in the middle).

Separately, how tight of tolerances can the machines hold? For example, when bending a c-channel out of 0.125 thick sheet, how much does the outside flange to flange distance vary?

It seems like getting rivet holes to line up would be a nightmare.

06-02-2010 15:47

Akash Rastogi

Re: pic: How It's Made: 148 & 217 Robots

These are the same things I have been wondering. I've heard from some teams that after they made their parts in sheet, the biggest challenge was making everything line up perfectly.

06-02-2010 20:14

sdcantrell56

Re: pic: How It's Made: 148 & 217 Robots

I don't have any specific numbers but I know on our sheet metal parts from last year specifically the shooter which was quite complex every hole lined up perfectly first go round. We are very fortunate to work with a super high precision sheet metal shop so I dont know if this is the usual.

07-02-2010 01:51

JVN

Re: pic: How It's Made: 148 & 217 Robots

I've never had any problems with tolerances. The laser and punch tolerances are great. I had an argument with Paul a few years ago because the "promised" tolerances didn't meet his needs. I reassured him, they always under-promise and over-deliver. We're spoiled working with Metal Solutions.

Bend tolerances vary purely based on the skill of the break programmer and operator. I'm lucky to work with a group of absolute ARTISTS. For a long time I shied away from allowing for any bends to affect gearbox tolerances, but (in a typical role reversal) Paul has proved to me that these guys are getting things so close to nominal so consistently we shouldn't worry about it. For the first time ever 148 will be riveting our gearboxes together and spacing them with flanges instead of threaded standoffs.

When our holes don't line up it is 99% of the time a designer's error. I'm always amazed how smoothly things "drop together." We always get exactly what we ask for (now, whether that is what we actually wanted is another question...)

I've also never heard of thickness variances like you describe, though it is possible I just never notice it.

Hope this answers some of your questions.
-John

07-02-2010 02:08

JVN

Re: pic: How It's Made: 148 & 217 Robots

Hi Akash,
I already have two presentation proposals in for Atlanta this year, so a third may be a bridge too far. I will work on a whitepaper for this off-season, I'll be sure to pester Paul to help me with it (the two of us working on a paper together would be fun... I think.)

The main advantage in using sheet metal for me is the versatility in design. I use it in 2 major ways:

1. Custom "extrusion" type pieces. You'll see a lot of c-channels, hat sections, question mark channels, and angles on 148 robots. These are made exactly the size we want, with all the mounting and lightening patterns already included.

2. Custom "shell" designs. There are years where our entire robot is one giant box section. This allows for some very rigid, very light structures.

The general rule I tell my students is "get your strength from your cross section, not from your material thickness." This means that if you do it right you can get a LOT out of very little material. Now we consider 1/8" to be "thick". I remember back when I was on a team that made their side-plates out of 1/4"! I distinctly remember Raul looking at our robot at Championship in 2004 and shaking his head: "Why so thick? Just add a flange it'll be 10 times as strong!"

Want to get really good at sheet-metal design? Learn the basic things your shop is capable of. Now learn basic strength-of-materials (I took this as a sophomore MechE at Clarkson). Apply the principles you've learned and think outside the box (or welded tube)...

Take a look at the Tumbleweed and Tornado CAD models. You'll see a few of the ways we utilize this awesome manufacturing technique.

Feel free to PM or email me if you have any questions. Shoot me a design, and I'll be happy to tear it apart for you. Keep at it long enough, and you'll be finding all the times I got lazy in my designs...

-John

07-02-2010 12:03

Collin Fultz

Re: pic: How It's Made: 148 & 217 Robots

This video was really cool, but I'm looking forward to next week's episode on pick lists.

07-02-2010 13:02

Paul Copioli

Re: pic: How It's Made: 148 & 217 Robots

Like John said, it is all about the geometry. There are three thicknesses we use: .0625, 0.90, and .125. I try to start with .0625 and only go up in thickness as required. For the last few years, the major differences in the basic sheet metal construction between 148 & 217 have been:

1. 148 used .090 for the drive base and 217 used .0625
2. 148 primarily used 1/4" rivets and some 1/8" rivets and 217 used 5/32" rivets exclusively.
3. 148 used flat plates with standoffs for the gearboxes and 217 used bent metal and rivets.
4. 217 got most of it's lightening from using .0625 with basic holes and trusses and 148 did it with .090 and a specific focus on visually appealing large lightening patterns.

This year, we decided to try each other' styles and mix and match:

1. Both 148 & 217 are using .090 fir the drive base.
2. Both 217 and 148 are primarily using 5/32" rivets, but using 1/4" rivets for main structural attachments and in place where we may need a bolt due to rivet gun access. We found a very inexpensive pneumatic riveter that can do 1/4" rivets with no problem. Each team owns 1.
3. Both teams are using a bent sheet metal gearbox for the drive directly riveted to the drive base. In addition, our other gearboxes are a combination bent meta / standoffs.
4. Both teams are using the 148 style of lightening.

One major difference between the two designs is the choice of fasteners. 148 uses English (where possible) and 217 uses metric (where possible). This posed interesting design challenges to make interface holes to handle English or metric on the few parts that were the same. We standardized on #10-32 (M5) and 1/4"-20 (M6). That has worked out much better than I planned.

I will probably do a joint white paper with John, but it will have to wait until the VEX stuff settles down as John and I are both extremely busy due to VEX's increasing popularity globally.

07-02-2010 13:15

s_forbes

Re: pic: How It's Made: 148 & 217 Robots

Thank you John and Paul for the excellent info. I've been looking at the 148 models in solidworks (well, the tumbleweed model... I'm afraid if I open the 09 bot my computer will melt) to get a better idea of how you go about designing some of these parts. There are some parts in there that I wouldn't have even thought were bendable. Really awesome stuff!

07-02-2010 16:06

Andy L

Re: pic: How It's Made: 148 & 217 Robots

I started with Tornado... bad choice

07-02-2010 16:30

Ricky Q.

Re: pic: How It's Made: 148 & 217 Robots

This video and the info that John and Paul provided are just part of the amazingness that comes with being a part of IFI and the FIRST teams they support. This is a company that truly "gets it" and knows that supporting FIRST and programs like it is key to ensuring the success of younger generations.

There are no words to describe how awesome it is to be on the same team as JVN, Paul, Brandon and the other unsung engineers and students that make the Robowranglers what they are. It provides inspiration, motivation and countless hours of entertainment.

-Ricky

07-02-2010 16:48

Akash Rastogi

Re: pic: How It's Made: 148 & 217 Robots

Thank you very much, John, Paul, and Sean.

07-02-2010 17:19

JVN

Re: pic: How It's Made: 148 & 217 Robots

Pay careful attention to how the parts interact with other parts. Lots of times you can combine individually "wimpy" parts in a way that makes a "not-wimpy" structure.

Try to visualize how the assemblies will respond to applied forces, not just the individual parts.

-John

08-02-2010 09:42

mplanchard

Re: pic: How It's Made: 148 & 217 Robots

John,

Your movie was just beautiful!

I used sheet metal for laboratory robot design for 5 years. It is light weight and accurate. A few tips on the SolidWorks design side for teams:
-Work with your Sheet metal shop to know their K-factor. SolidWorks uses .5 by default - but this is never the case. Material and shop equipment produce different values. Build these values into the initial design.

-Where do you obtain the material required for the Bend? The answer comes from the Sheet metal Flange position option. The four options are: Material Inside, Material Outside, Bend Outside and Bend from Virtual Sharp.
Material Inside: The outside edge of the Flange coincides with the fixed edge of the sheet metal feature. Material Outside: The inside edge of the Flange coincides with the fixed edge of the sheet metal feature. Bend Outside: The Flange is offset by the bend radius. Bend from Virtual Sharp: The Flange maintains the dimension to the original edge and varies the bend material condition to automatically match with the flange's end condition. Save manufacturing cost and reduce setup time.

- A sheet metal manufacturer maintains a turret of standard relief tools for Rectangular and Obround relief. Obtain the dimensions of these tools to utilize in your design.

- Alternate between 3D formed and 2D flat for every additional sheet metal feature you create. The Flatten feature alternates a sheet metal part between the flat state and formed state.

-Use interference detection in your assembly. You can create configurations of you part to test for tolerance stack up. Make certain you can get tools in to fasten hardware.

-When looking at mating pattern of holes - make certain that you are refernencing dimensions from the same edge. There may need to be a left and right version of a part if the holes are off. Marie

08-02-2010 13:02

artdutra04

Re: pic: How It's Made: 148 & 217 Robots

There are a few general rules that "should" be followed: all flanges should be at least 4x the sheet thickness long; all holes should be at least 2x the material thickness away from the edge of bend; if being made on a turret punch sans laser, the minimum hole size is the material thickness; and the material bend radius is generally equal to the material thickness (there are tables of standard bend radii for each thickness of commonly used sheet metal, but consult with your local shop).

Other than what you listed, I'd also add their ability to adapt to really interesting geometry.

Since this is turning into a general sheet metal design thread, and since I know I'm not the only one who learns by seeing photos of things, here's a bunch of photos of various features of how 228 has used sheet metal on our last few robots:

The following sheet metal part was the first one that I ever designed (back in my senior year of high school). It allowed us to have a pivoting arm that bolted to an IFI aluminum sprocket, which enabled us to do drive by scoring in autonomous, while retaining the ability to pick up tubes from the floor. This would have been pretty much impossible with anything but sheet metal construction.



Here's a photo of it mounted on the robot: http://team228.org/media/pictures/view/3000


Another interesting feature is the ability to have square holes. While it's not the best thing on earth for stress concentrations (it's actually pretty much the worst), it can allow you to run square tubing right through the middle of parts. On 228, we only use CNC sheet metal parts where we need critical tolerances; otherwise everything else is made with mostly 1"x1"x1/16" box tubing, 1/16" polycarbonate sheet, or various sizes of aluminum angle. So interfacing with box tubing is a great advantage for us that sheet metal offers.

Here's how we used it on our 2009 robot. The 1/16" box tubing ran through the 1"x1" hole and face mounted to the inner chassis rail with bolts. The material around the outside of the box tubing acted as a corner gusset for the rear chassis rail.



Here's a photo with the box tubing super structure attached: http://team228.org/media/pictures/view/4838


Another great feature that we use a lot (as visible in the above photo), is we have .201 (#10 clearance) holes on .75 spacing along many of the important flanges on the robot. While we do model pretty much everything mechanically important on our robots before we fabricate any parts, there are occasions where we want to move something, modify a part, or add new parts onto the robot (last year, it was traction control omni wheel assemblies). Having all these preset mounting holes makes it very easy to do without without needing a drill.


Tolerances aren't an issue as long as you make it clear to the machine shop in your part drawings the critical features and the necessary tolerances. Like Paul (and now John), we use bent sheet metal gearboxes integrated into our chassis (via direct drive, live axle drive trains). Last year I wasn't brave enough to use rivets for critical features, but I'm open to them in the future (if we buy a pneumatic riveter, and as long as the GDC doesn't have inane FRAME PERIMETER rules that make rivet heads illegal). All center-to-center gear distances have .003 added. Here's a photo from our 2009 robot.

08-02-2010 16:25

engunneer

Re: pic: How It's Made: 148 & 217 Robots

Really excellent thread. Thanks to all above.

I work for a company that makes waterjets, and I'm always happy to show off the parts on our robot, but our robots are bulky and overbuilt compared to these beauties.

I have to say, though, that our 2008 rabbit had a 1 piece frame made of a sheet of 1/4" stainless, and everything just bolted onto it directly. It was one of the simplest robots we'd made, and our first time doing swerve drive. Good thing we weren't worried about weight that year, I think the plate was 28 lbs empty.

designing elegant lightening holes is so much more fun when you have tools like the waterjet or the laser available. A couple of curvy bits really adds to the design, without sacrificing much in strength.

Really impressive design work above. If we had a nice break, I'd love to design stuff like that.

If you can get your hands on it, I'd also recommend the sheet metal tools in Spaceclaim (It's part of the Engineer package). They're lesser known in the 3D cad world, but I've been really impressed with the tools they've made, especially for sheet metal. (for example http://www2.spaceclaim.com/learnmore...Sheetmetal.flv )

08-02-2010 16:27

Andy L

Re: pic: How It's Made: 148 & 217 Robots

this thread is awesome, really sparking an interest in sheet metal for me