Burning Man 2013 Honorarium Project / Impossible Triangle Now Made Possible

Lighting Hardware

In the Kickstarter video, Blake (Hooch) mentioned that the Penrose Triangle would be lit by individually addressable color changing LEDs. This facet of the lighting will aid in creating some interesting visuals, not the least of which is creating effects that will bring out the illusion of an actual penrose triangle. This lighting set up creates a whole host of electrical and computational challenges. While the Blakes have been handling the structural set up of the sculpture, an entire electrical design/hardware team has been keeping pretty busy. The set up of these lights is such that it requires a lot of custom wiring and circuit boards to get going. Here are three renderings of just one of the types of circuit boards being made:


I stopped by the Artisan’s Asylum the other night to check in on Jacob and Dewb as they started laying out all of the lights and building these circuit boards now that they’ve been manufactured and delivered. Here’s one side of one of these boards:


It’s worth mentioning that these boards are only about one and three quarter inches long and one and a third inches wide. The team has a lot of soldering to do on these boards:


The triangle will be lit by 24 five meter strands of color changing LEDs. When I stopped in, Jacob and Dewb were affixing the strips of LEDs to a single bar. This enables the lighting team to connect the lights and start running their programs while the sculpture itself continues to take shape.


There are 120 meters (nearly 400 feet) lights on this table:


A few comical trips up a shaky ladder type situation and the lights are hung!


Dewb connects one of the strands to test a rudimentary lighting protocol. As you can see, the strips are hanging from a pretty high ceiling but there is still quite a bit more LED strip spooled on that table!


It worked. All hooked up to the computer and it’s time to move on to some more software and wiring configurations. There was a good bit of progress but even at 3AM, there was another detour before breaking for the day.


The Artisan’s Asylum is an invaluable source for the kinds of collaboration that this project needs to succeed. However late at night, there is always a good chance someone with experience will be around to provide some much needed expertise. Here, Drew helps guide Dewb through the design of yet another wiring configuration/PCB board design:


After a lot of discussion about needs and available resources, the guys settled on a strong footing for the next PCB board design. A quick cell phone snapshot of the white board and that’s a wrap for the night.

Taking I-93 to Burning Man

Yesterday, a flatbed arrived with some I-beams for our base.  Although the upper part of the design needed to be made from new materials, we wanted to reclaim materials for the base.  Fortunately, the junkyard around the corner had a few old pieces of I-93 we could use.  They were a little heavier than anticipated, but we are buying them at scrap rates, and we can sell them back if we ever get this thing permanently installed someplace.  Here, Leonid inspects the delivery with glee.

Surly does things with a forklift you wouldn’t imagine.  It’s kind of like his hydraulic left hand.  Once again, Google automatically made made a little ditty of the procedure for attaching a horizontal band saw to one of these with the forklift.

Have you every seen this guy any happier?

When it all goes together, it’s supposed to look something like this:

The cylinders in the vertices will be made from a old welding gas cylinder.


Climbing the Penrose Triangle

The third arm is in place and the structure has been assembled for the first time. It is now a (nearly) freestanding object. You’ll note the stands holding the base of the cubes in this shot. The floor of the shop is not perfect so it still requires some custom stands to secure it while it’s being worked on and actually CLIMBED!


Part of what makes this project interesting for me is the ability to interact the piece in a physical way. I’m pretty excited to be one of the first few people that have gotten to go up and into the Penrose Triangle. It’s a very cool concept and design but there’s only so much you can really get by looking at scale replicas and exploring the 3D models.  You get a real sense of it’s gorgeous lines when you start walking around it for the first time.


Predictably, my first question when I walk into the shop and see it standing is “Can I climb it!?” With the all clear I start going up. It’s amazing to feel the strength and stability of the triangle while being surrounded by such smooth, winding  curves that one doesn’t normally associate with words like “rigid” or “safe.” The multiple foot holds and places to lean provide assurances all the way up.


The cube at the apex of the structure is held by arms coming from both sides. It’s a bit unnerving at first to see one side of the support twist out from under you on one side, but that’s part of the fun. You come to have a quick understanding of the structure by devising climbing strategies along the way.


I really enjoy seeing the way the arms go out in one direction and then wind down and back in towards the cube at the bottom. It has a crazy roller coaster kind of character from certain angles. It appears as though the arm is leading you up, down and around a bend as you follow it’s curves. Very cool to climb up and look around to find those odd Seussian lines.


Having looked at the renderings and the models since the beginning of the project, it’s rewarding to actually get to replicate some view that you could only get from the small scale renderings. A top-down view of the 3D print:


The same view from atop the structure:


As a side note, the precision of Penrose Triangle’s construction is evident all around at every weld and every beam’s curve. That said, nowhere did it come into such focus for me as it did in seeing how close the very top of it is from the ceiling of the shop. That is a tight fit!


So there you have it. The project has reached an important milestone but there is still a lot of work to do. The smooth shape and solid renderings make it easy to forget that it takes a lot of little details and printouts (2D and 3D!) to go from a model to a standing structure. A print out on the floor of the shop laying out beam members: 


So far the team has gone from an object in modeling software to the 8″ 3D print:


Into this 17′ climbable physical THING. Here, Blake and Josh talk about the project’s needs and the welding that needs to take place:


So much welding


That’s it for now. It’s been great watching the progress of the full structure’s build. There’s still a base that needs to be made and lighting and electronics and and and….  The ability to touch, interact or climb art is what sets Burning Man apart from a typical experience with sculpture and art in general. This particular piece is beautiful in it’s own right but the prospect of climbing and observing the Penrose Triangle from all sides is going to be a special experience for anyone who dares scale it. It is very friendly and easy to climb so it will be great to see so many people being able to enjoy that aspect of it as well.

Two Arms

Tonight involved two fork lifts, and lot of “you’re doing it wrong,” 5/8ths flange bolts tossed to the floor over and over, a few ladders, various types of hoists and straps, two scale models of the assembled piece, and sprinkler pipe, improperly installed Romex, at least three different welders, and the ceiling itself coming dangerously close to tragedy.  The water cooler didn’t come out very well at all, and various boxes of different colored fasteners have been scattered into nether regions under desks that are actually immune to magnetism.  Entire piles of I think this belongs to so-and-so have been shuffled so that the true owner can never be identified.

Keep in mind I designed the thing to be just a few inches short of Surly’s ceiling.  I mean, we wanted to make it as big as we could.  That ceiling seemed really far up there.  Pretty cool that Surly can drive a forklift under it, though.  Actually, I have now seen a new kind of forklift art that will keep me up a night for weeks.

Yes, that is a bolt of lightning come straight from your deity of choice to the piece.  Although we appreciate being anointed in plasma, that won’t happen when we close the circuit by adding the third arm.  Also notice the gallon of lacquer thinner with the box of combustibles as a cap.

Standing on a welding table, you can almost see it start to work.

I told Surly that we had to assemble the last arm in place, due to tolerance stack-up and that any errors in length would turn into a problem in all three axes around the piece.  The first thing I did when we got it standing up was to grab the test arm and check the fit.  It was about 1/8th long, which is well well well within the happiest place it could be.

We Have an Arm

Apparently Google thought that it could turn balancing into dancing a jig.  They appear to be right, although it needs a soundtrack.  Proud to be wearing a SpaceClaim shirt, even if I’m filthy!

Surly always the first pass welding.  Dorothy has been filling in some areas and some gaps.  In fact, if you look closely in the above, you can see that beam “1o’=” hasn’t been welded on its underside and there’s a a totally acceptable gap.   In case I didn’t mention it before, our tolerance is +0 / -1/8″.

I’m pretty sure those welds are Surly’s.  They’ll require some finishing, but I’m happy with the coverage.

This Might Actually Work

Things are starting to come together chez Surly.  There’s been a lot of processing on the beams.  Here Amber seems genuinely pleased with the business that 1.5″ roughing mill delivers.

Although Surly has plenty of bench space, Dorothy is more comfortable deburring the plasma cut plates from  the floor:

Here’s how the arm beams work.  Jacob used the wood router at Artisans’ to lay down a template:

We had to outsource the beam bending for this size tubing, but we gave them a template based on the template itself.

Once the corner cubes are placed just where they need to be, the bent arms get fitted:

Notice we took some scrap 3/8ths and made some fixtures to help position the arms on the flanges:

Once the bent arms were in place, we could see if the beams and all the crazy sticker business actually worked.  Here are the beams taped roughly into place:

Surly then adjusted everything to the right vertices and sent me this cell phone photo of it all welded!

Now, another arm and we get to see if it all lines up!  Frankly, it’s a miracle those arms worked out as well as they did.


Credit where Credit is Due

I work for an incredibly cool software start-up, GrabCAD, which makes engineering collaboration tool called Workbench.  Workbench is the center of our design infrastructure, and is the primary way that we collaborate with each other outside of email and shouting over heavy machinery at the shop.

The Penrose Triangle in Workbench

When we started the project, Workbench was in early development and was fairly limited.  Earlier this month, we released is as a commercial product.  As a product manager, using it in the real world and learning from our experiences has been incredibly valuable.  Additionally, the GrabCAD as a company has been incredibly supportive, and company resources such as our 3D printers have helped tremendously.

For those who are interested, I shared my experience using GrabCAD Workbench on this project on the GrabCAD corporate blog.  For anyone who gets excited about design collaboration, I think you will find it an interesting read.

Also, I would like to thank SpaceClaim Corporation, a company I helped found in 2003 and for whom I worked for ten years, who graciously provided me with a license of their incredibly powerful direct modeler after I departed in January.  SpaceClaim is the primary 3D CAD tool used on this project.  Almost all of the CAD shots you see of the project were generated in SpaceClaim.

One of many screen shots from SpaceClaim

For simulation, we relied on the Autodesk stack.  I’ve had early access to Autodesk Fusion 360 since January, and I used its Simulation 360 tools to perform all of the structural analysis.  In addition, I used Autodesk’s free Labs product Falcon to estimate wind loading on the structure.

Simulation results from Autodesk Simulation 360

Although Burning Man fosters a non-commercial atmosphere, the reality is almost everything at Burning Man has an original commercial source.  These companies have let us use their incredible technology at no cost to the project, and this project could not have happened without them.