Maria Del Camino, a mutant excavator mated to a 59 El Camino, with the face of Maria from Metropolis

Maria Del Camino is Bruce Tomb's magnificent mutant vehicle. It started out life as the body of a '59 El Camino, and was then riddled with thousands of hand-drilled holes, turning it into a meshwork. On the hood, the holes form a pointillist portrait of Maria from Fritz Lang's Metropolis. The whole thing was then mounted on an armature supported by a hydraulic tracked excavator, giving it the ability to rumble along at an angle, or poised many feet above the tank-treads, or vertically.

Bruce is one of my Burning Man campmates at Liminal Labs, and he brought Maria out again this year, and took her out early in the morning to the deep playa -- the area of the desert well away from the main action -- and used a GPS and the excavator blade to carve and burnish a huge piece of vector art out of the desert surface, with the intention of having it captured by the Google satellite flyover. He plans to make this process fully automated in future years, giving Maria the ability to turn herself into a giant, diesel-powered mutated Etch-a-Sketch.

Bruce has just updated Maria's blog with some beautiful photos and videos from this year's burn, and a report from the burnishing experiment:

The maximum deviation of the GPS unit is stated as 33 feet and can be as accurate as 3 feet. The graphic deviation showing in this satellite photo, is purely me following instructions from the device, setting aside my perceptions and judgement. This makes evident that there are greater inaccuracies than stated, and illustrates the inherent paradox of this civilian down market version of an ultra precise technology developed by and for the military. I would be wary of relying on this particular device alone to keep a boat off the rocks.

The western edge of the drawing is on hard playa almost like asphalt, so the line is very shallow. Here, Maria’s blade mostly burnished the playa. The east west lines were especially dramatic and reflected the lavender light of the sunrise. Photos by Anne Klint will be posted soon to show this, but here with this photo, the lines are virtually illegible. The strongest track is the north/south line on the eastern edge of the square. This was due to both the conditions of the playa and the GPS signal/device. The playa in this area was covered with drifts of dust, 6” deep or more, not unlike snow drifts, very soft, and difficult to traverse, even with Maria’s 18” wide rubber tracks. While driving this particular track the signals were quite different than all the rest, perhaps a product of a slower speed. If the resolution of this image were higher, you would see a very tight, regular, serpentine or sinusoidal line with an amplitude of about 15-20 feet and a period of about 50 feet. The noodles at the corners are me following directions from the device to land on a precise waypoint. As I approached a corner, I would slow down and make minor adjustments as needed, inching along to left, to right, back again, then sitting there for about 15 minutes to let the signal settle down to 0 degrees of travel angle and 0 feet distance from my destination.

Maria Del Camino (Thanks, Bruce!)

(Photos by Anne Klint)


  1. GPS is not nearly as bad as that, if you spend enough money on the receiver.

    I know a guy who does autonomous robot stuff. He competed in the SparkFun make-your-robot-drive-around-our-building-by-itself contest, and won. He used a GPS unit made by Hemisphere that got to within about 6 inches of the true position.

  2. If a GPS is inaccurate, there’s not a lot can be done. 

    If it’s a matter of signal shift, though, one way to get around that is to go to a known point (one of the brass markers the USGS sets in stone for surveyors to use for baselines) and compare the reading on your GPS to the actual point.  It isn’t difficult math to correct for fuzzy signal, and you’ll have a way to check as long as there are brass markers to be found.

    1. That’s called differential GPS, and is commercially available. Surveyors use it. They’d have to have borrowed one from a surveyor, with a promise to not fill its delicate guts with playa dust.

    1. That’s a very interesting set of patterns, but (a) the Google photo in your link is from last year, and (b) it’s outside the perimeter fence, so it’s not a Burning Man creation.

      It must have been created by aliens.

    1. Better for it to be there getting seen and enjoyed, instead of rotting away in someone’s yard as it was most likely doing before being transformed.

  3. Pretty cool, but it seems to me that the GPS was supposed to be a means to an end, not and end in and of itself. i.e. he didn’t set out to create some kind of commentary on GPS units, but rather to create cool designs on the playa that could be seen from space.

    Given that, I wonder why he didn’t just orient using a good compass, and get much truer, more accurate lines.

    I’m guessing that once the means to the end was chosen, it ended up becoming an end into itself. Which I guess is not a bad thing in art.

  4. This is more of a GPS use fail than a GPS system fail. GPS is really, really good at telling you where you are, and determines your heading by where you just were.
    The problem with navigating to a target waypoint like this is that as you get off of track, the GPS will just calculate the shortest path to the target, not correct you back to the track between start and finish. Small deviations can be amplified, and the track will curve to the target, as seen on the North side of the square.
    I’d suggest generating a series of waypoints between each corner point, maybe 10 or so, to keep the errors small, and to ensure that at 10 locations the line is correct. :)
    Or try putting GPS at the front and back, and see if they’re accurate enough to determine the bearing of your vehicle.

  5. I’ve driven airplanes down the taxiway to see if it could be done (with a safety pilot) using a GPS that would now be over 10 years old and was non-WAAS. It worked pretty well; granted it was not a giant excavator with an El Camino on top (where the antenna is mounted and at what orientation could be a factor). Also, we did this over a relatively short and flat distance in FL. But with the proper modern receiver it should be easy to achieve ~2m in practice.

  6. Does “the google satellite” really update a location often enough to make such a thing feasible? My neighborhood goes years without being updated. I know that because obvious details like the car i sold persisted in my driveway for six years.

    1. Burning Man gets more regular updates than most cities because the founders of Google, among many other famous technologists, are avid burners.

  7. We were camped across the street from you at Pandora’s Fixit Shoppe! Maria del Camino is one of my favorite mutants out there, and I was jazzed to be camping right across the road from you all.

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