The Big Round CubatronTM
The BRC v2.0 is the world's largest 3-dimensional full color dynamic
light sculpture. It is an array of lights 40 feet in diameter and
10 feet high. It consists of 28 spokes, each of which is 24
lights wide by 10 lights high. Each light is independently
controllable to display any color and brightness level and the entire
display can be updated 50 times per second. There are 6720 total
lights (28 * 24 * 10) made of 20,160 LEDs. The BRC was originally
funded by a Burning Man Art Grant.
- The BRC v2.0 was at
Nocturnal Wonderland in downtown Los Angeles, CA, Sept 29, 2007.
- The BRC v2.0 was at Burning Man 2007 with much updated visual effects.
- The BRC was at Horning's Hideout with the String Cheese Incident,
outside of Portland, Oregon, July 26-29, 2007.
- The BRC was on display at the
Coachella Music and Arts Festival, April 27-29, 2007.
- Made its debut at Burning Man 2006, August 28-Sept 3.
searching Flickr for Big Round Cubatron.
Try searching for Cubatron on YouTube
These short clips show some of the effects.
The video quality and colors are poor.
You can also try TV Free Burning Man
and click on video pod 9.01.
The physical structure that holds up the lights consists of two pieces,
a central mast, and a circular wall of poles. The lights are strung
horizontally and from the central mast to the outer posts:
The central mast is a 10 foot 4x4 inch wood pole standing
vertically in the center. It is supported by 1/8" steel cables
that run from the top of the mast to the top of each outer pole.
The poles around the circumference are
1-3/8" diameter pipe and 10 feet high. They are pre-assembled into
14 "squares" along with some 3/4" EMT pipe to keep the squares together
The squares are held to the ground in each
corner by rebar stakes. The tops of the squares are pulled tight
and held down with rope and rebar stakes.
The light string wires are attached to the poles at 10 inch height
intervals using plastic wire ties and paper clips. The bottom string
of lights starts about 3 feet off the ground.
A small viewing tower was located to one side
of the sculpture. It was built from some scaffolding two
tiers high (10 ft), allowing people to view the sculpture from an eye
level of around 15 feet high.
The light strings are based on an improved version of the design used
in the Cubatron Jr. They are a slightly customized version
The controller consists of 5 parallel microcontrollers which read
preprogrammed patterns from SD memory cards and send them
to the lights. The controllers are synchronized over
an rs-485 connection. Each light consists of an RGB LED that can be
set to a 24-bit color value and changed 50 times per second.
The software and effects are written in C and testing is
done using a custom 3-D graphics simulator that runs on a PC.
There are currently about 40 different effects lasting about
a minute each, and the show loops continuously.
The total power required if everything is at maximum brightness
is around 4500W.
A 240v/30A circuit is required to operate the BRC.
This is converted to 10vdc at 400A by 4 power supplies.
At some installations the BRC was solar powered by Energy Efficiency Inc..
An array of panels charges a large battery bank during the
day, and the BRC runs off the 12vdc from the batteries at night.