Systems

Electronics System

The electronics for Simon: Fire Edition are ambitious for an interactive art sculpture.  We separate the components into two primary systems: Controller and Display.  The two components are connected via wireless communication using XBee Series 1 technology, giving us the ability to interact with the art sculpture at (safe) distances of up to 50′.

Display

The Display electronics are:

  • Arduino Mega
  • XBee Series 1 wireless modem
  • 8 isolated relays (DC control)
  • 4 isolated solid state relays (AC control)
  • Custom sound generation circuit
  • Amplified speakers
  • Asco solenoid for the accumulator
  • spark gap generator for the pilot
  • keyed safety lockout for the Asco solenoid for the accumultor
  • momentary button for spark gap generator
  • (future) Asco solenoid for the pilot

Controller

The Controller is a deeply re-purposed original Simon game from Milton Bradley.  The internal components have been replaced with:

  • Arduino Mega
  • XBee Series 1 wireless modem
  • 4x 300 mA LEDs
  • 2300 mAh LiPo battery, charge circuit, booster circuit
  • Custom Arduino shield for LED control

7. Simon copy

 

 

Fire System

Simon: Fire Edition is built according to NFPA 160: Standard for the Use of Flame Effects Before an Audience.  NFPA 58: Liquefied Petroleum Gas Code is also referenced for the supply-side liquid propane, vessel materials, fittings and hoses.

Let’s walk through the system to understand how it works!

  • The supply liquid propane vessel (upper left in the diagram, below) is placed in a large garbage can and jacketed in a water bath.  The tank is lashed and staked down, as it will become buoyant when it’s nearly empty.  Why jacketed in a water bath?  Well, the pressure in the supply tank is directly proportional to the temperature of the liquid propane.  As vapor propane is created, it cools the liquid propane.  We need >100 psig of vapor, so that means maintaining the liquid propane at ~90F.  That’s done by circulating the water bath across a hot water cylinder heater element and returning it to the water bath jacket.
  • From our toasty warm supply vessel, the propane vapor is controlled at <100 psig by a Marshall Excelsior Regulator (adjustable 1-100psig).  Why only up to 100psig?  Well, the downstream pipes are schedule 40 steel, and are rated to 125 psig, so that gives us a safety factor of 25% on the materials.  Additionally, there’s a 1/4 turn cut off valve just after the regulator, which serves as an emergency shutoff for the supply propane.
  • From our main regulator, propane vapor travels to a 40 pound propane tank nestled within the base of the art sculpture.  Propane vapor accumulates in that tank (hence the term “accumulator”) up to the pressure allowed by the main regulator.  From here, a few things happen.
  • A small amount of propane vapor is taken out through a low-pressure Bayou Classic 0-30 psig regulator up to the pilot light.  Why a “Bayou Classic”?  Well, that regulator has very fine control and allow the pilot flame level to be precisely controlled.  There’s an additional 1/4 turn cutoff here, to shut down the pilot light.  The propane travels up to the pilot, which is made of 1/4″ copper tubing wound in a helix with lots of 1/32″ holes drilled in it, wrapped in stainless steel wool, then covered by a steel muffler pipe (also with lots of holes in it).  Essentially, we’ve built a very, very wind-resistant pilot light.
  • Returning to the accumulator, an Asco Solenoid Valve 8210G003 controls the release of the accumulator propane vapor.  This is a beefy, industrial control component, and it works like a (very fast) valve.  Under computer control, the valve can be opened and closed in under a 10th of a second.  Opening the valve allows the propane vapor in the accumulator to rush up into four 1/2″ metal conduits and then past the fire of the pilot light.  The effect can vary, all the way from a a tiny *poof* with a quick open-and-close of the Asco Solenoid to four jets of fire reaching 15′ in the air.

Simon - System Diagram

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