Adam Wolf, an engineer at Wireless Design Services by day, electronics maker and creator by night, received a request to build a light show for an upcoming Doomtree concert. Dessa, a singer and rapper in Doomtree, wanted to create something ‘beautiful and spooky’– the main source of inspiration being a scene from the Little Mermaid. The hope was to create glowing lights in the singers’ mouths and on their clothing that could dim and brighten with the music.
First order of business was to a find a way to get the singers’ mouths to glow.
As you might expect, the mouth isn’t the greatest environment for a circuit, so some clever engineering was required. The circuit had to be enclosed in mouth-safe plastic to ensure any saliva wouldn’t close the circuit.
For control of the lights, Adam used magnets as a way to regulate voltage, so each singer is able to turn the mouthpiece on by bringing a magnet up to her face. A lot work went into this little device, it even required a trip to the dentist to create a well-fitting mouth piece!
The lights on each of the singers’ sternums is where XBee comes in. Each LED module was connected to a MOSFET, which was connected to the PWM pin on an XBee Series 1. This setup allowed Doomtree’s light guy, Arlo, to control the lights’ voltage over a wireless link. Above is a picture of the control interface. By adjusting the knob on the top of the control box Arlo is able to adjust the brightness of the lights to match the music.
Below is a short clip of the LED lights in action.