Hanging twenty feet above ground, the pendulums slowly swing back and forth (image from Pattern Studio)
This half-pendulum half-harp musical instrument is the creation of New York based interactive design company, Pattern Studio. Dubbed "The Gravity Harp," it was commissioned by Icelandic musician Bjork for her recent Biophilia tour. The innovative device features four robotic pendulums, each housing an eleven string harp. Hanging 20 feet above ground, the pendulums slowly swing back and forth whilst communicating with a control computer using an RS485 network. In order to maintain an even sequence of notes, each pendulum swings 90 degrees out of phase with its neighbor and is controlled by a motor attached at the top.