LONDON'S MILLENNIUM bridge will become a musical instrument this week as a series of vibration sensors translates the movement caused by the wind and people walking across it into music.
From Friday, the resulting sound will be continuously piped into Tate Modern's Turbine Hall and nearby Southwark Tube station.
The project was conceived by sound artist Bill Fontana in close collaboration with Arup, the bridge's engineers.
Arup picked the most harmonic points on the structure to locate the sensors.
Four sensors will be located on the tension wires on the bridge's balustrade and another four on the main suspension cables.
The bridge is most famous for swaying as pedestrians walked over it for the fi rst time six years ago (NCE 15 June 2000).
It has since been fitted with dampers to control overall horizontal movement. These will not affect the localised vibrations picked up by the sensors, said Arup Acoustics associate director Richard Greer.
'We're talking about vibrations which are unsusceptible to people, but which naturally occur in urban environments, ' he said.
As wind blows across the wires, vortex shedding distorts the wind fl w, which can be translated into sound. Greer describes the sound produced as similar to a stringed instrument but with 'ethereal qualities', punctuated by people's footsteps.
The 'sound sculpture' will be known as the Harmonic Bridge and will performing until 16 July 2006.