CPP Provides Wind Expertise for Iconic Public Art.
Halo is a kinetic, wind activated sculpture located in the Central Park Urban Village Development in Sydney, Australia. Jennifer Turpin and Michaelie Crawford of Turpin & Crawford Studio designed the sculpture to be a collaboration with nature by responding to the kinetic energy of the wind. The sculpture has a 13 meter high mast leaning at an angle, a 6 meter long cantilevered arm attached to the mast, and a 12 meter diameter carbon fiber ring that pivots upon the arm. The arm and the ring (the halo) rotate on a tilted axis in response to the wind. The seamless rotation moves fluidly and serves to provide observers with a sense of calm and peace amidst the busy environment in the park.
While the sculpture moves effortlessly in gentle breezes and fluently withstands extremely high winds, it was not necessarily a smooth and effortless creation. The formation of the sculpture required a large team of designers and engineers with expertise in carbon, mechanical, wind, and structural engineering. The project took three years to complete and required extensive research and design variations.
Turpin & Crawford Studio hired CPP to conceptualize how the wind would activate the sculpture and provide wind design advice. CPP created customized software to test the design and also conducted wind tunnel testing to measure the wind climate at the proposed location. CPP considered the impact of surrounding large buildings and the staged construction of future buildings on the site which would affect the wind climate. CPP immediately recognized the length and shape of the arm as being most important to create a neutral wind environment, which was a critical factor to ensure the sculpture would freely rotate as intended.
CPP proposed and tested several designs and eventually made slight changes to the shape and size of the arm, resulting in a structure that effortlessly responds to gentle breezes, gusts, and strong winds. CPP also suggested adding texture to the exterior of the ring and recommended that the sculpture rotate clockwise due to the site location and variance in wind speed.Through CPP’s testing and design advice, as well as the extensive work by other consultants, the designers completed and installed the sculpture in July 2012.