The magical moment was developed by UK’s Stage One Creative Services, which handled the rigging for the show for the show’s contractor, UK-based Jack Morton Public Events.
The company started with a computer animation of the entire ceremony, plus their own 3D computer modelling to work out the sequence, movements and timing.
It took 14 days for a team of six people working 12 hour shifts to produce the programming sequence.
“Then, once we had it right, we downloaded the animation program to the winch control computers and we were ready to go,” said Jim Tinsley, Stage One’s technical director.
The company custom-built towers to support a net on which was strung an 18-strand cable net with 48mm-diameter wire rope that radiated out from a 3t central hub. The company had originally planned to use the roof, but had to change its design.
A total of 72 winches hung from the cable net, each hauling on 8mm steel wire. It also developed its own positional control computer to control all the required movements. The winches had to move at up to 2 m/s in a synchronised pattern. SEW Eurodrive provided 24 30kW, and 48 22kW helical gearmotors to move the winches. All of the motors were equipped with a specially-developed disc brake, also from SEW Eurodrive. The movement was controlled with 72 Movidrive frequency inverters.
The 1.5t (1.65 US ton) capacity winches lifted the first element, the 19t Cycladic head, together. The head broke into eight 1.5t pieces. Inside was the a sculpture of a boy, a Kourous, itself made up of six 900kg pieces. Nested inside the Korous were the final four pieces that made up a classical Greek sculpture. In total there were 18 pieces to control.
Radio remote-controlled releases broke the head and the Kourous sculpture into pieces.
Before the ceremonies, the head was rebuilt six times – including two technical rehearsals, a pre-dress rehearsal and dress rehearsal. Each time the job took 38 person-hours.
The closing ceremonies also used the net to fly 35 aerialists around the stadium.
The supply of rigging gear was almost as big a job.
Barnsley, UK-based Lifting Solutions supplied 25km of 7mm and 8mm-diameter wire rope for the job. According to the company, at one point during fabrication, European supplies of these diameters of wire rope had completely disappeared. Confidentiality agreements prevented employees at the company from talking about the contract, which it had been working on for two years. “It has been a nightmare as we have not even been able to tell our closest friends and family,” said David Nixon, chain and rope division manager.
