- 8500 kg “Troika”
- 1309 meters LED ribbon
- 1700 meters copper power bus
- 2000 meters milled edges
- 140 kg glitter
- 2000 hours engineering and design
- 5400 hours assembling parts
- 40000 viewers in the stadium,
From The New York Times – reporting from the Sochi Opening Ceremony:
“No doubt, one of the most enduring images for the audience was that of the glowing white troika, the chariot drawn by three horses immortalized in Gogol’s novel Dead Souls.”
The three horses of the troika were up to 25 meters long and 20 meters high. They were engineered and manufactured by Visual act AB. Visual act also managed the installation and operation of the troika for the Opening Ceremony in Sochi.
The troika started as a simple sketch by the designer George Tyspin and his team. They also supplied drawings showing the desired shapes of the individual horses and developed a puppet like model to show how the animation might be achieved.
Visual act’s engineers started working in parallel on construction and animation. Objects of this size grow quickly in weight, and each horse was limited to 2800 kg. Together with the lamination provider Diab Group AB, Visual act developed and produced large panels (2.6 x 10 meters) by laminating aluminum coil (plate) to either side of a Divinycell foam core. The panels for the heads were 120 mm thick. The parts of the horse were then milled from the panels on automated machines.
The parts were assembled into larger sections though the use of aluminum plates which were either glued or bolted to either side. Bolted connections would later be removed and reattached once the horses had arrived on site. Holes for the connections were created during the milling process.
An ingenious method of animation was devised, using systems of axes, action rods and belts, to allow all motions to be coordinated by a single axis. The animation was completely developed in Solid Works.
Once the animation was designed the third phase of the engineering could be started. This involved designing the so called “bicycle frames” that would both hold all parts together and carry the horse’s machinery. Each horse would contain 3 servo motors, the largest one handling the head – which required mechanical torque approached 10 000Nm. The legs, although light in weight, were large in size, and the forces on some action rods exceeded 5000N. The bicycle frames became large trusses. Extensive calculations were made to confirm the safety of the engineering.
The horses would gallop at about 3 cycles per minute. This meant that the longer legs were moving at speeds of over 5 meters per second. A hard emergency stop at this speed could be fatal, brake torques were carefully calculated and selected to slow motion at a safe rate.
What should this all look like? Ice was natural, but ideas ranged from transparent to solid. A number of materials were tested; from lightweight fabrics to traditional scrims to projection screens and plastics. The design team finally settled on a sheer Trevira (in short supply and available only from a single factory in Europe). The fabric was cut to form by Big Image Systems on a computer controlled cutting machine and sewn to create large panels that completely covered each section of the horse. These panels would later be attached with double sided tape on site. It was important that the fabric be removable, to allow maintenance of the lighting that would be installed behind it.
The framework in aluminum required no extra finishing. The outer edge was covered first with clear plastic which would provide support for the fabric and the LED edging, and finally with polystyrene mirror, which nicely covered the edges of the fabric and hid the cables. The most difficult part was actually covering the inner edges with glitter – as this had to be done by hand, and the Divinycell core required priming.
To light the horses, all parts were edged with LED, powered from 48V dimmers placed in cabinets on the bicycle frame.
Finding a 20 meter high hall for a full scale test was also a major hurdle. The space was found in an underground shipyard and the tests, only three weeks before delivery, proved that the engineering was correct.
The Troika, along with transport trolleys and other support equipment, was then trucked to Sochi on four trailers, only to be held up by a winter storm that blocked the port for a week. The 16 day installation period became 8 days. This was no problem for Visual act. The installation was made in time with great success.