From Stars to Drops of Water

In the Olympic Park at the Winter Games in Pyeongchang: Between sports stadiums and sponsors, a black hole stands out. Only when you get closer can the eye discern individual contours. Illuminated by thousands of flickering LEDs, the “darkest building in the world” develops an inherent pull that seems to violate all physical laws.

The bewildering effect is created because the concave facade of the Hyundai Pavilion is finished with Vantablack VBx2, a coating that absorbs over 99 per cent of the incident light. Against this backdrop, thousands of LEDs were installed; their arrangement and individual intensity are modelled on the starry sky above Pyeongchang.

Moving inside the building, the contrast could not be greater. You find yourself in a brightly lit room, completely white, with a large water installation in the middle.

Tiny droplets of water run through grooves cut into the surface and collect in the middle of the installation. Controlled by various sensors triggered by the visitors, the individual drops form a fascinatingly sparkling whole before disappearing after a few minutes through a drain and the fun starts all over again.

By jumping from the infinite expanse of the star-studded sky to the scale of a single drop of water, the South Korean car manufacturer Hyundai wanted to draw attention to its hydrogen-fuelled vehicles without presenting a specific product. iart helped turn this ambitious desire into reality.

In order to be able to control each LED of the four façade segments individually, the iart team localised them with the aid of a high-resolution camera and developed software for their operation. In order to implement the water installation, experiments were carried out with the Institute for Thermo- and Fluid-Engineering at the FHNW. There, the behaviour of different sized water droplets on the hydrophobic surface was investigated and the processes of keeping the water clean were defined.