A grid of 8*8 modules, each of them constituted of 8*8 motorised squared tiles constitutes a horizontal surface. The size of the subdivision of these modules is insprired by Mies van der Rohe's Dominion Center's ceiling's subdivision and confronts the artificial light architecture with a kinetic 'natural light' one. This horizontal surface becomes a 'ceiling', an 'artificial sky', just like a pergola - hence the working title.

Each of the tiles has a light reflective (whitish, polished inox) side and a light absorbing (black) side and can spin around its horizontal axis. The bi-chromatic treatment of the tiles produces a contrast in between its sides, playing on two light characteristics, reflection and absorption. A light play constituted of reflection and shadow is created out of the tiles' movement.