Full Scale Experiment with Interactive Urban Lighting

This paper presents and discusses the results of a full-scale interactive urban illumination experiment. The experiment investigates how human motion intensities can be used as input for controlling the illumination of a town square in the city of Aalborg in Denmark. The trajectory, velocity and region of occupancy of persons in the town square were monitored in real time by computer vision analyses of thermal images from 3 cameras monitoring the square. The results of the computer vision analyses were used to control the illumination from 16 3.5 meter high DMX controlled RGB LED Lamps that were distributed across the square in an irregular grid. Using architectural models as sketching tools, 4 different responsive light scenarios were designed and tested for a week in January. The result shows that in general people on the square did not notice that the light changed according to their presence or actions, whereas people watching from the edge of the square noticed the interactions between illumination and the persons. The current experiment also demonstrated that interactive lighting can make significant power savings. In the current experiment there was a difference of 92% between the most and the less energy consuming light scenario.