Regent AG, a large Swiss company offering lighting solutions, asked us to realize a futuristic light concept for their stand at the Light & Building fair 2016 in Frankfurt, Germany. They asked for a ceiling light which could follow or lead a person through the building. We devised a solution of wheeled robots which hang upside down on the ceiling by using strong neodyme magnets. Balancing the strength of the magnets and therby having not too much and not to less friction for driving was a first mechanical challenge.
Within just four months we realised an actual working prototype. Besides developing a customised multilayerd software system, we also innovated many novel techniques. These include a positioning system for the robots, a tracking system for people entering the room, a collision avoidance system between the robots and the embodiment of the robot itself. The robots communicate wirelessly to each other to exchange their own position and get the poeple’s position from a central tracking computer system. As a result the robots can move freely, safely and well orchestrated around the ceiling.
The robot positioning system is implemented in C/C++ and involved visual fiducial marker recognition. The capturing camera uses infrared light to minimize environmental light disturbance. Some elaborate optimizations improved the positioning accuracy to about 2 millimeters, depending on the infrared camera resolution used. Furthermore, the system works very robustly, even if the pattern is defective in some places.
The central ground control system is implemented in .NET/C# and offers a graphical user interface to observe and control all active robots on a virtual map. This central component also handles automatic real-time collision avoidance, evaluation of the tracked people’s positions and future path calculations of the robots.
