We designed and implemented two versions of an interactive light curtain as part of the project UHCI (Universal Home Control Interface). The first version is installed in the Serviceplan WeShop in Munich, a showroom for a smart shopping environment. The second version is part of the smart home showroom at DAI in Berlin.
The first curtain, which was designed specifically for the context of a changing room, has a sensor to recognize if the curtain is drawn open or closed. It carries embroidered LEDs on the outside that light up and start to pulsate when the curtain is drawn closed. This signalizes to other customers in a subtle and pleasant way that the changing room is occupied.
The second curtain also has a sensor to recognize its state, but in addition also has an embroidered slider on the front. The slider consists of three large patterns made from copper thread that serve as capacitive antennas. In the DAI showroom, the slider can be used to control either the lighting pattern of the curtain itself, or to control the lowering of the blinds.
Both curtains have the LEDs sewn onto five embroidered copper traces that vertically run along the front of the curtain. The two contact poles of the conductive lines are on the front and back to avoid shortcuts when the curtain is moved. The five sections can be controlled individually, each group being controlled by a different pin on the micro controller which is placed on the upper part of the curtain, together with the small battery or a power connector.
Controlling the curtain in the DAI showroom with the capacitive slider.
Sewing on the micro controller.
Closeup of the embroidered capacitive antenna.