Light curtain localization via compressive sensing

Light curtains are presence detection devices, typically employed to detect when an object enters (or passes through) a region to initiate emergency security procedures. However, most existing light curtain implementations are not designed to detect the precise location where the barrier was broken. In this paper, we present a hardware prototype implementation that is able to identify the locations where the light curtain was broken, even if multiple objects penetrate the barrier simultaneously. To this end, we deploy techniques from sparse signal recovery and compressive sensing to perform detection and localization with only a few infrared transmitters and sensors. The proposed prototype implementation is scalable to large physical sizes and can be tailored to suit a particular application in terms of the number and size of objects to detect, as well as the desired spatial resolution.