An active 3D robot camera for home environment

Service robots, such as robots working in a home environment, need very robust and reliable sensing mechanisms. In this paper, we present a 3D camera based on structured light suitable for robots working in the home environment. First, we show that the degradation of precision and robustness comes mainly from the overlapping of multiple codes in the signal received at a camera pixel. Then, we propose a novel signal separation coding providing not only the separation of overlapped codes, but also a robust decision on pixel correspondence with error correction. The proposed method was implemented using an invisible IR (infrared) pattern of lights in order to avoid user inconvenience in the home environment. The experimental results showed that the proposed algorithm significantly enhances the robustness and precision in depth imaging, compared to the best known conventional approaches. The proposed approach opens a greater feasibility of applying structured light based depth imaging to the 3D modeling of a cluttered workspace for home service robots.