Nowadays, indoor visible light positioning (VLP) is one of the hottest technologies in the field of positioning; as a result, a number of algorithms for VLP have been proposed. However, unfortunately, few algorithms can be applied to the case that the receiver is tilted. In order to solve this problem, we developed a three-dimensional indoor VLP algorithm which can work effectively and accurately when the lens is tilted. When the lens is far away from the LED, the image of the LED is approximately regarded as an ellipse, and the distance between the two is obtained through the geometric relationship, and we finally achieve the positioning of the camera by the triangulation algorithm. The quantitative results show an average error of 6.74 cm when the tilt angle is estimated to be within 30°. At the same time, we propose an ID allocation scheme, which can effectively reduce the demand for ID.

With the development of robotics, multi-robot collaboration system (MMCS) has become a popular focus of research in recent years. As the key technology of MMCS, multirobot cooperative localization (MRCL) is becoming more and more popular due to its higher accuracy and robustness by exchanging and sharing information. In this paper, we propose a MRCL system based on visible light positioning (VLP) technology and odometer (VO-MRCL). Using rolling shutter camera and odometer, the system relaxes the quantity required of observable light emitting diodes (LED) lamps of each robot to one and improves robustness of VLP-based robot positioning methods under LED shortage. The accuracy of the proposed VO-MRCL system is verified by real-world experiments, where a two-robot system is proposed as an example specifically. The results of experiment show that our proposed system is feasible and can achieve the positioning accuracy with an average error of 4.31cm.