Indoor Localization, Tracking, and Mapping With Heterogeneous Technologies

The articles in this special section focus on the use of heterogeneous technologies for indoor Localization, tracking, and mapping. Accurate availability of position opens the way to enhanced system performance and functionalities, such as automated guided vehicles and people movers. While satellite-based positioning systems (generally referred to as Global Navigation Satellite Systems, namely GNSS, including GPS, GLONASS, and Galileo) provide position information that is accurate enough for most applications in outdoor environments, they usually do not work well in close or harsh environments. Therefore, other localization technologies must be considered. In some scenarios, such as inside buildings and unexplored caves, even the map of the environment might not be available. Thus, the localization processes have to be executed in parallel to mapping [i.e., simultaneous localization and mapping (SLAM)], making the problem even more challenging. Different from outdoor applications and the reliance on GNSS, for indoor applications, there is no single dominant technology that can meet a sufficiently wide range of requirements. As a result, a plethora of solutions has been investigated over the past decade. A current trend in indoor localization and tracking is to use a combination of standards, low cost, and already-deployed technologies and resort to statistical fusion of the information they provide.