Indoor Mapping And Accuracy Evaluation For Pedestrian Localization

People generally spend around 90% of their time in indoor space every day, and they also hope to have a high-precision real-time location based system for indoor real-time location services, e.g. indoor pedestrians localization and navigation. Indoor mapping and accuracy evaluation are important components for pedestrian localization, because indoor digital maps are the basis and information carrier of indoor real-time positioning, and we must have a detailed indoor digital map for confirmation, and auxiliary display positioning results no matter what location technology is employed. Accuracy evaluation is very momentous, as it would be useless and unacceptable with an indistinct accuracy to numerous applications and services. Researches on indoor mapping for indoor pedestrian positioning are focused on the use of maps and map visualization, rather than on localization assisting. For the accuracy measurement, Cross-track-based method has a low accuracy, and the Marker-based and Video-based method is labor intensive, people intervention and non-environmental. What’s more, there is no research on evaluation for the methods itselves.The main contributions of this thesis can be summarized as follows:(1) We take the indoor pedestrian positioning as the breakthrough point, and make a deeply research on indoor features, including indoor constrains, variability, privacy, special entities etc. The requirements of size, dimension, geometric elements, symbolic coordinates, mapping accuracy and indoor entities for pedestrian localization are put forward. We also give a light data structure of indoor map and explore mapping methods of 2D floor plan and 2.5D maps for indoor pedestrian localization.(2) We summarize a framework for the accuracy assessment of pedestrian positioning. Advantages and disadvantages of three indoor pedestrian positioning accuracy assessment methods, including Cross-track-based, Marker-based, and Video-based are analyzes in detail. What’s more, we present a new method based on landmark, which is using sensors smart phones to sense the environment to realize the accuracy measurement without intervention, thus overcoming the heavy workload, time-consuming and non-environmental shortcomings.(3) We conduct a series of experiments in an office building named Engineering Laboratory Building in China University of Geosciences to evaluate the proposed mapping method and accuracy ecaluation method. A multi-floor planned path is planned through the third and fourth floor. The result shows that the accuracy of three methods in order is Marker-based (0.5m)≥Landmark-based(0.8m)≥Cross-track-based (1.5m), namely, the proposed method have a better effectiveness and performance in overall.