Indoor positioning systems in GPS-denied environments are rapidly becoming popular. Various options are commonly available (BLE, Wi-Fi, ultra-wideband, ultrasonic, etc.). The key challenge is to provide accurate, and stable real-time user location at a low cost. In this paper, we present the research and production details of the developed hybrid indoor localization and navigation system (HILN). The proposed technical solutions are based on cheap Bluetooth beacons and mobile sensors. In particular, we describe two separate positioning pipelines for open spaces and narrow  environments. The scheme of efficient fusion of inertial navigation system (INS) and BLE navigation system is proposed. All the developed solutions are integrated into the mobile indoor software development kit (SDK). Its main components are briefly mentioned. Our mobile positioning system provides 1-2m accuracy and works on Android and iOS devices in a real-time basis.

Mobile Indoor Navigation: From Research to Production