Pedestrian dead reckoning using a novel sensor module that interfaces with modern smart devices

Tracking individuals in areas such as dense urban environments and building interiors is desirable for numerous critical applications, but has been problematic mainly because of the unreliability or unavailability of GPS in many locations of interest. To date, tracking applications that utilize inertial sensors within smart devices have had varied degrees of success: accuracy typically dips below that of standard GPS within minutes and depends strongly on the quality of the sensors in the device, as well as the location that the device is carried on the body. In this paper we present a sensor module that interfaces with modern smart devices and which utilizes a low-cost, commercial-off-the-shelf, 9-axis IMU and pressure sensor to provide an advanced pedestrian dead reckoning solution. The sensor module is designed to communicate with the smart device (e.g., iOS, Android or Windows) via the audio jack and is intended for use as a beltmounted pedestrian tracker. In addition to describing the device hardware and functionality, we present our approach to processing the sensor module data streams to determine a user’s position. Results using the prototype sensor module in operationally relevant scenarios is presented and discussed.