Development of a pedestrian navigation system using shoe-mounted sensors

Global navigation satellite systems are commonly used for personal positioning, providing high accuracy as long as a clear signal is available. In thick forest, urban areas with tall buildings, and indoor environments satellite positioning accuracy is degraded, and sensor based systems are a practical alternative. The purpose of this research is to explore and understand methods of applying shoe mounted sensors for pedestrian navigation. Using miniature, inexpensive sensors it is possible to create self-contained systems using sensor-only navigation techniques optimised for pedestrian motion. The systems developed extend existing foot based stride measurement technology by adding the capability to sense direction, making it possible to determine the path and displacement of the user. The proposed dead-reckoning navigation system applies an array of accelerometers and magneto-resistive sensors worn on the subject's shoe. Measurement of the foot's acceleration allows the precise identification of separate stride segments, thus providing improved stride length estimation. The system relies on identifying the stance phase to resolve the sensor attitude and determine the step heading. Proof of concept tests were performed in the laboratory using video motion capture equipment, and field trials were carried out in forested conditions. Performance metrics include accuracy of step detection, foot angle, foot velocity, stride length estimation and heading with respect to a high accuracy reference trajectory.