A personal navigation system using MEMS-based high-density ground reaction sensor array and inertial measurement unit

This paper describes a prototype personal navigation system developed for position tracking under GPS denied environments by employing a commercial inertial measurement unit (IMU) and a MEMS-based ground reaction sensor array (GRSA). The GRSA is used to provide zero-velocity updating for the IMU. A Kalman filter further estimates the IMU output bias during the zero-velocity period, which is then removed from the IMU's subsequent output signals to improve the navigation accuracy. Seven 10-minute square-loop walking tests were performed to achieve an in-plane navigation accuracy ranging from 0.4 meter to 3.4 meter with a vertical position accuracy of approximately 1 meter. A further improved performance over an extended navigation time is expected through enhancing the GRSA sensitivity.