Abstract
This thesis investigates two techniques for tracking the trajectory of a pedestrian using one and two foot-mounted inertial measurement units (IMU) called EcoIMU. Each EcoIMU transmits data from its 9 degree-of-freedom (9-DoF) inertial sensor, i.e., accelerometer, a triaxial gyroscope, and a triaxial compass, via Bluetooth Low Energy (BLE) protocol to a PC for analysis. We propose an algorithm to calculate the orientation and trajectory in 3D by two-degree Savitzky-Golay filter (TDSG) with zero-velocity update, and we use Madgwick algorithm and heading direction method to reduce the error. First experimental results show that accuracy of orientation and distance error from double integration can be improved by TDSG and Madgiwck methods successfully. Second experimental results show that by adding ultrasonic sensor to limit the distance between two IMU on different feet, the drifts on stride widths can be reduced significantly. Our proposed techniques also achieve less error disance compared to the state-of-the-art in indoor localization.