A Gyroscopic Data based Pedometer Algorithm with Adaptive Orientation

Orientation of an Inertial Measurement Unit (IMU) relative to earth is a critical factor to the step detection in gyroscopic data based pedometer algorithm. The orientation of the IMU will be often subjected to change while using the small scale electronic pedometers. Existing fixed axis gyroscopic data based pedometer algorithm may not be suitable to implement in the modern small scale embedded pedometer applications. In this paper we have developed an advanced version of the gyroscopic data based pedometer algorithm which can dynamically adjust for the changing orientation of the IMU. Step detection component of the proposed algorithm is based on the gyro readings and the orientation detection is based on accelerometer readings. The algorithm employs the gravity vector and linear acceleration vector of the pedestrian to identify the orientation of the IMU. The active gyroscopic data axis for the pedometer algorithm is chosen based on the orientation.