Using a three-axis accelerometer and GPS module in a smart phone to measure walking steps and distance

In this paper we use a smart phone with three-axis accelerometer features together with a multiple judgment method to improve the accuracy of measuring both walking and running steps. In the past, using only a single characteristic for ascertaining whether there is a walking step resulted in large errors while on the other hand the multiple characteristics of acceleration variation are used to decide the presence of walking steps, thus effectively enhancing accuracy. By using a GPS module this design estimates both the user walking distance and the user path as depicted on the GPS map, and then allows the user to estimate the amount of exercise.