Determination of the walking direction of a pedestrian from acceleration data

In recent times, infrastructure-free indoor positioning has been an important topic of research. Many of the proposed systems are based on pedestrian dead reckoning, thus relying on estimating the heading of the pedestrian. While many studies successfully address the problem of estimating the heading of the device, current approaches have the limitation of requiring the device to be aligned with the pedestrian. To address this problem, we propose an algorithm for estimating the misalignment between the pedestrian and the device by evaluating the acceleration data fit a simplified gait model in each direction. Contrary to similar algorithms, the proposal in this paper does not require a previously trained model nor the detection of steps, and can be implemented using only acceleration data. Furthermore, our experimental results show a significant improvement over the current state of the art.