TRAVELING DIRECTION DETERMINATION DEVICE, MOBILE DEVICE, AND TRAVELING DIRECTION DETERMINATION METHOD

Provided is a traveling direction determination device that determines, using an acceleration sensor that generates acceleration signals indicating acceleration in three axial directions together with a direction of the acceleration, a traveling direction of a moving object mounted with the acceleration sensor, the traveling direction determination device comprising a determination unit that executes a first determination process in which the determination unit selects, using the acceleration signals, any of the three axes as a gravity axis, the gravity axis being closest to an actual gravity direction of the moving object to determine a gravity direction of the moving object and a second determination process in which the determination unit selects either of the two axes excluding the axis selected as the gravity axis, as a travel axis, the travel axis being closest to an actual traveling direction of the moving object based on moving average values of the acceleration signals to determine the traveling direction of the moving object.