Effect of camera characteristics on the accuracy of a visual gyroscope for indoor pedestrian navigation

Accurate navigation in GNSS degraded environments, namely indoors and in urban canyons, is still an unsolved problem. Other radio positioning systems used for indoor navigation purposes, like WLAN, are dependent on an infrastructure. Alternatively, if the initial position of the user is known, it may be propagated using self-contained sensors, such as digital compasses, rate gyroscopes and accelerometers. However, rate gyroscopes used for measuring angular velocity suffer from drift errors, and need augmentation to provide accurate positioning. Visual aiding is a substantial method for augmenting angular velocity measurements because it suffers from errors of a different nature than those of rate gyroscopes. The concept of a “visual gyroscope” described in this paper is based on tracking the motion of vanishing points in consecutive images and translating the motion information into the rotation of the camera. The motion of the camera may be further transformed into the heading change of the user. This paper assesses different cameras and setup characteristics defining the accuracy and functioning of a visual gyroscope using three different cameras and two setups.