1992

Hakala, Hannu

Several types of navigation systems have been considered for automotive navigation. These systems must have at the same time suffici ently good performance, reasonable price, simplicity, and convenient operation. Almost all the vehicular navigation systems have one common feature: basic in-car navigation is based in these systems on dead reckoning, which is enhanced with other methods like map matching, proximity beacons, or satellite navigation systems. This paper describes the method of dead reckoning in vehicle navigation applications. Terminology used in this area is explained. Th e basic theory of dead reckoning is given. The principles of common types of odometers and differential odometer are described as we ll as the physical phenomena, structures, and examples of odometer realizations made with different techniques. Other distance measu rement devices are also described. The other component of dead reckoning calculations, heading, can be measured with magnetic compas ses, gyroscopes, optical gyros, and other means. These methods are explained and component realizations are shown. Inertial navigati on systems are described shortly in order to give the reader some basic information for comparison between dead reckoning and inertial navigation methods. The last two chapters include some examples of vehicular navigation systems that are utilizing the method of dead reckoning alone an d with map matching.