Abstract
This paper describes how to realize a highly accurate positioning system by the hybrid vehicle navigation without using the map information. Here, we present a strategy based on the hybrid vehicle navigation by an optical rate gyro, a vehicle speedometer and a differential GPS (Grobal Positioning System). Especially, we present a positioning system that extrapolates the trajectory continuously when the radio waves from the satellites are not available for a long time interval. The Kalman filter is employed to estimate the accurate position from multiple-measurements. How to build the state variable equation in order to combine the informations from the vehicle sensors and the differential GPS and how to obtain the covariance of measurement and system noises are described.
The validity of the method was examined by experiments carried out by a real automobile on real circumstances. The highly accurate positioning was obtained without the map information.
