Mountainous road parameters fitting and driving safety analysis based on GPS/IMU

In order to effectively obtain mountainous road alignment parameters and to reduce the accumulated error in measurement, a method to estimate road geometric parameters based on GPS/inertial measurement unit (IMU) was proposed. With the three-dimensional characteristics of the earth surface considered, the state equation of vehicle driving based on GPS expression with Cartesian coordinate system was established, the road was described section by section, and smooth processing was conducted with the combination of the measurement information from IMU. The geometrical parameters of road gradient and turning radius were obtained by recursive estimation and the effects of road gradient, turning radius and velocity on driving safety were analyzed. The results show that the parameters information with the proposed method have a good agreement with that by the mining point, which proves the method to be effective. The driving safety can be improved by enhancing the turning radius and limiting the velocity which have greater effects on driving safety compared with road gradient.