Research On The Vehicle Driving Road Segment Determining Method In Three-dimensional Traffic Environment

Intelligentization is one of the important directions for the development of the current automotive industry.Accurate road segment positioning technology is a prerequisite for smart car macro planning and navigation.At present,in-vehicle commercial positioning systems cannot effectively identify road conditions on and under bridges in complex three-dimensional traffic environments such as viaducts and multiple forks,and cannot be directly applied to smart cars.Most of the smart cars at the research and development stage use high-precision combined positioning technology to determine the car location,but they are expensive and cannot be industrialized.In the three-dimensional traffic environment,high-precision,low-cost vehicle positioning technology has become a current research hotspot and difficulty.The analysis found that the in-vehicle commercial positioning system cannot be applied to three-dimensional traffic environments such as uphill and downhill,elevated interchanges,etc.because of lack of elevation information and low measurement accuracy.This paper explores the principle of high-precision combined positioning,using the on-board CAN bus instead of the IMU to obtain the vehicle movement status,combined with low-cost GPS to determine the historical trajectory of the car over a period of time,and combined with map information to determine the driving section,the main research contents are as follows:Analyze the principle of the existing high-precision combined positioning technology measurement methods,clarify the technical principle and the required vehicle motion state variables;obtain the vehicle motion state measured by the existing vehicle sensors through the CAN bus,realize the vehicle pitch angle estimation,and obtain vehicle elevation information Extend the two-dimensional track estimation to the three-dimensional track estimation technology,combined with low-cost GPS,perform combined positioning to determine the driving position of the car.Secondly,based on the spatial trajectory of the vehicle over a period of time,it is matched with the road segment information in the map.Using the weight-based road segment matching algorithm,the direction information and distance information in the positioning are comprehensively used to determine the driving road segment of the vehicle.Finally,the method for determining the driving section of the vehicle is experimentally verified.Through the actual vehicle test,the positioning method of the intelligent vehicle driving section proposed in this paper can obtain ideal experimental results,and the driving section of the vehicle can be obtained in some more complicated three-dimensional traffic environments.Positioning.