Study On Lane Departure Warning Technology

With the increase of car ownership and traffic accident remains high, the car safety became an important part of traffic safety. So traffic safety problem became prominent. Especially at night without lights road, limited by car headlights irradiation distance, driving at night there is a big security hidden danger. Night traffic accident causing death toll to more than 75%, of which the main cause of traffic accidents is that driver fatigue causing the vehicle deviates from the driving lane at night. In order to solve the engineering problem,this topic uses laser night vision instrument to get road image information then Analysis the driving conditions of vehicle.First,establishing lane model to obtain the relationship between the lane departure rate and the slope of the lane line in the image. Secondly,the use of camera calibration to determine the installation parameters of laser night vision instrument. Finally,preprocess the collected image and calculate lane departure rate by through image extraction algorithm. Then will obtain lane departure rate and display through the lane departure warning interface.The main research contents are as follows:(1) Establish the lane departure model by using the coordinate conversion between the theory of machine vision system. In the model, induce the calculation formula of deviation rat concisely through intrinsic and extrinsic parameters of camera settings. The camera internal parameters is determined by camera fixed focus experiment to determine. External camera parameters was obtained by the camera installation parameter testing experiments. Determine the affect on lane departure rate of height and direction angle based on the analysis of the effects on the test.(2) According to the lane model establishment condition and the camera calibration results, the laser night vision device is installed in the vehicle. Preprocessing and feature extraction of intra regional lane by the captured image, and calculate the lane image parameters by Hough into the lane model to calculate the lane departure rate.The results of theoretical calculation are compared with experiment lane departure threshold to judge whether deviate,and ultimately to display in the warning interface.