Research And Design Of Vehicle Length And Height Detecting System With A Laser Sensor Based On Related Algorithms

With the rapid development of China’s road transport industry, vehicle overrun and overloading phenomenon is becoming increasingly serious. The overrun transportation of large goods vehicles and cars with hanging damaged the roads and bridges, and harmed the traffic safety and the order of transport market.In order to meet the transport sector’s demand of the overrun control and achieve automated and intelligent control of large trucks overrun, this paper research and design the vehicle length and height detecting system with a single laser sensor based on the related algorithm and curve fitting.Through market research and field survey on the highway overrun detection station, this paper identified the system solutions which using a single laser sensor of LMS-111 to dynamic measuring of vehicle max-length and max-height.This paper deeply studied the measurement algorithm of vehicle length and height.The measurement algorithm using related algorithm to calculate the vehicle length value based on the detecting and calculating the height value. In order to verify the correctness of the methods mentioned above, firstly did programming simulation experiment in MATLAB environment, and then physical test in the actual field.The results show that above method is indeed feasible and effective.Found in the course of study, the laser sensor may not occur echos phenomenon while scanning object, which results in local singular value (hereinafter referred to as bad value) in the sequence of data collected by the computer, and affects the accuracy of detecting the vehicle length and height. In order to solve this problem, the polynomial least squares curve fitting algorithm is introduced, which using the ideal values in the height data acquisition sequence to do a polynomial curve fitting to get the vehicle height utilizing the fitted values to replace the bad value, and then to do related operations to obtain the length of the vehicle finally.The experiment proved that polynomial least squares curve fitting can improve the measurement accuracy.Finally, this paper rapidly designed and developed a upper computer software by using mixed programming mode with Visual Basic and Mideva and SQL Sever 2000 database,which can show the test result by sound and light,store data,inquiry historical data and so on. This software has some advantages, such as friendly interface, complete function, simple operation. In the testing phase, the system was running fast, measuring in high accuracy, working continuously with good stability,which can basically meet the demand of the relevant departments to detect automatically the vehicle length and height,and has a some practical value.