Design And Research Of Retroreflective Coefficient Detector Based On Embedded System

Retroreflection is a reflection of the reflected light returning from the direction opposite to the incident light.The retroreflective material is a new type of material developed based on the principle of retroreflection,which can improve the visibility of long distance,especially the night visibility.It is precisely because of this unique visual characteristic,retroreflective materials are widely used in road traffic safety products.The retroreflective coefficient is the key index to evaluate the performance of the retroreflective material.This paper studies and analyzes the retroreflective coefficient measurement method and the embedded system technology.Taking S3C2416 as the core processor,using the retroreflective coefficient relative measurement method to design a small volume,high precision portable retroreflective coefficient detector,real-time accurate the retroreflective coefficient.The overall design of retroreflective coefficient detector is put forward based on the principle of the relative measurement method through the study of the retroreflective coefficient measurement method.Measuring optical path is designed by the use of optical element plane mirror and the semi-reflective semi-transmissive mirror to meet the characteristics of short distance and high precision of retroreflective coefficient detector.Kohler illumination system is designed to improve the illumination uniformity of LED.The circuit design is completed by using S3C2416 processor as the core of hardware circuit which includes hardware function module involving power,memory,LCD touch screen,network and communication inter1 face and illumination measurement module involving illumination sensor BPW21,signal conditioning circuit and A/D conversion through the study of the characteristics of processor S3C2416.The application program adopts the embedded Linux operating system and Qt graphics application development framework,and establishes the host application development environment and the target software operating environment through the cross compilation way,and completes the human-computer interaction interface development and system test and data analysis.The data fitting method of least squares method is used to fit the data of each color standard sample and obtain the calibration function of the specific color.The test sample test is completed by the use of calibration function.In order to ensure the accuracy of the instrument,the test data were tested for repeatability and compared with the standard sample retroreflective coefficient test.The results show that the retroreflective coefficient detector designed in this paper can meet the testing requirements.