Design And Research Of Laser Triangulation Ranging System

As a kind of contactless ranging method,laser triangulation ranging method has a higher and higher utilization rate.It has many advantages,such as high precision,good real-time ranging and convenient operation.After studying the principle of laser triangulation,a kind of laser triangulation ranging system which can be compensated according to the temperature is designed.Firstly,the laser ranging theory is analyzed,and the triangulation ranging theory is taken as the key research object.The two kinds of ranging methods in laser triangulation,the direct type and the oblique type,are compared.The direct laser triangulation method is simple in structure and has no high requirements on the surface of the tested object.Finally,the direct-type laser triangulation method is selected as the optical ranging principle of the whole system,and the optical path of the ranging system is designed by selecting relevant parameters.Then design hardware circuit system and software system.The whole hardware circuit system is mainly composed of DSP module,laser module and image acquisition module,communication module and a temperature measurement module,the main chip models to choose from several modules,combined with the specific to the DSP chip module,laser module and image acquisition module,communication module and a temperature measurement module circuit design.In software system design.DSP BOOT will be used to BOOT the program to run in FLASH;By comparing the image receiving effects of different laser pulse signal duty ratio,the best duty ratio was determined.Design data receiving program and temperature measuring program according to the timing sequence of CMOS chip and temperature measuring chip;Design analog-to-digital conversion program and data transmission program,and finally design the interactive interface of upper computer.Build test platform and debug software to make each module operate normally as expected.CMOS output signals can be collected,stored,transmitted and displayed.According to the noise characteristics of the data collected by the linear array CMOSdata acquisition module,several filtering smoothing algorithms are compared,and finally the low-pass filtering and mean filtering methods are adopted to filter the collected data.Several methods to get the center of mass are compared.Finally,the thinning algorithm of weighted square center of mass is used to get the center of mass.The repeatability experiment is carried out on the system.Due to the different characteristics of the measured surface and the environment,to influence ranging system being measured on the surface of the analyte to choose the color,roughness,slope Angle,and tested in the environment temperature has carried on the experiment,and analyze the data,based on high precision machines and sliding table,it is concluded that different error of the measured value and the influence factors of the measured surface and the environment of error analysis and data compensation experiment was carried out.Finally,the error factors and improvement methods of the whole system are put forward.