Research On The Key Techniques Of Shape Measurement Sensor Based On Laser Scanning Triangulation

In the wake of the rapid development of modern manufacturing and industrial information technology,advanced intelligent manufacturing has raised stricter requirements in the area of precision measurement,among which high speed and high precision object contour measurement system plays the most important role in target detection and quality control.In order to meet the detection requirements in new industrial manufacturing industry,modern detection technology has put forward a series of strict standard including high-precision,high-speed,intelligence,and digitalization.This paper proposes and designs a non-contact laser scanning shape measurement sensor based on single-point laser triangular displacement measurement and high-speed rotating prism.The paper describes the principle and calibration method,builds the prototype platform,and completes the related experiments.As in results,the laser triangular scanning measurement sensor developed in this paper demonstrates the accuracy better than 0.25 mm,which meets the original designing requirements and proves the feasibility of this design proposal.The main work of this paper is as follows:1.We design a shape measurement sensor based on laser triangular scanning aimed at overcoming the inherent defect of traditional linear structured light triangulation sensor based on existing literature and the state-of-the-art and application prospect of topography measurement technology.This paper studies the basic principle of laser triangulation system,and hence derives the Scheimpflug condition satisfying constant focus.We have analyzed the effect of parameters in system designation on measurement sensitivity,completed the MATLAB simulation about parameter designation of the optical system.2.This paper designs the synchronous scanning system model of the sensor,proposes the designation requirements and parameters,and selects appropriate devices for related components of the senor.We also design proper model of systematic mechanical structure based on related devices,complete the mechanical design and model establishment on Solidworks,and analyze the system's main source of measurement error and the corresponding solutions.3.Through analysis of the commonly used filter methods and spot location algorithms,combined with the image characteristics of the system,we choose to use the mean method to filter image,and propose an improved spot location algorithm.We also study the impact of oblique laser beam on spot location,identify the relevant factors,and propose a symmetric measurement calibration method to verify the influence degree of the tilt error.4.Overall,this paper introduces a non-parametric calibration method applicable to the system developed here,assembles the experimental prototype,establishes the systematic experimental platform,and completes experiments in a number of keys aspects such as stability,repeatability,calibration of error compensation from beam tilt and of the sensor itself,and accuracy verification of sensor system with the help of laser tracker.