路基表面沉降视觉检测系统光斑中心定位方法研究

激光光斑中心精确定位是铁路路基表面沉降视觉测量系统的关键技术,关系沉降测量的精度.分析了铁路路基表面沉降视觉测量的基本原理,结合激光光斑图像的特点,在以光斑轮廓邻域的灰度分布进行曲面建模的基础上提出基于曲面拟合的光斑亚像素中心定位方法,并通过实验验证了该方法光斑中心定位精度优于常用的基于重心灰度分布曲线拟合法,定位精度高且鲁棒性好,达到了铁路路基沉降观测精度的要求.

Method of Laser Spot Center Positioning of Visual Inspection System for Subgrade Surface Settlement

The precise location of the laser spot center of railway subgrade surface settlement is critical to settlement measurement accuracy and the key technology of the vision measurement system.With the basic principle of the visual measurement of railway subgrade surface settle-ment,the surface model of spot image neighborhood gray distribution has been established com-bined with the characteristics of the laser spot image gray distribution.The sub-pixel center posi-tion of the laser spot image method based on curved surface fitting is put forward.Laboratory tests show that the proposed method is better than that commonly used gravity gray distribution curve fitting which has high positioning accuracy and good robustness,and appropriated to the monitor accuracy requirements of railway subgrade settlement monitoring system.