摘要
隧道净空全断面视觉检测系统空间测量尺度大、视觉传感器分布广、不同视觉传感器无公共视角。采用合适方法对其进行高精度全局标定,是实现隧道净空全断面高精度测量的关键。本文将二维平面靶标与一维靶标相结合,对视觉测量系统进行全局标定:采用二维平面靶标对单个摄像机内部参数进行离线标定;借助一维靶标上距离已知的共线特征点作为约束条件,求解相邻摄像机外部参数,通过相邻摄像机外部参数两两换算,逐个求取单个摄像机坐标系与全局坐标系外部参数,同理求得激光平面方程系数。综合所有摄像机内外部参数、激光平面方程系数,建立隧道净空全断面视觉测量模型。对研制的隧道净空全断面动态测量系统进行标定和动态测量试验,结果表明该标定方法切实可行。
The tunnel clearance full cross-section visual measurement system features wide space measurement range and wide distribution of vision sensors which provide no shared angle of view..The use of appropriate method to achieve the high precision global calibration of the system is crucial to realize high precision measurement of full cross-section of tunnel clearance.This paper integrated the 2Dplanar target with 1Dtarget to perform global calibration for the visual measurement system：The intrinsic parameters of each camera were calibrated off-line,subject to the 2Dplanar target.Based on the collinear feature points with known distances on one-dimensional target as a constraint condition,the extrinsic parameters of neighboring cameras were obtained.Through the conversion of extrinsic parameters of neighboring cameras,the coordinate frame of a single camera in relation to the global coordinate frame was computed one by one.Similarly,the coefficients of the laser plane equation in the global coordinate frame were determined.By the combination of all the intrinsic parameters,the extrinsic parameters and the coefficients of the laser plane equation in the global coordinate frame,the global measurement model was set up.The calibration and dynamic experiments for the tunnel clearance full cross-section visual measurement system were carried out.The experimental results demonstrated the effectiveness of the proposed calibration approach.
出处
《铁道学报》
EI
CAS
CSCD
北大核心
2015年第7期98-106,共9页
Journal of the China Railway Society
基金
国家自然科学基金(51177137
61134001
U1234203)
国家高技术研究发展计划(863计划)(2011AA11A102)
中国铁路总公司科技研究开发计划(2014G008-C)
关键词
轨道交通
隧道
三维净空
动态测量
标定
railways
tunnel
3Dclearance
dynamical measurement
calibration
