T型光电经纬仪的投影中心和三差检测方法研究  

Projection Center and Triple Difference Detection Method of T-Type Photoelectric Theodolite

作　　者：刘耀登 吕耀文 杜博军 宫玄睿 黄玺 Liu Yaodeng;LüYaowen;Du Bojun;Gong Xuanrui;Huang Xi(Key Laboratory of Optoelectronic Measurement and Control and Optical Information Transmission Technology,Ministry of Education,School of Electro-Optical Engineering,Changchun University of Science and Technology,Changchun 130013,Jilin,China;Unit 63850 of the People's Liberation Army,Baicheng 137001,Jilin,China)

机构地区：[1]长春理工大学光电工程学院光电测控与光信息传输技术教育部重点实验室,吉林长春130013 [2]中国人民解放军63850部队,吉林白城137001

出　　处：《光学学报》2024年第2期180-189,共10页Acta Optica Sinica

基　　金：吉林省自然科学基金(YDZJ202201ZYTS419);高等学校学科创新引智111计划(D21009)。

摘　　要：在靶场测量中,针对负载式T型光电经纬仪在更换成像组件之后的投影中心和光轴平行性改变的问题,提出一种仅需2个标杆即可同时检测投影中心和光轴平行性三差的方法。首先,结合摄像机的小孔成像模型和光电经纬仪的三差,推导了大地测量坐标系下的一点与摄像机图像平面上像点之间的投影方程。其次,根据光电经纬仪正、倒镜拍摄两根标杆得到标杆顶点在图像平面上的投影坐标,推导了结合投影中心与三差的成像投影关系,分析了平移矢量和三差对于标杆顶点在成像平面上投影点脱靶量的影响,对系统的投影中心坐标和三差进行计算,进而实现对光电经纬仪的光轴平行性检测。最后,通过实验验证了所提方法,实验结果表明,引入中心投影坐标和三差之后,水平方向和垂直方向上的重投影误差分别在0.2744 pixel和0.2287 pixel以内,所提方法切实可行、精度较高,可应用于T型光电经纬仪在靶场光轴平行性检测过程。Objective T-type theodolite is widely used in various test tasks due to its large measurement range,non-contact feature,high measurement accuracy,replaceable load sensor,and availability for multi-sensor sharing.The T-type theodolite has a load-carrying structure.For different test environments,different load imaging components can be installed on its side axis to reach the measurement purpose.However,after replacing the imaging detection sensor,the projection center of the optical imaging system and the position relationship between the imaging optical axis and the alignment axis of the T-type photoelectric theodolite will be changed.These factors will lead to angle deviation of the T-type photoelectric theodolite in the measurement.Therefore,the triple difference and the projection center coordinates of the T-type theodolite need to be calculated and eliminated.For the study of photoelectric theodolite,there is a lack of effective methods to simultaneously detect the projection center and triple difference.Therefore,a simple method of measuring the triple difference of T-type photoelectric theodolites is proposed in this paper.The photoelectric theodolite imaging system collects images of the near and far station poles respectively.Then,the projection center coordinates of the imaging optical system can be calculated from the image coordinates of the poles,the intrinsic parameters of the imaging system,and the encoder value of the photoelectric theodolite,thereby achieving the detection of optical axis parallelism.Methods Firstly,the projection equation between a point in the geodetic coordinate system and the image point on the camera image plane is derived by combining the transformation relationship of the related coordinate system[Fig.1(a)]and the camera's pinhole imaging model[Fig.1(b)],as well as the triple difference of the photoelectric theodolite.Secondly,the projection coordinates of the station pole vertex on the image plane are obtained according to the positive and reversed images of the photoelect

关 键 词：测量 光电经纬仪 光轴平行性 投影中心坐标 三差 

分 类 号：TH761[机械工程—仪器科学与技术]