Inclinometer Assembly Error Calibration and Horizontal Image Correction in Photoelectric Measurement Systems
Xiaofang Kong,
Qian Chen,
Jiajie Wang,
Guohua Gu,
Pengcheng Wang,
Weixian Qian,
Kan Ren,
Xiaotao Miao
Affiliations
Xiaofang Kong
Jiangsu Key Laboratory of Spectral Imaging and Intelligent Sense, School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
Qian Chen
Jiangsu Key Laboratory of Spectral Imaging and Intelligent Sense, School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
Jiajie Wang
Jiangsu Key Laboratory of Spectral Imaging and Intelligent Sense, School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
Guohua Gu
Jiangsu Key Laboratory of Spectral Imaging and Intelligent Sense, School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
Pengcheng Wang
Jiangsu Key Laboratory of Spectral Imaging and Intelligent Sense, School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
Weixian Qian
Jiangsu Key Laboratory of Spectral Imaging and Intelligent Sense, School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
Kan Ren
Jiangsu Key Laboratory of Spectral Imaging and Intelligent Sense, School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
Xiaotao Miao
Jilin Jiangji Special Industries Co., Ltd., Zun Yi West Road 17#, Jilin 132021, China
Inclinometer assembly error is one of the key factors affecting the measurement accuracy of photoelectric measurement systems. In order to solve the problem of the lack of complete attitude information in the measurement system, this paper proposes a new inclinometer assembly error calibration and horizontal image correction method utilizing plumb lines in the scenario. Based on the principle that the plumb line in the scenario should be a vertical line on the image plane when the camera is placed horizontally in the photoelectric system, the direction cosine matrix between the geodetic coordinate system and the inclinometer coordinate system is calculated firstly by three-dimensional coordinate transformation. Then, the homography matrix required for horizontal image correction is obtained, along with the constraint equation satisfying the inclinometer-camera system requirements. Finally, the assembly error of the inclinometer is calibrated by the optimization function. Experimental results show that the inclinometer assembly error can be calibrated only by using the inclination angle information in conjunction with plumb lines in the scenario. Perturbation simulation and practical experiments using MATLAB indicate the feasibility of the proposed method. The inclined image can be horizontally corrected by the homography matrix obtained during the calculation of the inclinometer assembly error, as well.
