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Journal articles on the topic 'Geometrical calibration'

Author: Grafiati

Published: 4 June 2021

Last updated: 8 February 2022

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1

Draréni, Jamil, Sébastien Roy, and Peter Sturm. "Methods for geometrical video projector calibration." Machine Vision and Applications 23, no. 1 (March 12, 2011): 79–89. http://dx.doi.org/10.1007/s00138-011-0322-3.

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Liu Kai, 刘凯, 龙云飞 Long Yunfei, 王帅军 Wang Shuaijun, 吴炜 Wu Wei, and 杨晓敏 Yang Xiaomin. "Nonlinearity calibration incorporated with geometrical calibration for phase measuring profilometry." High Power Laser and Particle Beams 27, no. 7 (2015): 71005. http://dx.doi.org/10.3788/hplpb20152707.71005.

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3

Kajima, Mariko, Tsukasa Watanabe, Makoto Abe, and Toshiyuki Takatsuji. "Calibrator for 2D Grid Plate Using Imaging Coordinate Measuring Machine with Laser Interferometers." International Journal of Automation Technology 9, no. 5 (September 5, 2015): 541–45. http://dx.doi.org/10.20965/ijat.2015.p0541.

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A calibrator for 2D grid plates have been developed. The calibrator was based on a commercial imaging coordinate measuring machine (imaging CMM). A laser interferometer for the calibration of the x-coordinate and two laser interferometers for the calibration of the y-coordinate were attached to the imaging CMM. By applying multistep measurement method for the calibration procedure, the geometrical error in the calibrator was reduced. The calibration of a precision 2D grid plate was demonstrated, and the expanded uncertainty was estimated to be 0.2 μm (k =2).

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4

Nekouei Shahraki, M., and N. Haala. "INTRODUCING NOVEL GENERATION OF HIGH ACCURACY CAMERA OPTICAL-TESTING AND CALIBRATION TEST-STANDS FEASIBLE FOR SERIES PRODUCTION OF CAMERAS." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-1-W5 (December 11, 2015): 521–27. http://dx.doi.org/10.5194/isprsarchives-xl-1-w5-521-2015.

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The recent advances in the field of computer-vision have opened the doors of many opportunities for taking advantage of these techniques and technologies in many fields and applications. Having a high demand for these systems in today and future vehicles implies a high production volume of video cameras. The above criterions imply that it is critical to design test systems which deliver fast and accurate calibration and optical-testing capabilities. In this paper we introduce new generation of test-stands delivering high calibration quality in single-shot calibration of fisheye surround-view cameras. This incorporates important geometric features from bundle-block calibration, delivers very high (sub-pixel) calibration accuracy, makes possible a very fast calibration procedure (few seconds), and realizes autonomous calibration via machines. We have used the geometrical shape of a Spherical Helix (Type: 3D Spherical Spiral) with special geometrical characteristics, having a uniform radius which corresponds to the uniform motion. This geometrical feature was mechanically realized using three dimensional truncated icosahedrons which practically allow the implementation of a spherical helix on multiple surfaces. Furthermore the test-stand enables us to perform many other important optical tests such as stray-light testing, enabling us to evaluate the certain qualities of the camera optical module.

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Conte, Javier, Jorge Santolaria, Ana Cristina Majarena, Agustin Brau, and Juan Jose Aguilar Martín. "Laser Tracker Error Modeling and Kinematic Calibration Strategy." Key Engineering Materials 615 (June 2014): 63–69. http://dx.doi.org/10.4028/www.scientific.net/kem.615.63.

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Calibration of Laser Tracker systems is based most times in the determination of its geometrical errors. Some standards as the ASME B89.4.19 [1] and the VDI 2617-10 [2] describe different tests to calculate the geometric misalignments that cause systematic errors in Laser Tracker measurements. These errors are caused not only because of geometrical misalignments and other sources of error must also be taken in count. In this work we want to state the errors in a kinematic form. Errors will be split in two different components, geometric and kinematic errors. The first ones depend on the offsets, tilts and eccentricity of the mechanical and optical components of the system. Kinematic errors are different for every position of the Laser tracker, so they will be formulated as functions of three system variables: distance (R), vertical angle (V) and horizontal angle (H) usually called d, φ and θ. The goal of this work is to set up an evaluation procedure to determine geometric and kinematic errors of Laser Trackers.

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Yamazoe, Hirotake. "Geometrical and Temporal Calibration of Multiple Cameras Using Blinking Calibration Patterns." IPSJ Transactions on Computer Vision and Applications 6 (2014): 78–82. http://dx.doi.org/10.2197/ipsjtcva.6.78.

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7

Takatsuji, Toshiyuki, Sonko Osawa, and Tomizo Kurosawa. "Uncertainty analysis of calibration of geometrical gauges." Precision Engineering 26, no. 1 (January 2002): 24–29. http://dx.doi.org/10.1016/s0141-6359(01)00094-0.

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8

Beque, D., J. Nuyts, P. Suetens, and G. Bormans. "Optimization of geometrical calibration in pinhole SPECT." IEEE Transactions on Medical Imaging 24, no. 2 (February 2005): 180–90. http://dx.doi.org/10.1109/tmi.2004.839367.

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9

Bauer, M., D. Grießbach, A. Hermerschmidt, S. Krüger, M. Scheele, and A. Schischmanow. "Geometrical camera calibration with diffractive optical elements." Optics Express 16, no. 25 (November 24, 2008): 20241. http://dx.doi.org/10.1364/oe.16.020241.

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10

Liao, Che-Wei, Ming-Tzu Tsai, Heng-Li Huang, Lih-Jyh Fuh, Yen-Lin Liu, Zhi-Teng Su, and Jui-Ting Hsu. "Geometrical Calibration of a 2.5D Periapical Radiography System." Applied Sciences 10, no. 3 (January 30, 2020): 906. http://dx.doi.org/10.3390/app10030906.

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The objective of this study was to develop a geometrical calibration method applicable to the 2.5D prototype Periapical Radiography System and estimate component position errors. A two-steel-ball phantom with a precisely known position was placed in front of a digital X-ray sensor for two-stage calibration. In the first stage, the following three parameters were estimated: (1) r, the distance between the focal spot and the rotation axis of the X-ray tube; (2) ψ, the included angle between the straight line formed by the X-ray tube’s focal spot and rotation axis and the straight line of the orthogonal sensor; and (3) L4, the distance between the rotation axis and the plane where the two steel balls were positioned. In the second stage, the steel balls’ positions were determined to calculate the positions of the X-ray tube on the x, y, and z axes. Computer simulation was used to verify the accuracy of the calibration method. The results indicate that for the calibration approach proposed in this study, the differences between the estimated errors and setting errors were smaller than 0.15% in the first and second stages, which is highly accurate, verifying its applicability to accurate calibration of the 2.5D Periapical Radiography System.

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11

Simioni, Emanuele, Vania Da Deppo, Cristina Re, Alessandra Slemer, Maria Teresa Capria, Iacopo Ficai Veltroni, Donato Borrelli, et al. "SIMBIO-SYS/STC stereo camera calibration: Geometrical distortion." Review of Scientific Instruments 90, no. 4 (April 2019): 043106. http://dx.doi.org/10.1063/1.5085710.

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12

Renders, J. M., E. Rossignol, M. Becquet, and R. Hanus. "Kinematic calibration and geometrical parameter identification for robots." IEEE Transactions on Robotics and Automation 7, no. 6 (1991): 721–32. http://dx.doi.org/10.1109/70.105381.

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13

Xiao, Yong-Liang, Xianyu Su, and Wenjing Chen. "Flexible geometrical calibration for fringe-reflection 3D measurement." Optics Letters 37, no. 4 (February 10, 2012): 620. http://dx.doi.org/10.1364/ol.37.000620.

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14

Ardakani, H. K., A. Mousavinia, and Farzad Safaei. "Four points: one-pass geometrical camera calibration algorithm." Visual Computer 36, no. 2 (January 23, 2019): 413–24. http://dx.doi.org/10.1007/s00371-019-01632-7.

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15

Lin, Psang Dain, and Chi-Kuen Sung. "Camera Calibration Based on Snell’s Law." Journal of Dynamic Systems, Measurement, and Control 128, no. 3 (August 24, 2005): 548–57. http://dx.doi.org/10.1115/1.2192824.

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In this paper we present a camera calibration method using Snell’s Law. Traditional camera calibration is based on the pinhole model, which is an approximation algorithm using untrue geometrical assumptions and giving a single lumped result for the various optical elements in the camera system. Using full modeling of lens geometry, the proposed method establishes the geometric relationship between images and objects via Snell’s Law. A matrix equation that relates the intrinsic/extrinsic parameters of image the plane and six pose parameters of each element is determined from sensitivity analysis. These parameters can be identified using the least square method by observing points with known coordinates. An illustrative example using a two-camera stereo coordinate measurement system demonstrates that system performance via the proposed method is better than the pinhole model.

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Lanquart, J. P. "Effect of the geometrical parameters on an absolute calibration." Journal of Physics D: Applied Physics 19, no. 11 (November 14, 1986): 2043–49. http://dx.doi.org/10.1088/0022-3727/19/11/004.

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17

Ma, Tianyu, Yinbin Miao, Rutao Yao, Tiantian Dai, and Xiao Deng. "Quantitative accuracy assessment and optimization of SPECT geometrical calibration." Tsinghua Science and Technology 15, no. 1 (February 2010): 96–101. http://dx.doi.org/10.1016/s1007-0214(10)70015-8.

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18

Chen, Mianyi, Yan Xi, Wenxiang Cong, Baodong Liu, Biao Wei, and Ge Wang. "X-ray CT geometrical calibration via locally linear embedding." Journal of X-Ray Science and Technology 24, no. 2 (March 25, 2016): 241–56. http://dx.doi.org/10.3233/xst-160548.

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19

Ecorchard, Gaël, Reimund Neugebauer, and Patrick Maurine. "Elasto-geometrical modeling and calibration of redundantly actuated PKMs." Mechanism and Machine Theory 45, no. 5 (May 2010): 795–810. http://dx.doi.org/10.1016/j.mechmachtheory.2009.12.008.

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20

Díaz, Jesús Díaz, Jenny Stritzel, Maik Rahlves, Omid Majdani, Eduard Reithmeier, Tobias Ortmaier, and Bernhard Roth. "One step geometrical calibration method for optical coherence tomography." Journal of Optics 18, no. 1 (December 1, 2015): 015301. http://dx.doi.org/10.1088/2040-8978/18/1/015301.

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21

Jeong, Jay il, Dongsoo Kang, Young Man Cho, and Jongwon Kim. "Kinematic Calibration for Redundantly Actuated Parallel Mechanisms." Journal of Mechanical Design 126, no. 2 (March 1, 2004): 307–18. http://dx.doi.org/10.1115/1.1667902.

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We present a new kinematic calibration algorithm for redundantly actuated parallel mechanisms, and illustrate the algorithm with a case study of a planar seven-element 2-degree-of-freedom (DOF) mechanism with three actuators. To calibrate a nonredundantly actuated parallel mechanism, one can find actual kinematic parameters by means of geometrical constraint of the mechanism’s kinematic structure and measurement values. However, the calibration algorithm for a nonredundant case does not apply for a redundantly actuated parallel mechanism, because the angle error of the actuating joint varies with position and the geometrical constraint fails to be consistent. Such change of joint angle error comes from constraint torque variation with each kinematic pose (meaning position and orientation). To calibrate a redundant parallel mechanism, one therefore has to consider constraint torque equilibrium and the relationship of constraint torque to torsional deflection, in addition to geometric constraint. In this paper, we develop the calibration algorithm for a redundantly actuated parallel mechanism using these three relationships, and formulate cost functions for an optimization algorithm. As a case study, we executed the calibration of a 2-DOF parallel mechanism using the developed algorithm. Coordinate values of tool plate were measured using a laser ball bar and the actual kinematic parameters were identified with a new cost function of the optimization algorithm. Experimental results showed that the accuracy of the tool plate improved by 82% after kinematic calibration in a redundant actuation case.

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22

Douet, Jules, Jing Xu, and Ken Chen. "Sphere-Based Geometrical Calibration Method for Structured Light Surface Measurement Systems." Advanced Materials Research 571 (September 2012): 433–38. http://dx.doi.org/10.4028/www.scientific.net/amr.571.433.

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This paper proposes a sphere-based calibration method for the structured light system with unconstrained one projector & one camera, regardless of pattern codification. A 1-pose example of such a method is also proposed and tested. In comparison with a traditional plane translation method of 15 poses, we note an increase in the consistency of more than 10% while the calibration time shrinks to 6% and the calibration accessory is reduced to the size of a flash-light. This method suits well for applications where mobility, speed and ease-of-use are important criteria.

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23

Zaiter, Mohammad Ali, Régis Lherbier, Ghaleb Faour, Oussama Bazzi, and Jean-Charles Noyer. "Extrinsic LiDAR/Ground Calibration Method Using 3D Geometrical Plane-Based Estimation." Sensors 20, no. 10 (May 16, 2020): 2841. http://dx.doi.org/10.3390/s20102841.

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This paper details a new extrinsic calibration method for scanning laser rangefinder that is precisely focused on the geometrical ground plane-based estimation. This method is also efficient in the challenging experimental configuration of a high angle of inclination of the LiDAR. In this configuration, the calibration of the LiDAR sensor is a key problem that can be be found in various domains and in particular to guarantee the efficiency of ground surface object detection. The proposed extrinsic calibration method can be summarized by the following procedure steps: fitting ground plane, extrinsic parameters estimation (3D orientation angles and altitude), and extrinsic parameters optimization. Finally, the results are presented in terms of precision and robustness against the variation of LiDAR’s orientation and range accuracy, respectively, showing the stability and the accuracy of the proposed extrinsic calibration method, which was validated through numerical simulation and real data to prove the method performance.

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24

ZHENG, ZHIGANG, ZHENGJUN ZHA, LONG HAN, and ZENGFU WANG. "FEATURE DETECTION AND CORRESPONDENCE FOR CAMERA CALIBRATION." International Journal of Information Acquisition 05, no. 01 (March 2008): 41–50. http://dx.doi.org/10.1142/s021987890800148x.

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This paper addresses the problem of highly accurate, highly speedy, more reliable and fully automatic camera calibration. Our objective is to construct a reliable and fully automatic system to supply a more robust and highly accurate calibration scheme. A checkerboard pattern is used as calibration pattern. After the corner points on image are detected, an improved Delaunay triangulation based algorithm is used to make correspondences between corner points on image and corner points on checkerboard in 3D space. In order to determine precise position of the actual corner points, a geometrical constraint based global curve fitting algorithm has been developed. The experimental results show that the geometrical constraint based method can improve remarkably the performance of the feature detection and camera calibration.

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25

Ali, Salah H. R., and Ihab H. Naeim. "Uncertainty Estimation due to Geometrical Imperfection and Wringing in Calibration of End Standards." ISRN Optics 2013 (September 18, 2013): 1–8. http://dx.doi.org/10.1155/2013/697176.

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Uncertainty in gauge block measurement depends on three major areas, thermal effects, dimension metrology system that includes measurement strategy, and end standard surface perfection grades. In this paper, we focus precisely on estimating the uncertainty due to the geometrical imperfection of measuring surfaces and wringing gab in calibration of end standards grade 0. Optomechanical system equipped with Zygo measurement interferometer (ZMI-1000A) and AFM technique have been employed. A novel protocol of measurement covering the geometric form of end standard surfaces and wrung base platen was experimentally applied. Surface imperfection characteristics of commonly used 6.5 mm GB have been achieved by AFM in 2D and 3D to be applied in three sets of experiments. The results show that there are obvious mapping relations between the geometrical imperfection and wringing thickness of the end standards calibration. Moreover, the predicted uncertainties are clearly estimated within an acceptable range from 0.132 µm, 0.164 µm and 0.202 µm, respectively. Experimental and analytical results are also presented.

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Wen, Xiulan, Shun He, GuiFang Qiao, Dongxia Wang, Aiguo Song, ChuanShuai Kang, and Zhongyan Lv. "Uncertainty Estimation of Robot Geometric Parameters and End-Effecter Position Based on New Generation GPS." Mathematical Problems in Engineering 2019 (June 9, 2019): 1–11. http://dx.doi.org/10.1155/2019/7830489.

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The robot end-effecter positioning accuracy can be improved by the calibration of robot geometric parameters errors. According to the requirements of new generation geometrical product specification (GPS), the calibration uncertainty should be given when the calibration results are given. In this paper, the modified Denavit-Hartenberg method (MDH) of six-joint series robot is established and the joint movement trajectory method is applied to calibrate the robot geometric parameters. The uncertainty contributors significant are analyzed and the calibration uncertainty of robot geometric parameters is estimated based on the guide to the expression of uncertainty in measurement (GUM). In order to overcome the limitations of GUM for highly nonlinear model and reduce computational cost based on Monte Carlo Simulation (MCS) error estimation, an adaptive MCS (AMCS) is proposed to estimate the uncertainty distribution of robot end-effector position. Simulation and practical example are illustrated and the experiments results confirm that not only can the proposed method evaluate the calibration uncertainty of geometric parameters, but also the uncertainty distribution of end-effecter positions in the whole robot workspace can be estimated by AMCS in which the number of MCS trials can be selected adaptively and the quality of the numerical results can be controlled directly. The proposed method not only can evaluate the uncertainty of six-joint series robot geometric parameters and end-effecter position rapidly and accurately, but also can be popularized to the estimation of calibration uncertainty of other kinds of robot geometric parameters.

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27

Schrijver, Hans. "Calibration and Characteristics of the HIPPARCOS Payload." Highlights of Astronomy 9 (1992): 401–4. http://dx.doi.org/10.1017/s1539299600009308.

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AbstractThe Hipparcos geometrical calibrations directly linked with the astrometrical precision are shortly described, and their accuracies given. An example for the basic angle shows the very high stability of the instrument.

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28

Khoury, R., A. Bonissent, J. C. Clémens, C. Meessen, E. Vigeolas, M. Billault, and C. Morel. "A geometrical calibration method for the PIXSCAN micro-CT scanner." Journal of Instrumentation 4, no. 07 (July 27, 2009): P07016. http://dx.doi.org/10.1088/1748-0221/4/07/p07016.

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29

Kamali, Kaveh, and Ilian A. Bonev. "Optimal Experiment Design for Elasto-Geometrical Calibration of Industrial Robots." IEEE/ASME Transactions on Mechatronics 24, no. 6 (December 2019): 2733–44. http://dx.doi.org/10.1109/tmech.2019.2944428.

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Walker, D. K., and D. F. Williams. "Compensation for geometrical variations in coplanar waveguide probe-tip calibration." IEEE Microwave and Guided Wave Letters 7, no. 4 (April 1997): 97–99. http://dx.doi.org/10.1109/75.563631.

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31

Pilch, Adam. "Optimization-based method for the calibration of geometrical acoustic models." Applied Acoustics 170 (December 2020): 107495. http://dx.doi.org/10.1016/j.apacoust.2020.107495.

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32

Ouyang, Shi, You, and Zhao. "Extrinsic Parameter Calibration Method for a Visual/Inertial Integrated System with a Predefined Mechanical Interface." Sensors 19, no. 14 (July 12, 2019): 3086. http://dx.doi.org/10.3390/s19143086.

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For a visual/inertial integrated system, the calibration of extrinsic parameters plays a crucial role in ensuring accurate navigation and measurement. In this work, a novel extrinsic parameter calibration method is developed based on the geometrical constraints in the object space and is implemented by manual swing. The camera and IMU frames are aligned to the system body frame, which is predefined by the mechanical interface. With a swinging motion, the fixed checkerboard provides constraints for calibrating the extrinsic parameters of the camera, whereas angular velocity and acceleration provides constraints for calibrating the extrinsic parameters of the IMU. We exploit the complementary nature of both the camera and IMU, of which the latter assists in the checkerboard corner detection and correction while the former suppresses the effects of IMU drift. The results of the calibration experiment reveal that the extrinsic parameter accuracy reaches 0.04° for each Euler angle and 0.15 mm for each position vector component (1σ).

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Simioni, E., C. Pernechele, C. Re, L. Lessio, and G. Cremonese. "GEOMETRICAL CALIBRATION FOR THE PANROVER: A STEREO OMNIDIRECTIONAL SYSTEM FOR PLANETARY ROVER." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B3-2020 (August 21, 2020): 1151–58. http://dx.doi.org/10.5194/isprs-archives-xliii-b3-2020-1151-2020.

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Abstract. A novel panoramic stereo imaging system is proposed in this paper. The system is able to carry out a 360° stereoscopic vision, useful for rover autonomous-driving, and capture simultaneously a high-resolution stereo scene. The core of the concept is a novel "bifocal panoramic lens" (BPL) based on hyper hemispheric model (Pernechele et al. 2016). This BPL is able to record a panoramic field of view (FoV) and, simultaneously, an area (belonging to the panoramic FoV) with a given degree of magnification by using a unique image sensor. This strategy makes possible to avoid rotational mechanisms. Using two BPLs settled in a vertical baseline (system called PANROVER) allows the monitoring of the surrounding environment in stereoscopic (3D) mode and, simultaneously, capturing an high-resolution stereoscopic images to analyse scientific cases, making it a new paradigm in the planetary rovers framework.Differently from the majority of the Mars systems which are based on rotational mechanisms for the acquisition of the panoramic images (mosaicked on ground), the PANROVER does not contain any moving components and can rescue a hi-rate stereo images of the context panorama.Scope of this work is the geometric calibration of the panoramic acquisition system by the omnidirectional calibration methods (Scaramuzza et al. 2006) based on Zhang calibration grid. The procedures are applied in order to obtain well rectified synchronized stereo images to be available for 3D reconstruction. We applied a Zhang chess boards based approach even during STC/SIMBIO-SYS stereo camera calibration (Simioni et al. 2014, 2017). In this case the target of the calibration will be the stereo heads (the BPLs) of the PANROVER with the scope of extracting the intrinsic parameters of the optical systems. Differently by previous pipelines, using the same data bench the estimate of the extrinsic parameters is performed.

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Mélykuti, B., and E. J. Kruck. "Camera Calibration with Radial Variance Component Estimation." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-1 (November 7, 2014): 253–56. http://dx.doi.org/10.5194/isprsarchives-xl-1-253-2014.

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Camera calibration plays a more and more important role in recent times. Beside real digital aerial survey cameras the photogrammetric market is dominated by a big number of non-metric digital cameras mounted on UAVs or other low-weight flying platforms. The in-flight calibration of those systems has a significant role to enhance the geometric accuracy of survey photos considerably. It is expected to have a better precision of photo measurements in the center of images then along the edges or in the corners. With statistical methods the accuracy of photo measurements in dependency of the distance of points from image center has been analyzed. This test provides a curve for the measurement precision as function of the photo radius. A high number of camera types have been tested with well penetrated point measurements in image space. The result of the tests led to a general consequence to show a functional connection between accuracy and radial distance and to give a method how to check and enhance the geometrical capability of the cameras in respect to these results.

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Gektin, U. M., N. A. Egoshkin, V. V. Eremeev, A. E. Kuznetcov, and A. M. Kochergin. "PRELAUNCH PHOTOGRAMMETRIC CALIBRATION OF RUSSIAN SATELLITE ELEKTRO-L IMAGERY INSTRUMENTS." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B6 (June 17, 2016): 161–63. http://dx.doi.org/10.5194/isprsarchives-xli-b6-161-2016.

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Technology of prelaunch geometric calibration of multispectral imagery instruments of Russian geostationary satellites “Elektro-L” No.1 and No.2 is considered. Circular control points are used as a test field. Its geometrical model is developed to take distortions in the collimator optical system into account. Multiple observations of a test field at different angles is used to cover the full visual field of a geostationary sensor. New algorithm of circular control point detection is developed and adapted to complex geometry of geostationary imagery. It is capable of processing images formed as a set of separate scans. Under calibration, sensor design parameters and also the law of scanning mirror motion are specified. The paper contains results of the technology approval under prelaunch calibration of MSU-GS sensors for geostationary operational meteorological satellites (GOMS) “Elektro-L” No.1 and No.2.

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Gektin, U. M., N. A. Egoshkin, V. V. Eremeev, A. E. Kuznetcov, and A. M. Kochergin. "PRELAUNCH PHOTOGRAMMETRIC CALIBRATION OF RUSSIAN SATELLITE ELEKTRO-L IMAGERY INSTRUMENTS." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B6 (June 17, 2016): 161–63. http://dx.doi.org/10.5194/isprs-archives-xli-b6-161-2016.

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Technology of prelaunch geometric calibration of multispectral imagery instruments of Russian geostationary satellites “Elektro-L” No.1 and No.2 is considered. Circular control points are used as a test field. Its geometrical model is developed to take distortions in the collimator optical system into account. Multiple observations of a test field at different angles is used to cover the full visual field of a geostationary sensor. New algorithm of circular control point detection is developed and adapted to complex geometry of geostationary imagery. It is capable of processing images formed as a set of separate scans. Under calibration, sensor design parameters and also the law of scanning mirror motion are specified. The paper contains results of the technology approval under prelaunch calibration of MSU-GS sensors for geostationary operational meteorological satellites (GOMS) “Elektro-L” No.1 and No.2.

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Cramer, M., H. J. Przybilla, and A. Zurhorst. "UAV CAMERAS: OVERVIEW AND GEOMETRIC CALIBRATION BENCHMARK." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W6 (August 23, 2017): 85–92. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w6-85-2017.

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Different UAV platforms and sensors are used in mapping already, many of them equipped with (sometimes) modified cameras as known from the consumer market. Even though these systems normally fulfil their requested mapping accuracy, the question arises, which system performs best? This asks for a benchmark, to check selected UAV based camera systems in well-defined, reproducible environments. Such benchmark is tried within this work here. Nine different cameras used on UAV platforms, representing typical camera classes, are considered. The focus is laid on the geometry here, which is tightly linked to the process of geometrical calibration of the system. In most applications the calibration is performed in-situ, i.e. calibration parameters are obtained as part of the project data itself. This is often motivated because consumer cameras do not keep constant geometry, thus, cannot be seen as metric cameras. Still, some of the commercial systems are quite stable over time, as it was proven from repeated (terrestrial) calibrations runs. Already (pre-)calibrated systems may offer advantages, especially when the block geometry of the project does not allow for a stable and sufficient in-situ calibration. Especially for such scenario close to metric UAV cameras may have advantages. Empirical airborne test flights in a calibration field have shown how block geometry influences the estimated calibration parameters and how consistent the parameters from lab calibration can be reproduced.

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Escobar-Corral, N., C. Bornemann, S. Lotze, A. Schmachtenberg, A. Stahl, and M. J. Eble. "EP-1132: Geometrical calibration of a Monte Carlo simulated linear accelerator." Radiotherapy and Oncology 106 (March 2013): S427. http://dx.doi.org/10.1016/s0167-8140(15)33438-1.

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Ferrucci, Massimiliano, Richard K. Leach, Claudiu Giusca, Simone Carmignato, and Wim Dewulf. "Towards geometrical calibration of x-ray computed tomography systems—a review." Measurement Science and Technology 26, no. 9 (August 19, 2015): 092003. http://dx.doi.org/10.1088/0957-0233/26/9/092003.

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Yuan, Ting, Feng Zhang, Xiaoping Tao, Xuejun Zhang, and Run Zhou. "Flexible geometrical calibration for fringe-reflection optical three-dimensional shape measurement." Applied Optics 54, no. 31 (October 23, 2015): 9102. http://dx.doi.org/10.1364/ao.54.009102.

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El Bitar, Z., R. H. Huesman, R. Boutchko, Virgile Bekaert, David Brasse, and G. T. Gullberg. "A detector response function design in pinhole SPECT including geometrical calibration." Physics in Medicine and Biology 58, no. 7 (March 15, 2013): 2395–411. http://dx.doi.org/10.1088/0031-9155/58/7/2395.

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Chen, Bei-shi, Qing Zhong, Hai-feng Li, Xu Liu, and Hai-song Xu. "Automatic geometrical calibration for multiprojector-type light field three-dimensional display." Optical Engineering 53, no. 7 (July 28, 2014): 073107. http://dx.doi.org/10.1117/1.oe.53.7.073107.

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Giusca, C. L., R. K. Leach, F. Helery, and T. Gutauskas. "Calibration of the geometrical characteristics of areal surface topography measuring instruments." Journal of Physics: Conference Series 311 (August 19, 2011): 012005. http://dx.doi.org/10.1088/1742-6596/311/1/012005.

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Wang, Daodang, Yongying Yang, Chen Chen, and Yongmo Zhuo. "Calibration of geometrical systematic error in high-precision spherical surface measurement." Optics Communications 284, no. 16-17 (August 2011): 3878–85. http://dx.doi.org/10.1016/j.optcom.2011.04.051.

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Xiao, Yong-Liang, Xianyu Su, and Zhisheng You. "Pose transfer geometrical calibration for fringe-reflection optical three-dimensional measurement." Optics Communications 305 (September 2013): 143–46. http://dx.doi.org/10.1016/j.optcom.2013.04.060.

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Fassi, Irene, and Giovanni Legnani. "Hand to sensor calibration: A geometrical interpretation of the matrix equation." Journal of Robotic Systems 22, no. 9 (2005): 497–506. http://dx.doi.org/10.1002/rob.20082.

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Rougée, Anne, Catherine Picard, Cyril Ponchut, and Yves Trousset. "Geometrical calibration of x-ray imaging chains for three-dimensional reconstruction." Computerized Medical Imaging and Graphics 17, no. 4-5 (July 1993): 295–300. http://dx.doi.org/10.1016/0895-6111(93)90020-n.

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Zhang, Zhi Xian, Li Liang, and Yong Deng. "Camera Calibration Method Based on Halcon." Applied Mechanics and Materials 385-386 (August 2013): 518–22. http://dx.doi.org/10.4028/www.scientific.net/amm.385-386.518.

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Abstract:

Aiming at the applications of computer vision,a nonlinear image geometrical model for array CCD camera was build and the interior parameters and exterior parameters as well were analyzed.By applying Halcon calibration board with circular targets plane of matrix gridding type and functions library,a camera calibration algorithm and accuracy analysis were given.Experiments indicated that the parameters were accurate and this method is simple and it improves the calibration precision and computation speed, and has a good cross-platform portability.

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Sobolevski, Enrique Garcia, Andreas Nau, and Berthold Scholtes. "Residual Stress Analysis Using the Hole-Drilling Method and Geometry-Specific Calibration Functions." Materials Science Forum 681 (March 2011): 159–64. http://dx.doi.org/10.4028/www.scientific.net/msf.681.159.

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Due to the fact that no analytical solution exists to determine residual stresses in components with geometrical deviations from an ideal plate with the well known semi-destructive incremental hole-drilling method, calibration functions are required. Currently, such available functions, generated in an experimental or numerical manner are strictly speaking only valid for the reference case of a wide and thick plate and are only applicable if the surrounding field of the geometry at the measurement point is similar to the ideal one. Consequently, accuracy and reliability of assessing residual stresses by means of the incremental hole-drilling method can be improved if geometry specific calibration functions adapted to real geometries are used. This work deals with the determination of specific calibration functions by means of numerical simulations according to the MPA II standard (differential method) for three different components, violating the geometric restrictions of the reference.

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Zhang, Xi, Yuanzhi Xu, Haichao Li, Lijing Zhu, Xin Wang, and Wei Li. "Flexible method for accurate calibration of large-scale vision metrology system based on virtual 3-D targets and laser tracker." International Journal of Advanced Robotic Systems 16, no. 6 (November 1, 2019): 172988141989351. http://dx.doi.org/10.1177/1729881419893516.

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For the purpose of obtaining high-precision in stereo vision calibration, a large-size precise calibration target, which can cover more than half of the field of view is vital. However, large-scale calibration targets are very difficult to fabricate. Based on the idea of error tracing, a high-precision calibration method for vision system with large field of view by constructing a virtual 3-D calibration target with a laser tracker was proposed in this article. A virtual 3-D calibration target that covers the whole measurement space can be established flexibly and the measurement precision of the vision system can be traceable to the laser tracker. First, virtual 3-D targets by calculating rigid body transformation with unit quaternion method were constructed. Then, the high-order distortion camera model was taken into consideration. Besides, the calibration parameters were solved with Levenberg–Marquardt optimization algorithm. In the experiment, a binocular stereo vision system with the field of view of 4 × 3 × 2 m3 was built for verifying the validity and precision of the proposed calibration method. It is measured that the accuracy with the proposed method can be greatly improved comparing with traditional plane calibration method. The method can be widely used in industrial applications, such as in the field of calibrating large-scale vision-based coordinate metrology, and six-degrees of freedom pose tracking system for dimensional measurement of workpiece, as well as robotics geometrical accuracy detection and compensation.

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