Détail de l'indexation
35.00 Télédétection - généralitésOuvrages de la bibliothèque en indexation 35.11 (14)
Ajouter le résultat dans votre panier Affiner la recherche Interroger des sources externesInvestigations of high precision terrestrial laser scanning with emphasis on the development of a robust close-range 3D-laser scanning system / Hans Martin Zogg (2008)
Titre : Investigations of high precision terrestrial laser scanning with emphasis on the development of a robust close-range 3D-laser scanning system Type de document : Thèse/HDR Auteurs : Hans Martin Zogg, Auteur Editeur : Zurich : Institut für Geodäsie und Photogrammetrie IGP - ETH Année de publication : 2008 Collection : IGP Mitteilungen, ISSN 0252-9335 num. 098 Importance : 171 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-906467-78-8 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] acquisition d'images
[Termes IGN] données localisées 3D
[Termes IGN] étalonnage d'instrument
[Termes IGN] lever souterrain
[Termes IGN] modélisation géométrique de prise de vue
[Termes IGN] précision géométrique (imagerie)
[Termes IGN] semis de points
[Termes IGN] télémètre laser terrestre
[Termes IGN] télémétrie laser terrestreIndex. décimale : 35.11 Géométrie et qualité des prises de vues Résumé : (Auteur) In recent years, numerous measurement systems and techniques have become available on the market for three-dimensional (3D) surveying of objects. Largely due to the increasing need of 3D-data, fast area-wide 3D-measurement methods are in high demand. In the world of surveying and the field of engineering geodesy, terrestrial laser scanning has been established as a newer measurement method for fast, area-wide SD-surveying. Terrestrial laser scanners measure distances and angles to objects without any contact. The actual geometry information of the scanned object has to be derived from a resulting 3D-point cloud in post-processing.
After the initial hype of terrestrial laser scanning, a slight disillusionment set in. Projects were not profitable or failed due to insufficient knowledge about laser scanning technology and its specifics. In addition, the hardware and software products available on the market often do not meet the requirements of specific applications. Thus, the selection of convenient applications for a particular terrestrial laser scanning system, the sensitivity in terms of environmental conditions, or the extensive post-processing of laser scanning data are just a few of the difficulties in using laser scanning technology. As a result, terrestrial laser scanning is rarely used for projects in engineering geodesy. Even though terrestrial laser scanning offers great potential, new fields of application have yet to be investigated.
This thesis originated from a project addressing the development of a qualified measurement system based on terrestrial laser scanning for the surveying of underground utility caverns in the field of water and sewage engineering. There was no convenient measurement system available on the market when the project started in 2005. There are three main objectives of this thesis: the development of a cost-efficient robust close-range 3D-laser scanning system largely for surveying underground utility caverns, the calibrations and investigations of terrestrial laser scanners with focus on the newly developed measurement system, and the development of new fields of application for terrestrial laser scanning. Moreover, this thesis contributes to the area of terrestrial laser scanning by offering better knowledge on its integration into engineering geodesy.
For the hardware development, the 2D-laser scanner SICK LMS200-30106 by Sick AG was selected and implemented as a distance measurement unit measuring distances and angles. This unit is well known and established in industrial applications and in the field of robotics. In addition, all components that were used for the close-range 3D-laser scanning system were selected according to predefined requirements. These requirements were strongly related to the application of the measurement of underground utility caverns. Furthermore, this thesis shows that an appropriate calibration of the close-range 3D-laser scanning system - the distance measurement unit specifically - allows its application in the field of engineering geodesy. Thus, appropriate calibration routines were developed, and intensive additional investigations of the measurement systems enabled the verification of the measurement accuracy and performance.
The close-range terrestrial 3D-laser scanner ZLS07 resulted from the development of a 3D-measurement system based on the terrestrial laser scanning technology. The ZLS07 is a robust and reliable measurement system that fulfils the requirements focused on surveying of underground utility caverns. Its specific limitations lie in the measurement range, accuracy, and angular resolution. However, the ZLS07 has been successfully established as a new measurement instrument at the surveying department of the city of Zurich. In addition to the hardware developments, an approach for automatic geometry modelling from 3D-point clouds was developed, tested, and discussed for post-processing 3D-point clouds of underground utility caverns. Furthermore, the ZLS07 was successfully used in other applications, such as the damage detection of an incinerator or the reverse engineering of technical constructions.Note de contenu : 1 Introduction
1.1 Motivation
1.2 Aims of the Thesis.
1.3 Outline
2 High Precision Terrestrial Laser Scanning
2.1 Terrestrial Laser Scanning in Engineering Geodesy
2.2 Specifications of Terrestrial Laser Scanners
2.3 The Measurement System "Terrestrial Laser Scanner"
2.4 Applications of Terrestrial Laser Scanning.
2.5 Remarks.
3 Development of Terrestrial Laser Scanner ZLS07
3.1 Requirements
3.2 Components of the ZLS07
3.3 Configuration of Terrestrial Laser Scanner ZLS07
3.4 Measurement Coordinate Systems
3.5 Software
3.6 Result of a Scan
3.7 Discussion
4 Calibration of Terrestrial Laser Scanner ZLSO 7
4.1 Calibration of Geodetic Sensors
4.2 Distance Measurement Unit
4.3 Errors of Axes
4.4 Synchronisation of Rotation Table and Distance Measurement Unit
4.5 Review
5 Validation of Terrestrial Laser Scanner ZLS07
5.1 Angle Measurement System
5.2 Wobbling of Vertical Axis
5.3 3D-Measurement Quality
5.4 Review
6 Acquisition of Underground Utility Caverns
6.1 Overview
6.2 ZLS07 for Acquisition of Underground Utility Caverns
6.3 Data Post-Processing Workflow
6.4 Review
7 Automatic Geometry Modelling
7.1 Data Modelling Requirements
7.2 Previous Work
7.3 Development of an Approach for Automatic Cavern Detection
7.4 Results
7.5 Review
8 Various Applications for Terrestrial Laser Scanner ZLS07
8.1 Damage Detection of an Incinerator
8.2 Reverse Engineering at the Overflow Construction of Nalps Dam (CH).
8.3 Review
9 Summary
9.1 Conclusions
9.2 Outlook
References
A Appendix
A. 1 Rotation Table ETH Zurich.
A.2 Software
A.3 Fourier-SeriesNuméro de notice : 15459 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse étrangère DOI : 10.3929/ethz-a-005679006 En ligne : http://dx.doi.org/10.3929/ethz-a-005679006 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=62725 Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 15459-01 35.11 Livre Centre de documentation En réserve M-103 Disponible
Titre : Range imaging : investigation, calibration and development Type de document : Thèse/HDR Auteurs : Timo Kahlmann, Auteur Editeur : Zurich : Institut für Geodäsie und Photogrammetrie IGP - ETH Année de publication : 2008 Collection : IGP Mitteilungen, ISSN 0252-9335 num. 097 Importance : 142 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-906467-72-6 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] acquisition d'images
[Termes IGN] angle d'incidence
[Termes IGN] caméra numérique
[Termes IGN] capteur imageur
[Termes IGN] données localisées 3D
[Termes IGN] étalonnage de chambre métrique
[Termes IGN] mesurage de distances
[Termes IGN] métrologieIndex. décimale : 35.11 Géométrie et qualité des prises de vues Résumé : (Auteur) In recent years, numerous sensor systems for the capturing of three-dimensional environments and objects have become available. Besides laser scanners and geodetic total stations, stereo vision and triangulation-based systems have to be exemplarily named here. Especially laser scanners have beco-me state-of-the-art regarding speed and accuracy with respect to their ability to acquire objects up to a size of several tens of meters. A main drawback of laser scanners is their sequential mode of operation. They measure point by point. A few years ago, a new technology was developed to full functionality which is able to capture the environment simultaneously with a high resolution. So-called range imaging (RIM) or flash ladar cameras, which are based on digital imaging technology, merged with the ability to measure the distance to the corresponding object point in each pixel. Distance measurement is either based on the direct or indirect Time-of-Flight principle. Due to its parallel acquisition with up to video frame rate, RIM cameras are even able to capture moving objects. With respect to the optical dependencies, 3-D coordinates of the captured scene are derived. The nominal precision of the distance measurement is a few millimeters. RIM could become the technology of choice for many applications if the properties and characteristics become stable and predictable. Automotive, robotics, and safety systems can be named, for example. Significant deviations between nominal and measured coordinates occur in a range of several centimeters. Only intensive investigations can help to reach the theoretical limitations here.
This thesis deals with several aspects which affect the measurements of RIM cameras. First, a short introduction into the basic technologies that are associated with RIM is presented. Besides imaging and distance measurement methods, two basic principles of RIM are distinguished. Furthermore, the focus is laid on the specific limitations. During this work three different cameras have become available: the SwissRanger SR-2 and the SR-3000 from CSEM / MESA Imaging (Switzerland) and later on the 3k-S from PMDtec (Germany). These three cameras are based on the indirect Time-of-Flight principle and are equipped with different sophisticated features. Besides integrated calibration and correction functionality, the suppression of background illumination is one of the main features. However, these cameras are only intended to be highly developed demonstrators. An adaption to the specific application areas, like automotive or robotics, leads to specialized properties according to the desired claims.
The analysis of the existing camera types helps to understand the technology more closely. The raw data of the analyzed cameras is not more accurate than a few centimeters. In order to investigate the properties of the available cameras, special experimental setups had to be developed. The main part of this work deals with the investigation and calibration of the components of RIM cameras. The geometrical deviations of the optical system are addressed by means of a photogrammetric camera calibration. The distance measurement system is analyzed with respect to the deviations and statistics. Thus, limitations of both precision and accuracy are indicated. Besides the influences of the scattering effect, integration time, emitting system, and angle of incidence, target reflectivity, external and internal temperature, and finally linearity and fixed-pattern noise are discussed. Further on, an approach for a system calibration process is presented. Due to the complexity of the influencing parameters, a complete correction of the measurement data with respect to the diverse influencing parameters has not been reached. But the highly systematic dependencies promise sophisticated calibration routines in the future. This work contributes to the understanding of the sensors.
Nevertheless, the investigated influences of temperature on the distance measurement accuracy, which is indicated as a measure for the deviation between true and nominal value, have been significantly reduced by an uncoupling of the distance measurement and the external and internal temperature by means of a relative measurement setup. The introduction of an internal reference light path helps to reduce the temperature's influence on the distance data to a large degree. The experimental setup and the proof of the functionality complete this work.
The results of the numerous investigations will help to increase the accuracy of RIM cameras, especially vital for several applications, in need of improved accuracies. It has been shown that the theoretical limits lie within reach with help of suitably sophisticated calibration procedures.Note de contenu : 1 Introduction
1.1 Motivation
1.1.1 Application: Tracking of People in Indoor Environments
1.1.2 Application: Automotive
1.2 Aims of This Thesis
1.3 Structure
2 3-D Range Imaging Camera Technology
2.1 Distance Measurement
2.1.1 Time-of-Flight Distance Measurement
2.1.2 Phase-Difference Distance Measurement
2.1.2.1 Working Principle
2.1.2.2 Characteristics and Limitations
2.2 Imaging Technology
2.2.1 Charge Collection
2.2.2 Charge Transfer and Quantification
2.3 Range Imaging Sensors and Realizations
2.3.1 Combined CCD/CMOS Technology
2.3.2 Photonic Mixer Device (PMD) in CMOS Technology
2.3.3 Arrays of Single Photon Avalanche Diodes in CMOS Technology
2.3.4 Shuttered Time-of-Flight
2.4 3-D Coordinate Measurement Principle
3 Investigation and Calibration
3.1 Definitions
3.2 Photogrammetric Camera Calibration
3.2.1 SR-2
3.2.2 SR-3000
3.3 Distance Measurement
3.3.1 Scattering
3.3.2 Integration Time
3.3.3 Statistics
3.3.4 Emitting System (LEDs)
3.3.5 Target Reflectivity
3.3.6 Angle of Incidence
3.3.7 Temperature
3.3.8 Distance / Linearity
3.3.9 Fixed-Pattern Noise
3.3.10 Mixed Pixel
3.4 Integral RIM Camera Calibration
3.5 Conclusion
4 Implementation of an Internal Reference
4.1 Theory
4.2 Implementation: ETH Solution
4.3 Validation
4.3.1 Warm Up
4.3.2 External Temperature
4.3.2.1 Experiment 1: Temperature Variation and Long-Term Acclimatization
4.3.2.2 Experiment 2: Extreme Temperatures
4.3.2.3 Experiment 3: Two External Distances
4.4 Conclusion and Outlook
5 Conclusions
5.1 Summary
5.2 Outlook
Appendix
A SwissRanger SR-2 Specifications
B SwissRanger SR-3000 Specifications
C Photogrammetric Calibration Results for the SR-3000 Provided by Australia
D Distance Histograms SR-2 and SR-3000
E Warmup Sequences SR-2 and SR-3000Numéro de notice : 15458 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse étrangère DOI : 10.3929/ethz-a-005465562 En ligne : http://dx.doi.org/10.3929/ethz-a-005465562 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=62724 Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 15458-01 35.11 Livre Centre de documentation En réserve M-103 Disponible
Titre : Modelling of spaceborne linear array sensors Type de document : Thèse/HDR Auteurs : Daniela Poli, Auteur Editeur : Zurich : Institut für Geodäsie und Photogrammetrie IGP - ETH Année de publication : 2005 Collection : IGP Mitteilungen, ISSN 0252-9335 num. 85 Importance : 204 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-906467-50-4 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] auto-étalonnage
[Termes IGN] C (langage)
[Termes IGN] capteur aérien
[Termes IGN] capteur en peigne
[Termes IGN] capteur spatial
[Termes IGN] chambre DTC
[Termes IGN] compensation par faisceaux
[Termes IGN] géométrie de l'image
[Termes IGN] géoréférencement direct
[Termes IGN] géoréférencement indirect
[Termes IGN] GPS-INS
[Termes IGN] image EROS
[Termes IGN] image MOMS-2P
[Termes IGN] image SPOT-HRS
[Termes IGN] image Terra-ASTER
[Termes IGN] image Terra-MISR
[Termes IGN] modèle géométrique de prise de vue
[Termes IGN] modèle mathématique
[Termes IGN] modèle par fonctions rationnelles
[Termes IGN] modèle stéréoscopique
[Termes IGN] orientation du capteur
[Termes IGN] orientation externe
[Termes IGN] orientation interne
[Termes IGN] point d'appui
[Termes IGN] point de vérification
[Termes IGN] points homologuesIndex. décimale : 35.11 Géométrie et qualité des prises de vues Résumé : (Auteur) The topic of this research is the development of a mathematical model for the georeferencing of imagery acquired by multi-line CCD array sensors, carried on air- or spacecraft. Linear array sensors are digital optical cameras widely used for the acquisition of panchromatic and multispectral images in pushbroom mode with spatial resolution ranging from few centimeters (airborne sensors) up to hundreds meters (spaceborne sensors). The images have very high potentials for photogrammetric mapping at different scales and for remote sensing applications. For example, they can be used for the generation of Digital Elevation Models (DEM), that represent an important basis for the creation of Geographic Information Systems, and the production of 3D texture models for visualization and animation purposes.
In the classical photogrammetric chain that starts from the radiometric preprocessing of the raw images and goes to the generation of products like the DEMs, the orientation of the images is a fundamental step and its accuracy is a crucial issue during the evaluation of the entire system. For pushbroom sensors, the triangulation and photogrammetric point determination are rather different compared to the standard approaches for full frame imagery and require special investigations on the sensor geometry and the acquisition mode.
Today various models based on different approaches have been developed, but few of them are rigorous and can be used for a wide class of pushbroom sensors. In general a rigorous sensor model aims to describe the relationship between image and ground coordinates, according to the physical properties of the image acquisition. The functional model is based on the collinearity equations. The sensor model presented in this thesis had to fulfil the requirement of being rigorous and at the same time as flexible as possible and adaptable to a wide class of linear array sensors. In fact pushbroom scanners in use show different geometric characteristics (optical systems, number of CCD lines, scanning mode, stereoscopy) and for each data set specific information are available (ephemeris, GPS/INS observations, calibration, other internal parameters). Therefore the model needs to be dependent on a certain number of parameters that may change for each sensor.
According to the availability of information on the sensor internal and external orientation, the proposed model includes two different orientation approaches.
The first one, the direct georeferencing one, is based on the estimations of the ground coordinates of the points measured in the images through a forward intersection, using the external orientation provided by GPS and INS instruments or interpolated by ephemeris or computed using the orbital parameters (satellite case). This approach does not require any ground control points, except for final checking, and does not estimate any additional parameters for the correction of the interior and exterior orientation. For this reason, the accuracy of this method depends on the accuracy of the external and internal orientation data.
The alternative orientation method, based on indirect georeferencing, is used if the sensor external and internal orientation is not available or not enough accurate for high-precision photograrnmetric mapping. This approach is a self-calibrating bundle adjustment. The sensor position and attitude are modelled with 2nd order piecewise polynomial functions (PPM) depending on time. Constraints on the segment borders assure the continuity of the functions, together with their first and second derivatives. Using pseudo-observations on the PPM parameters, the polynomial degree can be reduced to one (linear functions) or even to zero (constant functions). If GPS and INS are available, they are integrated in the PPM. For the self-calibration, additional parameters (APs) are used to model the lens internal parameters and distortions and the linear arrays displacements in the focal plane.
The parameters modelling the internal and external orientation, together with the ground coordinates of tie and control points, are estimated through a least-squares bundle adjustment using well distributed ground control points. The use of pseudo-observations allows the user to run the adjustment fixing any unknown parameters to certain values. This option is very useful not only for the external orientation modelling, but also for the analysis of the single self-calibration parameter's influence. The weights for the observations and pseudo-observations are determined according to the measurement accuracy. A blunder detection procedure is integrated for the automatic detection of wrong image coordinate measurement. The adjustment results are analyzed in terms of internal and external accuracy. The APs to be estimated are chosen according to their correlations with the other unknown parameters (ground coordinates of tie points and PPM parameters). A software has been developed under Unix environment in C language.
The flexibility of the model has been proved by testing it on MOMS-2P, SPOT-5/HRS, ASTER, MISR and EROS-A1 stereo images. These sensors have different characteristics (single-lens and multi-lens optical systems, various number of linear arrays, synchronous and asynchronous acquisition modes), covering a wide range of possible acquisition geometries.
For each dataset both the direct and indirect models have been used and in all cases the direct georeferencing was not accurate enough for high accurate mapping. The indirect model has been applied with different ground control points distributions (when possible), varying the PPM configurations (number of segments, polynomials degree) and with and without self-calibration. Excluding EROS-A1, all the imagery has been oriented with sub-pixels accuracy in the check points using a minimum of 6 ground control points. In case of EROS-A1, an accuracy in the range of I to 2 pixels has been achieved, due the lack of information on the geometry of the sensor asynchronous acquisition. For the ASTER and SPOT-5/HRS datasets, a DEM has also been generated and compared to some reference DEMs.
New cameras can be easily integrated in the model, because the required sensor information are accessible in literature as well as in the web. If no information on the sensor internal orientation is available, the model supposes that the CCD lines are parallel to each other in the focal plane and perpendicular to the flight direction and estimates any systematic error through the self-calibration. The satellite's position and velocity vectors, usually contained in the ephemeris, are required in order to compute the initial approximations for the PPM parameters. If this information is not available, the Keplerian elements can be used to estimate the nominal trajectory. For pushbroom scanners carried on airplane or helicopter the GPS and INS measurements are indispensable, due to the un-predictability of the trajectory.Note de contenu : 1. INTRODUCTION
1.1. REVIEW OF EXISTING MODELS
1.2. RESEARCH OBJECTIVES
1.3. OUTLINE
2. LINEAR CCD ARRAY SENSORS
2.1. SOLIDSTATE TECHNOLOGY
2.2. ARRAY GEOMETRIES
2.2. 1. Linear arrays
2.2.2. Other geometries
2.3. IMAGING SYSTEM
2.4. SENSOR CALIBRATION
2.4.1. Errors in CCD lines
2.4.2. Lens distortions
2.4.3. Laboratory calibration
2.5. STEREO ACQUISITION
2.5.1. Acrosstrack
2.5.2. Alongtrack
2.6. PLATFORMS
2.6.1. Satellite platforms
2.6.2. Airborne and helicopter platforms
2.7. IMAGE CHARACTERISTICS
2.7.1. Spatial resolution
2.7.2. Radiometric resolution
2.7.3. Spectral resolution
2.7.4. Temporal resolution
2.8. PROCESSING LEVELS
2.9. LIST OF LINEAR ARRAY SENSORS
2.10. CONCLUSIONS
3. DIRECT GEOREFERENCING
3.1. EXTERNAL ORIENTATION FROM GPS/INS
3.1.1. Background
3.1.2. GPS system
3.1.3. INS system
3.1.4. GPS/INS integration
3.1.5. Commercial systems
3.2. EXTERNAL ORIENTATION FROM EPHEMERIS
3.2.1. Orientation with Keplerian elements
3.2.2. Orientation from state vectors
3.2.3. Interpolation between reference lines
3.3. DIRECT GEOREFERENCING
3.3.1. From image to camera coordinates
3.3.2. From camera to ground coordinates
3.3.3. Estimation of approximate ground coordinates
3.3.4. Refinement
3.4. SOME CONSIDERATIONS ON GPS/INS MEASUREMENTS
3.5. ACCURACY EVALUATION
3.6. CONCLUSIONS
4. INDIRECT GEOREFERENCING
4.1. ALGORITHM OVERVIEW
4.2. EXTENTION TO MULTILENS SENSORS
4.3. EXTERNAL ORIENTATION MODELLING
4.3.1. Integration of GPS/INS observations
4.3.2. Function continuity
4.3.3. Reduction of polynomial order
4.4.SELFCALIBRATION
4.5. OBSERVATION EQUATIONS
4.5.1. Image coordinates
4.5.2. External orientation parameters
4.5.3. Selfcalibration parameters
4.5.4. Ground control points
4.6. LEAST SQUARES ADJUSTMENT
4.6.1. Theory of least squares adjustment
4.6.2. Linearization
4.6.3. Design matrix construction
4.6.4. Solution of linear system
4.7. ANALYSIS OF RESULTS
4.7.1. Internal accuracy
4.7.2. RMSE calculations
4.7.3. Correlations
4.7.4. Blunder detection
4.8. FORWARD INTERSECTION
4.9. SUMMARY AND COMMENTS
5. PREPROCESSING
5.1. METADATA FILES FORMATS
5.2. INFORMATION EXTRACTION FROM METADATA FILES
5.3. RADIOMETRIC PREPROCESSING
5.3.1. Standard algorithms
5.3.2. Adhoc filters
6. APPLICATIONS
6.1. WORKFLOW
6.2. MOMS02
6.2.1. Sensor description
6.2.2. Data description
6.2.3. Preprocessing
6.2.4. Image orientation
6.2.5. Summary and conclusions
6.3. SPOT5/HRS
6.3.1. Sensor description
6.3.2. Data description
6.3.3. Preprocessing
6.3.4. Image orientation
6.3.5. DEM generation
6.3.6. Comparison
6.3.7. Summary and conclusions
6.4 ASTER
6.4.1. Sensor description
6.4.2. Data description
6.4.3. Preprocessing
6.4.4. Images orientation
6.4.5. DEM generation
6.4.6. Comparison with reference DEMs
6.4.7. Summary and conclusions
6.5 MISR
6.5.1. Sensor description
6.5.2. Data description
6.5.3. Preprocessing
6.5.4. Image orientation
6.5.5. Summary and conclusions
6.6 EROS-A1
6.6.1. Sensor description
6.6.2. Data description and Preprocessing
6.6.3. Image orientation
6.6.4. Summary and conclusions
7. CONCLUSION AND OUTLOOK
7.1 CONCLUSION
7.2 OUTLOOKNuméro de notice : 13260 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse étrangère DOI : 10.3929/ethz-a-004946341 En ligne : http://dx.doi.org/10.3929/ethz-a-004946341 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54943 Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 13260-01 35.11 Livre Centre de documentation En réserve M-103 Disponible
Titre : Ein hybrides Meßsystem zur Kalibrierung von Strichteilungen Titre original : [Un système de mesure hybride pour l'étalonnage de division de traits] Type de document : Thèse/HDR Auteurs : O. Freide, Auteur Mention d'édition : 1 Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2000 Collection : DGK - C Sous-collection : Dissertationen num. 521 Importance : 70 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-9560-1 Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] chambre DTC
[Termes IGN] détection de contours
[Termes IGN] erreur systématique
[Termes IGN] étalonnage d'instrument
[Termes IGN] étalonnage de capteur (imagerie)
[Termes IGN] filtrage du bruit
[Termes IGN] filtre de Canny
[Termes IGN] filtre de Deriche
[Termes IGN] interféromètre au laser
[Termes IGN] pixel
[Termes IGN] précision millimétriqueIndex. décimale : 35.11 Géométrie et qualité des prises de vues Résumé : (Auteur) This thesis presents a new system for the calibration of scales of random code and length. For this purpose, a laser interferometer and a CCD-array camera are combined to form a hybrid measuring system with an accuracy better than ±5 µm. Laserbeam and longitudinal axis of the scale are arranged colinearly. The camera is positioned perpendicular to this axis and observes a 1 cm2 large window of the scale. As the distance between the two edges of a line of a bar code scale may be wider than the size of the window, they are observed separately one after the other. The center of a line, used by definition for the calibration, can be derived from the two images. Measurement is possible under both static and dynamic conditions. The difference is that, as both gauges are read out simultaneously, the scale stands still or moves in longitudinal direction. For static measurements, the edge positions are approximately adjusted by means of their nominal value, which automatically reduces the number of observations to a minimum. Of course, dynamic measurement is faster, but the technical demands are higher due to the steady read out of both gauges. In order to reduce the amount of data, only those images with at least one visible edge of the bar code are stored. Therefore, after grabbing, each image is immediately scanned for edges by a simple but imprecise method. The precise determination of the distance between the edge and the origin of the image coordinate system is done off-line after the measurement, using their entire width in the radiometrically corrected image. The distance between the edge and the origin of the coordinate system is transformed by a previously determined scale factor into the metric system of the laser. After meteorological correction, the laser value determines the shift relative to the arbitrarily chosen start position yielding the geometric relation between the images. After describing the physical principles and their technical realisation, the errors of both sensors are presented in a systematic manner to give an estimate of the accuracy of the system. Especially for the camera, practical research results concerning lens distortion, system noise, sensor sensitivity, and lighting effects are presented. To extract the edges in an image reliably and with sub-pixel accuracy, different algorithms for edge detection are explained in detail and compared with regard to their performance. This includes the Difference-of-Boxes, Laplacian-of-Gaussian, Difference-of-Gaussians and the shen, canny, deriche filter group. With these algorithms, sub-pixel accuracy can already be achieved by the proposed evaluation stra-tegy in the twodimensional image. Special sub-pixel precise algorithms are only summarized because they merely reduce noise as demonstrated by the “STEGER-Filter”. Finally, the results of the practical application of the measurement system with respect to the calibration of Invar-Barcode staffs are presented. Numéro de notice : 27822 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=56446 Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 27822-01 35.11 Livre Centre de documentation En réserve M-103 Disponible
Titre : Géométrie des images : cycle A et B de l'ENSG, année 1987-1988 Type de document : Guide/Manuel Auteurs : Alain Baudoin Editeur : Paris : Institut Géographique National - IGN (1940-2007) Année de publication : 1988 Importance : 74 p. Format : 21 x 30 cm Langues : Français (fre) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] balayage laser
[Termes IGN] capteur à balayage
[Termes IGN] chambre de prise de vues argentique
[Termes IGN] correction géométrique
[Termes IGN] corrélation automatique de points homologues
[Termes IGN] courbe épipolaire
[Termes IGN] déformation d'image
[Termes IGN] géométrie de l'image
[Termes IGN] image satellite
[Termes IGN] modélisation géométrique de prise de vue
[Termes IGN] orbite
[Termes IGN] prise de vue radiométrique
[Termes IGN] radiomètre à balayage
[Termes IGN] restitution automatique
[Termes IGN] satellite artificiel
[Termes IGN] système spatialIndex. décimale : 35.11 Géométrie et qualité des prises de vues Numéro de notice : 58228 Affiliation des auteurs : IGN (1940-2011) Thématique : IMAGERIE Nature : Manuel de cours IGN Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=48477 Exemplaires(3)
Code-barres Cote Support Localisation Section Disponibilité 58228-01 35.11 Livre Centre de documentation En réserve M-103 Disponible 58228-03 35.11 Livre Centre de documentation En réserve M-103 Disponible 58228-02 35.11 Livre Centre de documentation En réserve M-103 Disponible PermalinkPermalinkContrôle de la distorsion géométrique dans tout le champ d'un objectif de prise de vues aériennes / Daniel Preux (1976)
PermalinkPermalinkPermalinkPermalinkPermalinkPermalinkPermalink
