Prof. Hans-Gerd Maas Profile

Prof. Hans-Gerd Maas

at TU Dresden

SPIE Involvement:

Author

Publications (17)

Proceedings Article | 1 October 2011 Paper

Wide field-of-view all-reflective objectives designed for multispectral image acquisition in photogrammetric applications

Kristof Seidl, Katja Richter, Jens Knobbe, Hans-Gerd Maas

Proceedings Volume 8172, 817210 (2011) https://doi.org/10.1117/12.896754

KEYWORDS: Objectives, Cameras, Unmanned aerial vehicles, Mirrors, Imaging systems, Distortion, Calibration, Image sensors, Chromatic aberrations, Multispectral imaging

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Proceedings Article | 21 June 2011 Paper

Integration of photogrammetry and acoustic emission analysis for assessing concrete structures during loading tests

R. Koschitzki, G. Schacht, D. Schneider, S. Marx, H.-G. Maas

Proceedings Volume 8085, 80850I (2011) https://doi.org/10.1117/12.889558

KEYWORDS: Acoustic emission, Failure analysis, Analytical research, Sensors, Cameras, Image analysis, Photogrammetry, Transducers, Visualization, Signal processing

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Proceedings Article | 29 January 2007 Paper

Concepts of single highspeed-camera photogrammetric 3D measurement systems

Hans-Gerd Maas

Proceedings Volume 6491, 64910K (2007) https://doi.org/10.1117/12.703795

KEYWORDS: Cameras, Imaging systems, Mirrors, Projection systems, 3D metrology, Calibration, 3D modeling, Sensors, Systems modeling, Motion analysis

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Highspeed cameras form a central component of photogrammetric 3D measurement systems in applications requiring a high temporal resolution in fields such as fast object tracking or high frequency deformation measurement. Current highspeed cameras offer data rates in the order of 1 Gigabyte per second or beyond, delivering for instance 1000 frames per second at 1000×1000 pixels. Most applications using highspeed cameras for visualization or measurement purposes are still 2D. Highspeed camera stereo systems are rare because of the costs of cameras and the lack of synchronizibility of some camera types. The paper gives a short overview on single camera 3D measurement system concepts. It presents two concepts of setting up photogrammetric 3D measurement systems based on a single highspeed camera in detail, one based on a single camera with a stereo mirror system and one on based on a camera-projector combination: A stereo mirror system in front of a camera generates multiple views on one sensor. These views can be considered virtual cameras of a multi-camera photogrammetric measurement system. The paper presents a flexible quadruple-mirror system to be used in 3D motion analysis applications and discusses geometric modeling and system calibration. Photogrammetric surface measurement systems can be configured by a camera and a projector device projecting strip or dot patterns onto a surface. Using the projector as an active element in the system design, dense and accurate 3D surface representations may be generated using coded light approach or phase shift techniques. In the geometric modeling and calibration, the projector can be considered an inverse camera with infinite frame rate. The paper presents results of an accuracy test obtaining a precision potential in the order of ¹/₅₀ pixel from a standard consumergrade beamer. Besides the system design and the geometric modeling of the two concepts, the paper shows results from pilot studies and practical applications.

Proceedings Article | 29 January 2007 Paper

Configuration of multi mirror systems for single high-speed camera based 3D motion analysis

Torsten Putze, Karsten Raguse, Hans-Gerd Maas

Proceedings Volume 6491, 64910L (2007) https://doi.org/10.1117/12.700109

KEYWORDS: Cameras, Imaging systems, Mirrors, High speed cameras, Motion analysis, Particles, Beam splitters, Safety, Image analysis, Analytical research

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Proceedings Article | 10 January 2003 Paper

Optical triangulation method for height measurements on water surfaces

Hans-Gerd Maas, Bernd Hentschel, Frank Schreiber

Proceedings Volume 5013, (2003) https://doi.org/10.1117/12.473088

KEYWORDS: Water, Reflection, Cameras, Visualization, Image processing, 3D modeling, Laser optics, Image quality, Optical testing, Particles

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Proceedings Article | 14 December 1998 Paper

Suitability of digital camcorders for virtual reality image data capture

Nicola D'Apuzzo, Hans-Gerd Maas

Proceedings Volume 3641, (1998) https://doi.org/10.1117/12.333790

KEYWORDS: Cameras, Video, CCD cameras, Digital imaging, Virtual reality, Frame grabbers, Machine vision, RGB color model, Image acquisition, Photogrammetry

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Proceedings Article | 14 December 1998 Paper

Evaluation of image compression in 3D PTV

Heinrich Stueer, Jochen Willneff, Hans-Gerd Maas

Proceedings Volume 3641, (1998) https://doi.org/10.1117/12.333787

KEYWORDS: Image compression, Particles, Chromium, 3D image processing, Wavelets, Cameras, 3D metrology, Data storage, Image quality standards, Image processing

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Proceedings Article | 7 July 1997 Paper

Dynamic photogrammetric calibration of industrial robots

Hans-Gerd Maas

Proceedings Volume 3174, (1997) https://doi.org/10.1117/12.279771

KEYWORDS: Robots, Calibration, Computer programming, Data modeling, Kinematics, Tolerancing, Digital photography, Photogrammetry, Robotic systems, Reliability

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Today's developments in industrial robots focus on aims like gain of flexibility, improvement of the interaction between robots and reduction of down-times. A very important method to achieve these goals are off-line programming techniques. In contrast to conventional teach-in-robot programming techniques, where sequences of actions are defined step-by- step via remote control on the real object, off-line programming techniques design complete robot (inter-)action programs in a CAD/CAM environment. This poses high requirements to the geometric accuracy of a robot. While the repeatability of robot poses in the teach-in mode is often better than 0.1 mm, the absolute pose accuracy potential of industrial robots is usually much worse due to tolerances, eccentricities, elasticities, play, wear-out, load, temperature and insufficient knowledge of model parameters for the transformation from poses into robot axis angles. This fact necessitates robot calibration techniques, including the formulation of a robot model describing kinematics and dynamics of the robot, and a measurement technique to provide reference data. Digital photogrammetry as an accurate, economic technique with realtime potential offers itself for this purpose. The paper analyzes the requirements posed to a measurement technique by industrial robot calibration tasks. After an overview on measurement techniques used for robot calibration purposes in the past, a photogrammetric robot calibration system based on off-the- shelf lowcost hardware components will be shown and results of pilot studies will be discussed. Besides aspects of accuracy, reliability and self-calibration in a fully automatic dynamic photogrammetric system, realtime capabilities are discussed. In the pilot studies, standard deviations of 0.05 - 0.25 mm in the three coordinate directions could be achieved over a robot work range of 1.7 X 1.5 X 1.0 m³. The realtime capabilities of the technique allow to go beyond kinematic robot calibration and perform dynamic robot calibration as well as photogrammetric on-line control of a robot in action.

Proceedings Article | 7 July 1997 Paper

Accuracy potential of large-format still-video cameras

Hans-Gerd Maas, Markus Niederoest

Proceedings Volume 3174, (1997) https://doi.org/10.1117/12.279775

KEYWORDS: Cameras, CCD image sensors, Digital photography, Photogrammetry, Digital imaging, Imaging systems, Computing systems, Power supplies, Control systems, Data storage

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Proceedings Article | 13 September 1995 Paper

Kodak DCS200: a camera for high-accuracy measurements?

Armin Gruen, Hans-Gerd Maas, Andrea Keller

Proceedings Volume 2598, (1995) https://doi.org/10.1117/12.220923

KEYWORDS: Cameras, Sensors, Calibration, CCD cameras, CCD image sensors, 3D acquisition, Photogrammetry, Data conversion, Power supplies, Data storage

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SPIE Journal Paper | 1 July 1995

Digital photogrammetric techniques for high-resolution three-dimensional flow velocity measurements

Hans-Gerd Maas, Armin Gruen

OE, Vol. 34, Issue 07, (July 1995) https://doi.org/10.1117/12.10.1117/12.204687

KEYWORDS: Particles, 3D image processing, 3D acquisition, Visualization, Velocity measurements, Data acquisition, CCD cameras, Image processing, 3D metrology, Cameras

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Proceedings Article | 6 October 1994 Paper

High-speed camera system for the acquisition of flow tomography sequences for 3D least squares matching

Hans-Gerd Maas

Proceedings Volume 2350, (1994) https://doi.org/10.1117/12.189155

KEYWORDS: Tomography, 3D acquisition, Seaborgium, Imaging systems, Data acquisition, Cameras, Solid state cameras, Visualization, High speed cameras, Laser induced fluorescence

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Proceedings Article | 6 October 1994 Paper

Digital close-range photogrammetry for dimensional checking and control in a shipyard

Hans-Gerd Maas, Thomas Kersten

Proceedings Volume 2350, (1994) https://doi.org/10.1117/12.189124

KEYWORDS: Cameras, Digital photography, Photogrammetry, Data acquisition, Imaging systems, Data processing, Digital imaging, Image processing, Target detection, Calibration

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Proceedings Article | 17 August 1994 Paper

From pixels to voxels: tracking volume elements in sequences of 3D digital images

Hans-Gerd Maas, Anthony Stefanidis, Armin Gruen

Proceedings Volume 2357, (1994) https://doi.org/10.1117/12.182861

KEYWORDS: 3D image processing, Chemical elements, Image processing, Tomography, Solid state cameras, Visualization, Seaborgium, Photogrammetry, Image analysis, Imaging systems

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