National Repository of Grey Literature 6 records found  Search took 0.00 seconds. 
Measurement and Evaluation of Axis Straightness of Rotary Forgings using Photogrammetry and Image Analysis
Zatočilová, Aneta ; Druckmüller, Miloslav (referee) ; Matula, Pavel (referee) ; Morovič,, Ladislav (referee) ; Brandejs, Jan (advisor)
The thesis deals with methodology proposal for shape and dimension measurement of rotationally symmetric forgings. Most of available non-contact systems are not possible to use for this purpose, mainly due to high temperatures and large dimensions of forgings. Only a few commercial systems which are designed for this specific measurement are currently in the market. These systems are based on a principle of evaluating time response of posted modulated signal. However, scientific literature shows also other approaches to the measurement, which are based on principle of triangulation and methods of image analysis. Advantage of systems based on these principles should be especially measurement speed and significantly lower price. The paper describes current state of research and development in this area and proposes a new approach which is based on passive photogrammetry and image analysis. The core of the work is devoted to the design of partial methods and their implementation in the Matlab programming language. Functionality of the methodology and the software has been verified by measuring cylindrical tubes of small dimensions in laboratory conditions. The designed methods were discussed and evaluated based on statistical analysis of the measurement results, and further steps to increase the accuracy and reduce the spread of results were suggested. Optimization and further development of this methodology could lead to the design a professional measuring system intended for this specific application.
Automatic Generation of Scanning Positions for Sheet Metal Parts Digitization
Koutecký, Tomáš ; Druckmüller, Miloslav (referee) ; Matula, Pavel (referee) ; Morovič,, Ladislav (referee) ; Brandejs, Jan (advisor)
This thesis deals with the development of a new methodology for automatic generation of scanning positions based on a computer model of the part for digitization of sheet metal parts. Manufacture and related inspection of sheet metal parts are closely connected to automotive industry. Based on increasing general requirements on accuracy, there is also a requirement for accurate inspection of manufactured parts in serial-line production. Optical 3D scanners and industrial robots are used more often for that purpose. Measuring positions for accurate and fast digitization of a part need to be prepared as the manufacturing of the new part begins. Planning of such positions is done manually by positioning of the industrial robot and saving the positions. The planning of positions proposed by this methodology is done automatically. A methodology of positions planning, their simulation for true visibility of the part elements using reflectance model and a simulation of the positions for robot reachability is presented in this thesis. The entire methodology is implemented as a plug-in for the Rhinoceros software. High reduction of time in positions planning compared to the manual approach was observed in the performed experiments.
Digital Image Processing of Cross-section Samples
Beneš, Miroslav ; Zitová, Barbara (advisor) ; Matula, Pavel (referee) ; Pelagotti, Anna (referee)
The thesis is aimed on the digital analysis and processing of micro- scopic image data with a focus on cross-section samples from the artworks which fall into cultural heritage domain. It contributes to solution of two different problems of image processing - image seg- mentation and image retrieval. The performance evaluation of differ- ent image segmentation methods on a data set of cross-section images is carried out in order to study the behavior of individual approaches and to propose guidelines how to choose suitable method for segmen- tation of microscopic images. Moreover, the benefit of segmenta- tion combination approach is studied and several distinct combination schemes are proposed. The evaluation is backed up by a large number of experiments where image segmentation algorithms are assessed by several segmentation quality measures. Applicability of achieved re- sults is shown on image data of different origin. In the second part, content-based image retrieval of cross-section samples is addressed and functional solution is presented. Its implementation is included in Nephele system, an expert system for processing and archiving the material research reports with image processing features, designed and implemented for the cultural heritage application area. 1
Digital Image Processing of Cross-section Samples
Beneš, Miroslav ; Zitová, Barbara (advisor) ; Matula, Pavel (referee) ; Pelagotti, Anna (referee)
The thesis is aimed on the digital analysis and processing of micro- scopic image data with a focus on cross-section samples from the artworks which fall into cultural heritage domain. It contributes to solution of two different problems of image processing - image seg- mentation and image retrieval. The performance evaluation of differ- ent image segmentation methods on a data set of cross-section images is carried out in order to study the behavior of individual approaches and to propose guidelines how to choose suitable method for segmen- tation of microscopic images. Moreover, the benefit of segmenta- tion combination approach is studied and several distinct combination schemes are proposed. The evaluation is backed up by a large number of experiments where image segmentation algorithms are assessed by several segmentation quality measures. Applicability of achieved re- sults is shown on image data of different origin. In the second part, content-based image retrieval of cross-section samples is addressed and functional solution is presented. Its implementation is included in Nephele system, an expert system for processing and archiving the material research reports with image processing features, designed and implemented for the cultural heritage application area. 1
Measurement and Evaluation of Axis Straightness of Rotary Forgings using Photogrammetry and Image Analysis
Zatočilová, Aneta ; Druckmüller, Miloslav (referee) ; Matula, Pavel (referee) ; Morovič,, Ladislav (referee) ; Brandejs, Jan (advisor)
The thesis deals with methodology proposal for shape and dimension measurement of rotationally symmetric forgings. Most of available non-contact systems are not possible to use for this purpose, mainly due to high temperatures and large dimensions of forgings. Only a few commercial systems which are designed for this specific measurement are currently in the market. These systems are based on a principle of evaluating time response of posted modulated signal. However, scientific literature shows also other approaches to the measurement, which are based on principle of triangulation and methods of image analysis. Advantage of systems based on these principles should be especially measurement speed and significantly lower price. The paper describes current state of research and development in this area and proposes a new approach which is based on passive photogrammetry and image analysis. The core of the work is devoted to the design of partial methods and their implementation in the Matlab programming language. Functionality of the methodology and the software has been verified by measuring cylindrical tubes of small dimensions in laboratory conditions. The designed methods were discussed and evaluated based on statistical analysis of the measurement results, and further steps to increase the accuracy and reduce the spread of results were suggested. Optimization and further development of this methodology could lead to the design a professional measuring system intended for this specific application.
Automatic Generation of Scanning Positions for Sheet Metal Parts Digitization
Koutecký, Tomáš ; Druckmüller, Miloslav (referee) ; Matula, Pavel (referee) ; Morovič,, Ladislav (referee) ; Brandejs, Jan (advisor)
This thesis deals with the development of a new methodology for automatic generation of scanning positions based on a computer model of the part for digitization of sheet metal parts. Manufacture and related inspection of sheet metal parts are closely connected to automotive industry. Based on increasing general requirements on accuracy, there is also a requirement for accurate inspection of manufactured parts in serial-line production. Optical 3D scanners and industrial robots are used more often for that purpose. Measuring positions for accurate and fast digitization of a part need to be prepared as the manufacturing of the new part begins. Planning of such positions is done manually by positioning of the industrial robot and saving the positions. The planning of positions proposed by this methodology is done automatically. A methodology of positions planning, their simulation for true visibility of the part elements using reflectance model and a simulation of the positions for robot reachability is presented in this thesis. The entire methodology is implemented as a plug-in for the Rhinoceros software. High reduction of time in positions planning compared to the manual approach was observed in the performed experiments.

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