A machine vision-based approach to measuring the size distribution of rocks on a conveyor belt

dc.contributor.advisorde Jager, Gerhard
dc.contributor.authorMkwelo, Simphiwe
dc.date.accessioned2024-07-02T09:52:17Z
dc.date.available2024-07-02T09:52:17Z
dc.date.issued2004
dc.date.updated2024-06-25T13:49:33Z
dc.description.abstractThis work involves the development of a vision-based system for measuring the size distribution of rocks on a conveyor belt. The system has applications in automatic control and optimization of milling machines, and the selection of optimal blasting methods in the mining industry. Rock size is initially assumed to be the projected rock surface area due to the constraint imposed by the 2D nature of images. This measurement is facilitated by locating connected rock-edge pixels. Rock edge detection is achieved using a watershed-based segmentation process. This process involves image pre-filtering with edge preserving filters at various degrees of filtering. The output of each filtering stage is retained and marker-driven watersheds are applied on each output resulting to traces of detected rock boundaries. Watershed boundary selection is then applied to select boundaries which are most likely to be rock edges based on rock features. Finally, rock recognition using feature classification is applied to remove non-rock watershed boundaries. The projected rock area distribution of a test-set is measured and compared to corresponding projected areas of manually segmented images. The obtained distributions are found to be similar with an RMS error of 2.37% on the test-set. Finally, sieve data is collected in the form of actual rock size distributions and a quantitative comparison between the actual and machine measured distributions is performed. The overall quantitative result is that the two rock size distributions are significantly different. However, after incorporating a stereology-based correction, hypothesis tests on a 3m belt-cut test-set show that the obtained distributions are similar.
dc.identifier.apacitationMkwelo, S. (2004). <i>A machine vision-based approach to measuring the size distribution of rocks on a conveyor belt</i>. (). University of Cape Town ,Faculty of Engineering and the Built Environment ,Department of Electrical Engineering. Retrieved from http://hdl.handle.net/11427/40138en_ZA
dc.identifier.chicagocitationMkwelo, Simphiwe. <i>"A machine vision-based approach to measuring the size distribution of rocks on a conveyor belt."</i> ., University of Cape Town ,Faculty of Engineering and the Built Environment ,Department of Electrical Engineering, 2004. http://hdl.handle.net/11427/40138en_ZA
dc.identifier.citationMkwelo, S. 2004. A machine vision-based approach to measuring the size distribution of rocks on a conveyor belt. . University of Cape Town ,Faculty of Engineering and the Built Environment ,Department of Electrical Engineering. http://hdl.handle.net/11427/40138en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Mkwelo, Simphiwe AB - This work involves the development of a vision-based system for measuring the size distribution of rocks on a conveyor belt. The system has applications in automatic control and optimization of milling machines, and the selection of optimal blasting methods in the mining industry. Rock size is initially assumed to be the projected rock surface area due to the constraint imposed by the 2D nature of images. This measurement is facilitated by locating connected rock-edge pixels. Rock edge detection is achieved using a watershed-based segmentation process. This process involves image pre-filtering with edge preserving filters at various degrees of filtering. The output of each filtering stage is retained and marker-driven watersheds are applied on each output resulting to traces of detected rock boundaries. Watershed boundary selection is then applied to select boundaries which are most likely to be rock edges based on rock features. Finally, rock recognition using feature classification is applied to remove non-rock watershed boundaries. The projected rock area distribution of a test-set is measured and compared to corresponding projected areas of manually segmented images. The obtained distributions are found to be similar with an RMS error of 2.37% on the test-set. Finally, sieve data is collected in the form of actual rock size distributions and a quantitative comparison between the actual and machine measured distributions is performed. The overall quantitative result is that the two rock size distributions are significantly different. However, after incorporating a stereology-based correction, hypothesis tests on a 3m belt-cut test-set show that the obtained distributions are similar. DA - 2004 DB - OpenUCT DP - University of Cape Town KW - Electrical Engineering LK - https://open.uct.ac.za PY - 2004 T1 - ETD: A machine vision-based approach to measuring the size distribution of rocks on a conveyor belt TI - ETD: A machine vision-based approach to measuring the size distribution of rocks on a conveyor belt UR - http://hdl.handle.net/11427/40138 ER - en_ZA
dc.identifier.urihttp://hdl.handle.net/11427/40138
dc.identifier.vancouvercitationMkwelo S. A machine vision-based approach to measuring the size distribution of rocks on a conveyor belt. []. University of Cape Town ,Faculty of Engineering and the Built Environment ,Department of Electrical Engineering, 2004 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/40138en_ZA
dc.language.rfc3066eng
dc.publisher.departmentDepartment of Electrical Engineering
dc.publisher.facultyFaculty of Engineering and the Built Environment
dc.publisher.institutionUniversity of Cape Town
dc.subjectElectrical Engineering
dc.titleA machine vision-based approach to measuring the size distribution of rocks on a conveyor belt
dc.typeThesis / Dissertation
dc.type.qualificationlevelMasters
dc.type.qualificationlevelMSc
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