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[Truncated abstract] The development of an automated classification system of wear particles or surfaces is of great interest to the machine condition monitoring industry. The system, once developed, may also find applications in medical diagnostics. Such a tool will be able to replace human experts in the detection of the onset of early machine failure, or in the diagnosis and prognosis of, for example, joint diseases. This will improve efficiency, reliability and also reduce costs of monitoring or diagnostic systems. Current literature available on this topic has included various studies on different classification methods. However, there has been no work conducted on the development of a totally integrated automated classification system. The first part of this thesis presents a study investigating the efficiency and robustness of various pattern recognition methods currently described in literature. A special computer program was developed to test each of the classification methods against both standard image databases and tribological surface images. There are three core components of a pattern recognition system that need to be analysed: (1) feature extraction, (2) feature reduction and (3) classifier. Each of these components provides a vital link that can affect the reliability of the complete classification system. ... The optimal classifier was the Linear Support Vector Classifier. This part of research is described in Paper 2. The second part of this thesis contains work verifying the performance of the automated classification system developed using both tribological and bio-tribological surface images. Experiments were carried out to generate wear particles created under different wear mechanisms (adhesive, abrasive and fatigue wear) and various operating conditions representing different degree of wear severity. The automated classification system developed was able to successfully classify wear particles with respect to both the type of wear mechanism operating and the wear severity. The results of this classification are described in Papers 3 and 5. The success of the automated classification system was also confirmed by its ability to classify different groups of worn (osteoarthritic) cartilage surfaces (Paper 4). This could lead to potential applications of the system for early detection of the onset of osteoarthritis. In conclusion, the automated classification system developed can accurately classify both tribological and bio-tribological surface images. This system could become a vitally important tool in both machine condition monitoring and medical diagnostics.

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Orientador: Nivaldo Lemos Coppini / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-07-23T13:30:45Z (GMT). No. of bitstreams: 1 ArenasMiranda_GilbertoWalter_M.pdf: 6822675 bytes, checksum: a20677c1c3d03b638ab12a7cb98399f5 (MD5) Previous issue date: 1997 / Resumo: Este trabalho trata da proposta de metodologia que, tomando como base a vida da aresta de corte em termos de número de peças usinadas ou comprimento de corte, permite através da utilização de um sistema especialista a otimização de processo de usinagem, além de propiciar a determinação do melhor momento para a troca da aresta de corte. O sistema de monitoramento empregado utilizando sensores de força/potência de corte pode cumprir funções para tomada de decisões ou simplesmente de segurança. O número de peças ou comprimento de corte foram os critérios adotados para definir o momento de troca da aresta de corte. O trabalho permite concluir que a metodologia é adequada para ser utilizada em Controle Adaptativo Otimizado / Abstract: This work presents a proposed methodology to be applied for Optimized Adaptive Control. The methodology validity was done experimentally. The methodology based on the cutting edge toollife helps the user to find the optimized cutting speed with the aid of an expert system . Force and power sensors were used, first to help the user to determine the best moment to change the cutting edge and second as a safety system. The experiences carried out in the work allow to conclude that the proposed methodology is very adequate to be used for Optimized Adaptive Control / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica

Thesis (Nav. E.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004. / Includes bibliographical references (p. 89-90). / The Non-Intrusive Load Monitor (NILM) provides a method of measuring component performance and source power quality through a single point of entry in the power distribution system. A study was performed utilizing the NILM onboard three different ships (along with experimentation in the laboratory) to determine its effectiveness in determining the state of mechanical systems through analysis of electrical power data. Data collected from the Auxiliary Seawater System onboard the USCGC SENECA indicate that the NILM is able to predict several faults (clogged pump inlet strainers, faulty motor/pump coupling, fouled heat exchangers) as well as provide a backup indication of flow levels to heat loads. Data collected from the Sewage System of the SENECA indicate several metrics which can be applied to cycling systems in general to differentiate between periods of heavy usage and fault conditions. Finally, data collected from the Steering System of the SENECA as well as a yard patrol boat operated by the Office of Naval Research shows the potential of the NILM to be used as a control system without the need for separate mechanical transducers. / by Jack S. Ramsey, Jr. / S.M. / Nav.E.

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Orientador: Anselmo Eduardo Diniz / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-07-23T21:54:22Z (GMT). No. of bitstreams: 1 Matsumoto_Hidekasu_D.pdf: 9333077 bytes, checksum: 51f227c51103bc62610f0c64d486742b (MD5) Previous issue date: 1998 / Resumo: Neste trabalho procurou-se estudar a viabilidade de se tornear aços no estado endurecido utilizando máquinas de projeto mecânico convencional (sem mancais hidrostáticos e com um certo desgaste) comandadas numericamente, com a finalidade substituir as operações de retificação. Para tanto, usinou-se dois tipos de corpos de prova, de aço ABNT 52100 temperado e revenido com dureza média de 60 HRc (Rockwell C), com ferramentas de corte de PCBN (65% de CBN) e cerâmica mista ('Al IND. 2¿ 'O IND. 3¿ + TiC) encontradas no mercado. Monitorou-se os ensaios via corrente do motor principal e emissão acústica, com a finalidade de determinar o momento da substituição da ferramenta de corte. Após a análise dos resultados, chegou-se às seguintes conclusões: a) é possível substituir as operações de retificação por torneamento com máquina de projeto mecânico convencional, uma vez que se obteve qualidade IT5 e rugosidade menor que Ra = 0,6 'mu¿m, com vidas das ferramentas suficientemente longas para determinadas aplicações; b) os métodos de análise dos sinais de emissão acústica e corrente do motor utilizados, não se mostraram adequados para indicar o momento da troca da ferramenta; c) em geral, a ferramenta cerâmica apresentou vida média maior que a ferramenta de PCBN, porém com uma dispersão também maior / Abstract: The main goal of this work is to study the feasibility of turning hardened steels using a lathe with a conventional mechanical design (without hydrostatic bearings), aiming to replace grinding operations. For this purpose, two kinds of quenched and tempered 52100 steel workpieces were machined, with average hardness of 60 HRc, using PCBN (65% of CBN) and mixed ceramic ('Al IND 2¿¿O IND. 3¿ + TiC) tools. Both the electrical current of the main motor and the acoustic emission were monitored, aiming to automatically establish the moment to replace the tool. After the result analyses, the following conclusions were drawn: a) it is possible to replace grinding operations by turning with a conventional mechanical design lathe, since the workpiece quality obtained was within IT5 and the surface roughness was below Ra = 0.6 ' 'mu¿m, with tool life long enough for this kind of applications; b) the tool life monitoring through acoustic emission and electrical current of the main motor did not show to be suitable to establish the moment to replace the tool; c) in general, mixed ceramic tool had longer average toollife than PCBN tool, but presented larger scatter / Doutorado / Materiais e Processos de Fabricação / Doutor em Engenharia Mecânica

This thesis discusses the design considerations for a machine conditioning sensor utilizing Bluetooth low energy (BLE).

Analysis of rotating machinery requires the collection and evaluation of large quantities of data. For just one machine, the amount of data may become so overwhelmingly great that a thorough examination of all the data is rendered impractical. <b>IMTS</b> (Intelligent Monitoring And Trending System) is a data acquisition system that has been developed to help resolve this problem. <b>IMTS</b> is a pc based system which can collect data that is relevant to diagnostic considerations, perform an evaluation by filtering the data through special standards and store the results for later review. The system is flexible because the data is evaluated by user defined, multi-level references called standards. <b>IMTS</b> operates in the Microsoft Windows 3.0 operating system, which has the advantage of multitasking two or more programs and thereby allows the data to be collected, evaluated and displayed simultaneously. This means that the user does not experience any temporary periods of system inaccessibility as would be the case in a sequential operating system, such as DOS. This thesis discusses the development of <b>IMTS</b> and explains the capabilities of the current system configuration and gives examples of the monitor screen options and trend plotting capabilities. / Master of Science