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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Desenvolvimento de uma bancada didática para estudo dos efeitos termoelétricos aplicados na engenharia

Izidoro, Cleber Lourenço January 2015 (has links)
O presente trabalho apresenta o desenvolvimento de uma bancada didática de baixo custo para estudo dos materiais termoelétricos para a realização de ensaios de obtenção de curvas de desempenho dos módulos termoelétricos no que se refere a geração de energia pelo Efeito Seebeck e resfriamento através do Efeito Peltier de forma a difundir os conhecimentos nas áreas afim em escolas de Engenharia, refletindo na compreensão dos princípios e funcionalidades destas tecnologias. O sistema proposto permite ler simultaneamente até 3 geradores termoelétricos, e é composto por dois principais circuitos eletrônicos: sendo um estágio aquisição de dados compostos por 3 canais para leitura de tensão, 3 canais para corrente e 6 canais para aquisição do sinal dos termopares (<400°C) além de sistema térmico que terá as funções de aquecimento e resfriamento. Os dados medidos são adquiridos para um computador com um software customizado a aplicação que permite o monitoramento das grandezas envolvidas (tensão, corrente, potência e temperatura) para acompanhamento do ensaio dos materiais termoelétricos, tanto por meio de uma indicação numérica como gráfica. O sistema de aquisição de dados possui precisa o para temperatura de ±2,5%, para tensão de ±2,5% e para corrente de ±1,5%. / The present work describes the development of a low cost didactic bench for Study of thermoelectric materials for performing obtaining performance curves testing of thermoelectric modules in regard to energy generation effect Seebeck and cooling via Peltier Effect order to disseminate knowledge in areas related to engineering schools, reflecting the understanding of the principles and features of these technologies. The proposed system can be read simultaneously up to 3 thermoelectric generators, and consists of two main electronic circuits: being a stage data acquisition composed of 3 channels for reading voltage and 3 channels for current using ACS712 instrumentation amplifiers and 6 channels signal acquisition thermocouples (<400 ° C) as well as thermal system will have the heating and cooling functions. The measured data is acquired to a computer with software developed in Delphi language, which allows monitoring of the quantities involved (voltage, current, power and temperature) to monitor the testing of thermoelectric materials, either through a digital display as a graphic . The data acquisition system has a temperature accuracy to ± 2,5% to ± 2.5% voltage and current of ± 1.5%.
82

PROJETO, IMPLEMENTAÇÃO E AUTOMAÇÃO DE UMA BANCADA PARA ENSAIOS DE MOTORES A RELUTÂNCIA CHAVEADOS / PROJECT, IMPLEMENTATION AND AUTOMATION OF A BENCH FOR TESTING SWITCHED RELUCTANCE MOTORS

TEIXEIRA, Weldon Carlos Elias 30 June 2009 (has links)
Made available in DSpace on 2014-07-29T15:08:20Z (GMT). No. of bitstreams: 1 anexo dissertacao weldon.pdf: 502529 bytes, checksum: e010c8b9335a273bd3a0c2fd72779737 (MD5) Previous issue date: 2009-06-30 / This work presents a proposal for testing Switched Reluctance Motors, which is feasible by the design and construction of an automated test bench. The test proposal intends to measure phase s resistance; to compute copper loss; to obtain the magnetizing curves for aligned and unaligned rotor and a performance test, which is based on fixing the under test motor rotor speed by a drive machine that is drove by a frequency inverter. The computational automation is restricted in changing the d.c. voltage applied to the under test switched reluctance motor by a programmable sinusoidal voltage source; changing and/or fixing the under test rotation speed of the switched reluctance; changing the semiconductor-switch switching angle; acquisition and processing of the data obtained in the tests. Computational simulations were performed for validating tests results made in an available switched reluctance motor / Este trabalho apresenta uma proposta de ensaios de Motores a Relutância Chaveados, a qual se viabiliza através do projeto e construção de uma bancada automatizada. A proposta de ensaios compreende, entre outros procedimentos, em medir as resistências das fases; calcular a perda ôhmica; determinação das curvas de magnetização nas posições de pólos, do estator e rotor, alinhados e desalinhados e o desempenho, o qual se fundamenta na fixação da velocidade de rotação dos motores sob teste através de uma máquina de indução trifásica de grande potência comparada à potência do motor sob teste, cujo acionamento é realizado por meio de um conversor de freqüência. A automação realizada via computacional está circunscrita aos seguintes aspectos: variação da tensão de corrente contínua aplicada ao motor a relutância; variação e fixação da velocidade de ensaio do motor a relutância; variação do ângulo de disparo das chaves semicondutoras do conversor de potência; aquisição e processamento dos dados obtidos nos ensaios e determinação da velocidade do motor. Através do método dos elementos finitos foram realizadas simulações computacionais pertinentes para confrontar com os ensaios realizados em um motor a relutância chaveado disponível.
83

Estudo experimental e numérico do sistema de admissão de um motor de combustão interna / Experimental and numerical study of the intake system of an internal combustion engine

Gustavo Rodrigues de Souza 07 April 2010 (has links)
Durante o processo de admissão do ar em motores de combustão interna, nota-se que sua aspiração não é ideal, ou seja, o volume do cilindro não é completamente ocupado, devido à variação de sua massa específica e perdas de carga ao longo do sistema de alimentação. Conseqüentemente, a eficiência volumétrica no cilindro atinge valores ínfimos de desempenho, o que afeta diretamente a potência do motor. O trabalho consiste em um estudo numérico e experimental do sistema de admissão de um motor de combustão interna. A solução numérica foi obtida por um código comercial que resolve as equações de transporte, baseada nos princípios de conservação de massa, quantidade de movimento e energia, pelo método de discretização de volumes finitos. Os resultados numéricos foram validados através dos resultados obtidos em uma bancada experimental, que possibilitou medidas de vazão mássica, pressão e temperatura do ar admitido. A bancada é formada por um motor de combustão interna acionado por um motor elétrico e o estudo foi realizado sem a presença de combustível e por conseqüência sem a ocorrência de combustão. Através da utilização do software, demonstrou-se que foi possível construir um coletor inédito que proporcionou ao motor estudado um aumento de eficiência volumétrica de 6% a 3.500 rpm. / During the process of intake air in the internal combustion engine it has been noted that air flow is not ideal, i.e., the cylinder volume is not completely occupied concerning the variation of specific mass and the charge loss along the feed system. Consequently, the volumetric efficiency in the cylinder reaches low values of performance, affecting the engine power. The aims of this work were a numerical and experimental study of the intake manifold in an internal combustion engine. The numerical solution is obtained through a commercial code which solves the transport equations, according to the continuity, momentum and energy principles by the method of finite volume discretization. Numerical data were validated by the experimental results set-up, enabling the mass flow, pressure and temperature measures of the intake air. The flow bench is composed by an internal combustion engine turned on by an electric engine. The study was developed without fuel and combustion. Regarding the software, it was possible to build an original intake manifold which provides to engine studied an increase in the volumetric efficiency of 6% at 3,500 rpm.
84

Serra circular de bancada: proposta de um sistema de segurança

Ferreira, Carlos Martins 04 August 2015 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-07-27T15:08:57Z No. of bitstreams: 1 carlosmartinsmoreira.pdf: 3169148 bytes, checksum: b85043a0b599ad498b5ead3414a17edd (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-09T13:51:26Z (GMT) No. of bitstreams: 1 carlosmartinsmoreira.pdf: 3169148 bytes, checksum: b85043a0b599ad498b5ead3414a17edd (MD5) / Made available in DSpace on 2017-08-09T13:51:26Z (GMT). No. of bitstreams: 1 carlosmartinsmoreira.pdf: 3169148 bytes, checksum: b85043a0b599ad498b5ead3414a17edd (MD5) Previous issue date: 2015-08-04 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O Anuário Estatístico da Previdência Social (2013) publicou o registro de acidentes típicos de trabalho, apontando que as partes do corpo mais atingidas foram os ferimentos e fraturas do punho e da mão, totalizando juntos 16,5 % dos acidentes registrados no Brasil, fato recorrente desde o ano de 2007. Nesse sentido o objetivo da pesquisa é propor um sistema de segurança afim de proteger as mãos dos operadores da serra circular de bancada. Para isto, foi realizada uma revisão bibliográfica sobre o uso da madeira na construção, aspectos legais e culturais da segurança no trabalho e desenvolvimento de produto. Na pesquisa utilizou-se a metodologia estruturada de desenvolvimento do produto dos autores Ulrich e Eppinger, com algumas adaptações, seguindo os passos do planejamento e do desenvolvimento do produto. No planejamento realizou-se um check-list das condições de segurança na operação da serra circular para identificar as oportunidades do mercado e planejar o produto. No desenvolvimento do produto levantou-se as necessidades dos clientes (carpinteiros) que operam as serras em obras na cidade de Juiz de Fora (MG). Com as respostas obtidas, foram definidas as especificações alvo do produto, possibilitando a criação de conceitos, o rankeamento e a escolha do melhor conceito a ser desenvolvido. Um protótipo do sistema de segurança foi idealizado, instalando um sensor de presença infravermelho na coifa protetora e um freio que provoca a parada do motor da serra que foram interligados por meio de contatores. No teste do sistema foram utilizados um tacômetro e um osciloscópio digital para a aquisição de dados. O teste simulou a aproximação da mão do operador de encontro à zona de detecção do sensor de presença. Os resultados obtidos indicam como menor tempo de parada total do sistema de 100 milésimos de segundo e com este tempo calculou-se a distância de segurança para fixar o sensor de presença. Conclui-se que é necessário inovar a serra circular de bancada com um sistema de segurança eficiente e eficaz para aumentar a segurança dos operadores, e que a metodologia adotada, por ser um modelo genérico, permitiu a sua adaptação ao desenvolvimento do produto dessa pesquisa acadêmica e também proporcionou um ponto de partida para melhorias contínuas. / The Statistical Yearbook of Social Safety Insurance (2013) published the registry of typical labor accidents presenting that the most affected parts of the body were injuries and fractures on wrists and hands, together totaling 16.5% of the accidents recorded in Brazil, a recurring fact since 2007. In this sense, the aim of this research is to propose a safety system in order to protect the hands of circular bench saw operators. For this, a literature review on wood use on civil construction was carried out, legal and cultural aspects of labor safety and product development were also studied. In this research we used the structured methodology of product development idealized by the authors Ulrich and Eppinger with some adjustments, following the steps of planning and developing product. In the planning phase we developed a checklist of safety conditions in the circular saw operation in order to identify market opportunities and also to plan the product. In the product development phase we identified the consumer’s (carpenters) requirements of those who operates circular saws on civil construction in the city of Juiz de Fora (MG). With the responses obtained, we defined the specifications of the product, enabling concepts creation, as well as ranking and choosing the best concept to be developed. A safety system prototype was designed, in which was installed an infrared presence sensor in the protective hood along with a break that stop the saw motor, which were interconnected by contactors. In the system test we used a tachometer and a digital oscilloscope for data acquisition. The test simulated the operator’s hand approach in the presence sensor detection zone. The results showed that the shorter time for stopping the whole system was 100 milliseconds. We use this time to calculate the safety distance for placing the presence sensor. We concluded that it is necessary to innovate the circular bench saw with an efficient and effective safety system to increase the operators safety. It was also concluded that the methodology adopted, for configuring a generic model, allowed its own adaptation to the product development proposed by this academic research, providing a starting point for continuous improvements.
85

下側接近を特徴とする定置型イチゴ収穫ロボットの開発 / Development of a Stationary Robotic Strawberry Harvester with Picking Mechanism that Approaches Target Fruit from Below

山本, 聡史 24 January 2011 (has links)
This study explored the development of a stationary robotic strawberry harvester that was combined with a movable bench system as part of the development of an industrially production system for a strawberry in a plant factory. At first the difficulty of approaching target fruit was investigated using table-top plants cultured in a greenhouse. Then the maximum force needed to separate fruit from the peduncle was measured. Based on these results, an end-effector was designed with three unique functions; (1) suction cup was vibrated to minimize the influence of the adjoining fruits at the time of approach; (2) compressed air was blown toward the adjoining fruits to force them away from the target fruit; (3) peduncle was removed with the motion of tilting and pulling the target fruit. Next, an optical system to equip the machine with the ability to detect and determine the position and coloration of strawberry fruit was constructed. The position of the fruit was detected from below with a stereo-camera. The coloration measurement unit was set against the bed of the movable bench system at fruit level to capture images of target fruit. Considering the spectral reflectance characteristics of strawberry fruit, the coloration measurement unit was equipped with red, green, and white LEDs. Finally the stationary robot was tested in an experimental harvesting system in which the robot was combined with a movable bench unit. In the experiment system, the stationary robot enabled highly stable harvesting operation. / Kyoto University (京都大学) / 0048 / 新制・論文博士 / 博士(農学) / 乙第12528号 / 論農博第2747号 / 新制||農||988(附属図書館) / 学位論文||H23||N4584(農学部図書室) / 28350 / (主査)教授 近藤 直, 教授 清水 浩, 准教授 飯田 訓久 / 学位規則第4条第2項該当
86

Modelling of Test Bench for Road Load Simulation

Åberg Skender, Dennis January 2017 (has links)
Warehouse forklifts are often powered by batteries. By using a test bench where the forklift can be driven in a certain driving-cycle, the battery capacity can be tested. To obtain the same speed curve on the test bench as a forklift obtains when driving on a real road, the test bench must be able to simulate road load. In this master’s thesis, a test bench is modelled in Simulink using grey-box modelling and validated with measured data. Also, a speed regulator is developed and implemented in the test bench model to simulate road load. Simulations with the model and the speed regulator show high accuracy when compared against measured data. However, the results show that the pre-attached torque sensor is not optimally located, and that the gear oil temperature is of interest to measure to be able to model the friction torque as a function of the temperature. / Lagertruckar drivs ofta av batterier. Batterikapaciteten kan testas genom att använda en testbänk där trucken körs i en körcykel. För att simulera samma hastighetskurva på testbänken som trucken erhåller vid riktig körning på väg måste testbänken kunna simulera vägmotstånd. I detta examensarbete modelleras en testbänk i Simulink genom grey-box modellering och valideras med uppmätt data. Även en hastighetsregulator utvecklas och implementeras i modellen för att simulera vägmotstånd. Simuleringar med modellen och hastighetsregulatorn visar på hög träffsäkerhet jämfört med uppmätt data. Resultaten visar dock på att den monterade momentsensorn inte är optimalt belägen och att växeloljans temperatur är av intresse att mäta för att kunna modellera friktionen som en funktion av temperaturen.
87

MUSKULÄR STYRKA VID MULTIPLA REPETITIONER: : SKILLNADER VID STYRKETEST I BÄNKPRESS OCH LIGGANDE BÄNKRODD MED SKIVSTÄNGER AV OLIKA DIAMETEROMFÅNG

Westerberg, Martin January 2010 (has links)
Introduction: A complex interaction between muscles, tendons, bones, joints and nerves are required for optimal function of the human hand. It is known that an individual’s grip strength is vital for performance of physical demanding tasks such as strength training with free weights. Strength training including a thicker grip around the bar may enhance the strength of the grip in the athlete without other special routines for grip strength development. The purpose of this investigation was to examine the difference in performance in multiple repetitions in two strength training exercises using two different sizes on the bar, to look for correlations between grip strength of the subjects hand and the amount of repetitions executed with two different size of the bar and finally the correlation of hand size and the amount of repetitions executed with two different size of the bar. Method: 15 strength training men (23,9 ± 4,1 years), underwent measurements of hand size, maximum grip strength, 1 repetition maximum (1RM), a 80 % of 1RM weight strength test with two different  bar sizes. Results: The results from the present investigation indicates a 21,1 % reduction of 80 % of 1 RM weight performance in repetitions executed in the bench press with the thicker diameter of the bar and a 66,2 % reduction in repetitions executed with a 80 % of 1 RM weight in the lying bench row with the thicker diameter of the bar. The size of the hand or the maximum grip strength does not influences the performance in the 80 % of 1 RM strength test. Conclusion: With support of the results from this present investigation the size of the bar diameter significant influences the performance in maximum repetitions executed in a set in strength training with free weights, in a rowing exercise the repetitions executed reduced with 66,2 % and in the bench press the reduction of executed repetitions were 21,1 % with the thicker diameter of the bar. The size of the hand do not influences the performance of maximal executed repetitions with the thicker bar diameter. Maximal grip strength has no influence of the performance according to the findings of this investigation.
88

Tiered vs. Traditional Daily Undulating Periodization for Improving Powerlifting Performance in Trained Males

Vargas, Andres 23 March 2017 (has links)
Daily undulating periodization represents an increasingly popular trend in exercise science with which a traditional model has been established. Tiered daily undulating periodization pairs the DUP approach with a tiered training system which allows volume and intensity to be more evenly distributed throughout a given graining cycle. The concept of tiered daily undulating periodization is a novel form of periodization and has not been investigated. As such, a comparison of traditional and tiered daily undulating periodization has yet to be examined. Therefore, the purpose of this study was to compare the effects of traditional and tiered daily undulating periodization models as they relate to strength adaptations in trained males. Twenty-seven resistance trained males (22.0 ± 4.5 years) completed an 8 week resistance training protocol. Subjects were randomly assigned to either the traditional daily undulating periodization group (DUP, n = 12) or tiered daily undulating periodization group (TDUP, n = 15). Participants were recruited from the campus recreation center and met the minimum strength requirements of bench pressing their bodyweight, squatting 125% of their bodyweight, and deadlifting 150% of their bodyweight. Strength measures included squat 1RM, bench press 1RM, deadlift 1RM, powerlifting total, and Wilk’s Coefficient. Each variable was measured at baseline and again after the 8 week training period. Each group performed the same number of sets, reps, and exercises throughout each training week. DUP specified all exercises in a given training bout to be performed the same intensity and repetition scheme. TDUP specified performance of one high intensity exercise each day with each subsequent exercise being performed with lower intensity and differing repetition scheme. Data was analyzed via a 2x2 mixed factorial ANOVA with the alpha criterion for significance set at 0.05. There were no significant differences between groups at baseline and no significant differences were observed between groups for total volume or intensity. With respect to strength dependent variables, there was a main effect for time (p = <0.001) for back squat 1RM (DUP pre = 140.5 ± 33.9 kg, DUP post = 163.3 ± 29.8 kg; TDUP pre = 147.3 ±34.0 kg, TDUP post = 166.5 ± 30.7 kg), bench press 1RM (DUP pre = 104.2 ± 12.9 kg, DUP post = 114.9 ± 14.2 kg; TDUP = 110.4 ± 12.7 kg, TDUP post = 120.6 ± 11.9 kg), deadlift 1RM (DUP pre = 177.7 ± 26.4 kg, DUP post = 194.1 ± 20.2 kg; TDUP pre = 169.6 ± 37.5, TDUP post = 188.3 ± 37.5), powerlifting total (DUP pre = 422.4 ± 67.8 kg, DUP post = 472.4 ± 60.6 kg; TDUP pre = 427.1 ± 79.2 kg, TDUP post = 476.5 ± 74.1 kg), and Wilk’s score (DUP pre = 287.5 ± 49.3, DUP post = 320.0 ± 45.6; TDUP pre = 298.3 ± 45.8, TDUP post = 331.6 ± 38.7). However, no interaction effects were observed between DUP and TDUP for any of the strength dependent variables. These results suggest that 8 weeks of tiered DUP resistance training leads to similar gains in strength compared to the traditional DUP model in trained males. This could be a result of the similar workload between both groups. While not significant, traditional DUP may be more efficacious for improving back squat 1RM (DUP = 16%; TDUP = 13%), while TDUP may elicit greater strength gains in the deadlift (DUP = 9%; TDUP = 12%). Furthermore, this study demonstrates that exercise order and training intensity can be manipulated throughout each training session according to personal preference while maintaining strength adaptations within a DUP model. Lastly, dropout rates in this study lead researchers to conclude that the DUP protocols investigated should be transient and not used as a long term training approach.
89

Approche passive pour la modélisation, la simulation et l'étude d'un banc de test robotisé pour les instruments de type cuivre / Passive approach for the modelling, the simulation and the study of a robotised test bench for brass instruments

Lopes, Nicolas 15 June 2016 (has links)
Cette thèse s'inscrit dans le contexte de la robotique, de l'automatique et de l'acoustique musicale. Elle propose une étude d'un banc de test robotisé pour le jeu des cuivres et se décompose selon trois volets: la modélisation passive du système, sa simulation et son développement. La modélisation utilise le formalisme passif des systèmes hamiltoniens à ports. Les principaux éléments du système sont: l'alimentation en air pour le souffle, l'excitateur (composé de deux lèvres et d'un jet d'air) et un résonateur acoustique. Un nouveau modèle de jet d'air généré entre les lèvres est proposé. Ce modèle a pour but de restituer un bilan de puissance plus proche de la réalité physique que les modèles couramment utilisés. Pour la simulation à passivité garantie, la méthode du gradient discret est présentée. Elle ne garantit pas l'existence et l'unicité d'une solution et est limitée au second ordre de consistance numérique. De plus, son exécution nécessite des algorithmes d'optimisations non linéaires. Pour pallier ces limitations, une méthode à plusieurs étapes de type Runge-Kutta double et basée sur un changement de variable est proposée. Des résultats de simulations sont interprétés et comparés à ceux issus d'un modèle classique de la littérature. Le banc de test, ainsi que les développements techniques sont présentés. Ils permettent la mise au point d'expériences de cartographies répétables pouvant être utilisées pour caractériser différents instruments de musique. Enfin, des résultats numériques et expérimentaux sont comparés afin de mettre en avant les défauts et les qualités du modèle proposé. / This thesis is to be seen against the robotic, the automatic, and the musical acoustic backgrounds. It provides a study of a robotized test bench for brass instruments and is divided into three parts: the passive modelling of the system, its simulation and its development. The modelling uses a passive formalism, namely, the ports-Hamiltonian systems. The main parts of the complete system are: an air supply for the breath, an acoustic exciter (composed of a couple of artificial lip and an air jet) and an acoustic resonator. A new model for the air jet generated between the lips is proposed. This model aims at providing a power balance, which is closer to the real system than other commonly used models. The discrete gradient method is presented to perform passive simulations. It does not generally guaranty the existence and uniqueness of a solution and is limited to the second order of numerical consistency. Moreover, its execution needs nonlinear optimisation algorithms. To compensate for these limitations, a multi-stage method of double Runge-Kutta type and based on a change of variable is proposed. Results from simulations are interpreted and compared to those coming from a Bernoulli type model. Finally, the test bench and the technical developments are presented. They enable the performance of repeatable cartographies experiments which can be used to characterise music instruments. Finally, experimental and numerical results are compared in order to highlight the defaults and the qualities of the proposed model.
90

Évaluation sur banc d'essai des algorithmes des machines ventilatoires / Bench evaluation of the algorithms of ventilation treatment devices

Zhu, Kaixian 11 January 2016 (has links)
Les troubles respiratoires du sommeil, notamment le syndrome d’apnée du sommeil, représentent un problème de santé publique. Ils contribuent aux symptômes diurnes comme la somnolence sévère et sont associés à des maladies chroniques.Depuis quelques années, une variété d’appareils de traitement ventilatoire a été développée pour traiter les troubles respiratoires du sommeil, principalement les maladies liées à l’obstruction de la voie aérienne supérieure (apnée obstructive) ou à la commande centrale (apnée centrale). Ces appareils fonctionnent suivant des principes différents, en raison de leurs propres algorithmes, qui sont souvent mal connus et protégés par les fabricants. Les évaluations des appareils de ventilation sont effectuées pendant les traitements cliniques chez des patients. Il est donc difficile de comparer ces différents appareils dans les mêmes conditions à cause des variabilités inter- et intra-patient. Un banc d’essai pourrait permettre de tester les réponses des appareils dans les conditions standardisées et reproductibles.Cette thèse a consisté à construire un banc d’essai qui permet de reproduire les signaux de patients et de respecter de la physiologie humaine. La réaction du banc d’essai prend aussi en compte la réaction de l’appareil à tester sur le système, i.e., ce modèle fonctionne en « boucle fermée ». Avec le banc d’essai construit, les différentes machines de pression positive continue (PPC) autopilotée disponibles sur le marché ont été évaluées pour leurs algorithmes ainsi pour leurs modes confort. De plus, trois machines de ventilation auto-asservie (ASV) ont été soumises aux différents événements respiratoires du sommeil créés par un autre modèle d’un principe similaire. Nous avons montré que les machines de PPC autopilotée ne sont pas équivalentes pour l’efficacité du traitement et la précision des données du rapport. Les modes confort pourraient éventuellement dégrader l’efficacité du traitement de PPC si la pression thérapeutique n’est pas ajustée lors de leur introduction au traitement. Pour les machines ASV, leurs réponses ne sont pas suffisantes pour normaliser la respiration et les réglages des machines peuvent influencer l’efficacité du traitement. Les résultats pourraient compléter les données cliniques et fournir une option complémentaire pour le processus futur de certification de ces dispositifs médicaux. / Sleep disordered breathing including sleep apnea is a major public health problem. It contributes to daytime sleepiness and is associated with chronic diseases. In recent years, a variety of ventilation devices have been developed with the objective of treating sleep disorders related to the upper airway obstruction (obstructive apnea) or the central command (central apnea). These devices operate with different algorithms, which are little known and protected by the device manufacturers. Since most devices are evaluated during patient treatment, it is difficult to compare them in the same conditions due to inter- and intra-patient variability. Bench test has been proposed to evaluate the device responses in standardized and reproducible conditions. This thesis was aimed to develop a respiratory bench model able to reproduce patients’ signals and also in concordance with human physiology. The bench model can take into account the pressure responses of tested devices and works in a “closed loop” setting.With this bench model, several commercially available auto-titrating continuous positive airway pressure devices were evaluated for their auto-titration algorithms as well as their pressure-relief modes. Also, three adaptive servo-ventilation devices were evaluated by subjecting various sleep disordered breathing events that were generated by another bench model of a similar principle. We demonstrated that eleven auto-titrating continuous positive airway pressure devices were not equivalent in terms of their treatment efficacy and the data accuracy in the device report. The pressure-relief modes may attenuate the efficacy if not adjusted at the time of their introduction. The responses of adaptive servo-ventilation devices were not sufficient to normalize the breathing flow and their efficacy depended on the initial settings.The current certification process of these ventilatory devices, which focus mainly on clinical aspects, may be completed by the results of our bench.

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