Thesis (M.S.)--University of Wisconsin -- La Crosse, 2009. / Includes bibliographical references.

Com o advento da crise do petróleo na década de 70, os motores, que antes eram calibrados para fornecer máximos torque e potência, após a crise passaram a ser calibrados de forma a fornecer consumo específico e emissões mínimos. A partir de então os motores passaram a ser ensaiados em bancadas dinamométricas que possuíam módulo para medição de emissões e que simulavam condições mais reais de tráfego, segundo um ciclo de ensaios preestabelecido. Este trabalho contém um levantamento bibliográfico sobre o instrumental, metodologias e procedimentos utilizados nos ensaios dinamométricos permanentes e dinâmicos e propõe a implementação de uma metodologia para realização de ensaios em tempo real controlado por computador. Traz também os resultados experimentais relativos à parte da metodologia que foi implementada. / With the advent of petroleum crisis in the 70\'s, engines, previously calibrated in order to supply maximum momentum and power, after the crisis they started being calibrated to supply minimum specific consumption and emissions. After this, engines started being tested in dynamometric benches equipped with emission measure modules and that simulate traffic conditions closer to reality, according to a prior emissions cycle. This work contain a bibliographic survey about instruments, methodologies and procedures used in the steady-state and dynamic dynamometric tests and proposes the implementation of a methodology to perform real time tests controlled computationally. It brings too experimental results related to the implemented methodology.

Strength and tone of the pelvic floor muscles are thought to play an important role in pelvic floor disorders, and are key outcomes monitored in pelvic floor rehabilitation, yet the standard approach to measuring these outcomes is through subjective assessment using manual palpation. While intravaginal dynamometers (IVD) have been designed to measure these characteristics in research settings, most are not sufficient to withstand the rigors of clinical use. This work presents the bench validation and subsequent updated design of a new mechanical constant speed mechanism for future inclusion in an IVD. Opening speeds of the original mechanism were validated with and without external loading using video analysis. The bench validation showed that the speed of arm opening was lower than the ranges specified for clinical use and was influenced by external loading. The mechanism was updated, and the bench test was repeated. The updated mechanism was found to provide output speeds that are within the ranges required clinically and were minimally impacted by external loading. The next step of this work is to reduce the size of the mechanism and improve output speeds to allow it to be assembled into a clinical prototype IVD.

The Army's Fire Resistant Fuel (FRF) program is currently being used to defend against the threat of vehicle fuel fires resulting from unconventional warfare encountered in the Middle East. Fire Resistant Fuels are based upon JP-8, which is now the primary fuel for the Army ground services. The goal of FRF development is to reduce susceptibility to ignition at standard storage conditions while still serving as a fuel for the Army's diesel vehicles. Two preliminary tests were conducted to narrow down a field of candidates developed by Luna Innovations to a final set of five FRF. Dynamometer testing was used to determine peak power of the supplied Yanmar 2V750 engine. Fuel fire resistance characteristics were defined and compared using a rotating disk anti-misting characterization system. Fuels were characterized based upon spray characteristics including velocity and droplet diameter as well as through ignition testing. For these tests, FRF were compared to Diesel and Jet-A results. Results from this testing has shown that two fuels, both JP-8 emulsions, met the basic criteria of a fire resistant fuel. Engine testing trends showed that both fuels surpassed the peak power output of Diesel. Rotary atomization ignition testing resulted in no ignition for both fuels. As a supplementary study, cone calorimetry testing was performed to determine effective heats of combustion. Results from experimentation demonstrated that the energy content of the FRF is not of primary importance to engine performance or flame resistance. All data, analysis and trends are located in the appendices. / Master of Science

Advance Vehicle Technology Competitions (AVTCs) have been around for 30 years. Since 1994, the Hybrid Electric Vehicle Team (HEVT) at Virginia Tech has participated in AVTCs to pursue hybrid technologies. HEVT participated in a four-year AVTC called EcoCAR 3. At the beginning of the competition, HEVT introduced an ultra-rapid onboarding process, the Independent Study (IS) program, to involve non-seniors with the team. Although the IS program provides an incredible experience to non-seniors, it lacks hands-on experience related to the actual work students do once they become full-fledged team members. The challenge is to introduce two hands-on supplemental projects: the energy storage system (ESS) and the motor system. Each project is considered low voltage (LV) for safety and simplicity, however high voltage techniques are used for learning purposes. The LV ESS is used to power up an LV motor system. To limit depletion of the battery energy, another LV motor system is used as a generator to recharge the LV ESS. The lead faculty advisor, Dr. Douglas Nelson, and the project manager, Andres Coello, are working in congruence to introduce a smooth transition of the projects into HEVT's IS program. The hands-on projects are expected to last one semester. The goals are to guide students in the design, construction and testing of both systems. The hands-on supplemental projects are also meant to aid the Applied Automotive Engineering (AAE) curriculum by filling important knowledge gaps current AAE modules are missing. / Master of Science / The Hybrid Electric Vehicle Team of Virginia Tech has participated in Advanced Vehicle Technology Competitions since its inception in 1994. These competitions challenge universities to reengineer and convert a vehicle into a hybrid vehicle. The goal is to train the next generation of automotive students by providing real world engineering experiences. The latest Advanced Vehicle Technology Competition is a four-year competition called EcoCAR 3. Due to complexity of the project, the Hybrid Electric Vehicle Team introduced an onboarding process to recruit and teach students the required knowledge of hybrid vehicles. To further improve the program, two projects are created to provide hands-on experience and visual learning about the electric layout of a hybrid vehicle. The first project is a low voltage battery pack and the second project is a low voltage motor dynamometer system. Both projects complement each other, meaning the battery pack acts as a power supply to the motor system. Overall, these projects are chosen to provide a good understanding to incoming students in the onboarding process about batteries and motors. Finally, practices used by the Hybrid Electric Vehicle Team are implemented in the project designs to improve the overall experience of students in the onboarding process and to improve knowledge transfer.

No description available.

Abstract Decreased adductor muscle strength has been shown to be a risk factor for the development of future groin injury. The purpose of this study was therefore to examine standard values of isometric adductor muscle strength in Swedish male soccer and to map any differences in muscle strength between non-injured players and previously injured players. Twenty-one male soccer players were included in the study. A handheld dynamometer was used to record maximal isometric adductor muscle strength. The average value for isometric adductor muscle strength for all included players was 2,709 N/kg [± 0,37 SD]. Average values for non-injured and previously injured players were 2,716 N/kg [± 0,41 SD] and 2,537 N/kg [± 0,25 SD] respectively. The average value for the contralateral, non-injured side within the previously injured players was 2,86 N/kg [± 0,43 SD]. The difference in muscle strength between previously injured players and non-injured players was not statistically significant (p = .162). Conversely the difference between the non-injured side and the injured side in previously injured players was statistically significant (p = .018). Future studies should focus on including players of different levels to conclude whether the differences observed in this study is present regardless of the level of play.

Bakgrund En handhållen dynamometer (HHD) är ett kliniskt användbart mätverktyg för att mäta muskelstyrka. På Akademiska sjukhuset i Uppsala finns en HHD av märket MicroFET2® (Hoggan Scientific). Det finns ett fåtal studier gjorda som undersöker intrabedömarreliabiliteten vid mätningar av isometrisk muskelstyrka av knäledens muskelgrupper med denna dynamometer. Syfte Syftet med studien var att undersöka den absoluta och relativa reliabiliteten vid mätningar av maximal muskelstyrka i knäledens muskelgrupper med en HHD. Metod Psykometrisk design med test-retest förfarande. Totalt undersöktes 24 friska vuxna vid två mättillfällen med 6–8 dagars mellanrum. Den relativa reliabiliteten presenterades med Intraclass correlation coefficient (ICC 2,1). Den absoluta reliabiliteten presenteras i standard error of measurement (SEM), SEM% samt smallest detectable change (SDC). Resultat Resultaten visade mycket hög relativ reliabilitet för knäledens extensioner (ICC = 0,950,96) och för knäledens flexorer (ICC = 0,94–0,96). SEM varierade mellan 33,58N-34,81N för knäledens extensorer och 14,16N-17,16N för knäledens flexorer. SDC varierade mellan 93,08N–96,49N för knäledens extensorer och 39,25N-47,57N för knäledens flexorer. Konklusion Resultaten indikerar att HHD har mycket hög relativ reliabilitet för bedömning av styrka i knäledens stora muskelgrupper hos ett bekvämlighetsurval med friska vuxna människor.  Den relativa och absoluta reliabiliteten bedömdes överlag vara i enlighet med tidigare studier. För implementering i klinik behöver framtida studier utvärdera absolut och relativ reliabilitet på specifika patientpopulationer. / Background Hand held dynamometry (HHD) is a practical device for testing muscle strength. There is currently a HHD (MicroFET2® - Hoggan Scientific) available at Uppsala University hospital. Few reliability studies excist where the objective is to examine the intra-rater reliability of isometric maximal knee-strength using this device. Objective To examine the absolute and relative reliability of isometric maximal knee-strength using a MicroFET2. Method Psychometric design through test-retest with 6–8 days between measures on 24 healthy adults. The relative reliability expressed as Intra-class correlation coefficient (ICC 2,1) and the absolute reliability as standard error of measurement (SEM), SEM%, and smallest detecatble change (SDC). Results The results of this study showed very good reliability for both knee extensors (ICC = 0,950,96) and knee flexors (ICC = 0,94–0,96). Regarding the absolute reliability SEM ranged from 33,58N-34,81N for knee extensors and 14,16N-17,16N for knee flexors. SDC ranged from 93,08N-96,49N for knee extensors and 39,25N-47,57N for knee flexors. Conclusion The results indicate that HHD has a very good relative reliability for assessing strength in the large muscle groups of the knee joint when examined on a group of healty adults. The relative and absolute reliability was generally in accordance when compared with previous studies. Before being implemented in praxis, future studies need to evaluate absolute and relative reliability on specific patient populations.

A dinamometria isocinética é um método seguro e fidedigno de avaliação da força, trabalho e potência dos grupos musculares e representa o padrão ouro na avaliação em cadeia cinética aberta. Com os avanços tecnológicos, a avaliação isocinética tornou-se uma ferramenta muito utilizada para avaliação do desempenho muscular tanto em estudos biomecânicos como clínicos. O objetivo deste estudo foi realizar revisão sistemática da literatura sobre avaliação isocinética do quadril, com ênfase nos parâmetros metodológicos associados e melhor reprodutibilidade, especificamente: posicionamento do paciente, do eixo do dinamômetro e do braço de alavanca no momento do exame; velocidade angular e tipo de contração. Foi realizada uma pesquisa bibliográfica sistematizada nas bases de dados eletrônicas Cochrane, LILACS, PEDro, PubMed e SciELO. Os critérios de inclusão foram: artigos que avaliaram a força da musculatura do quadril com o dinamômetro isocinético e que continham análise de reprodutibilidade ICC ou PCC dos testes. Foram encontrados 148 artigos selecionados nas bases de dados eletrônicas, deste total foram selecionados 20 estudos que avaliaram isocineticamente a musculatura do quadril, após a pré-seleção dos artigos, os mesmos foram subdivididos em 3 grupos de acordo com o movimento realizado pelo quadril: Grupo 1 treze artigos avaliaram o movimento de flexão e extensão; Grupo 2 nove artigos avaliaram abdução e adução; Grupo 3 seis artigos avaliaram rotação interna e externa, um total de 1137 indivíduos foram submetidos à avaliação isocinética do quadril. Em cada Grupo selecionaram-se os artigos que obtiveram melhor resultado de reprodutibilidade, cujos parâmetros metodológicos foram avaliados. Conclusão: Para obter melhor reprodutibilidade da avaliação isocinética da musculatura flexora e extensora do quadril, o indivíduo deve ser posicionado em decúbito dorsal com o eixo do dinamômetro alinhado no trocânter maior do fêmur. A fixação do braço de alavanca posicionada na região mais distal possível da coxa. A velocidade angular utilizada para análise de pico de torque e trabalho muscular 60°/s e para avaliação da potência muscular 180°/s e as contrações analisadas concêntricas e excêntricas. Na avaliação isocinética da musculatura abdutora e adutora do quadril, o indivíduo deve ser posicionado em decúbito lateral com as costas voltada para o dinamômetro, o eixo do dinamômetro posicionado na intersecção de duas linhas retas, sendo a primeira linha a partir da EIPS até o joelho e a segunda linha medial ao trocânter maior do fêmur em direção à linha média do corpo. A fixação do braço de alavanca posicionada na região distal da coxa. A velocidade angular utilizada para análise de pico de torque e trabalho muscular 30°/s e para avaliação de potência muscular 210°/s. As contrações analisadas foram concêntricas e excêntricas. Na avaliação isocinética dos rotadores internos e externos, o indivíduo testado posicionou-se sentado com eixo do dinamômetro alinhado com a linha articular do joelho, com a fixação do braço de alavanca na região distal da tíbia. A velocidade angular mais utilizada para análise de pico de torque e trabalho muscular foi de 30°/s e para avaliação da potência muscular foi 210°/s, as contrações analisadas também foram concêntricas e excêntricas. / Isokinetic dynamometry is a safe and reliable method for assessing the force, work and power of muscle groups and is the \"gold standard\" in the evaluation of muscle strength in the open kinetic chain. With technological advances, isokinetic evaluation has become a widely used tool to evaluate muscle performance in biomechanical as well as in clinical studies. The objective of this study was to systematically review the literature on isokinetic evaluation of the hip, with emphasis on methodological parameters associated to better reproducibility, specifically: patient positioning, dynamometer axis and lever arm during the evaluation; angular speed and type of contraction. A literature search was carried out systematically in electronic databases Cochrane, LILACS, PEDro, PubMed and SciELO. The inclusion criteria were papers on the evaluation of the hip muscles strength with an isokinetic dynamometer and papers that analyzed the ICC or PCC reproducibility test. 148 papers were found in electronic databases and of this total were selected 20 studies that evaluated isokinetically the muscles of the hip, after pre-selection, they were divided into 3 groups according to the movement performed by the hip: Group 1 - thirteen papers evaluated the flexion and extension; Group 2 - nine papers evaluated abduction and adduction; Group 3 - six papers evaluated internal and external rotation, a total of 1137 subjects underwent isokinetic evaluation of the hip. In each Group were selected items that obtained better results reproducibility, whose methodological parameters were evaluated. In conclusion: in order to obtain better reproducibility of isokinetic evaluation of the flexor and extensor muscles of the hip: the individual must be positioned in the supine position and the dynamometer axis must be aligned in the greater trochanter of the femur. The positioning of the lever arm must be in the most distal region of the thigh possible. The angular speed used to analyze torque peak and muscle work was 60°/s, and to evaluate the muscle power was 180°/s, and contractions analyzed concentric and eccentric. In isokinetic evaluation of the abductor and adductor muscles: the individual must be positioned in the side-lying position with your back toward the dynamometer and the dynamometer axis must be aligned with the intersection of two straight lines, with the 1st line from the posterior-superior iliac spine to the knee and the 2nd line medial to the greater trochanter of the femur toward the midline of the body. The positioning of the level arm must be in the most distal region of the thigh. The speed used to analyze torque peak and muscle work was 30°/s, and to evaluate the muscle power it was 210°/s, with concentric and eccentric contractions being analyzed. In isokinetic evaluation of internal and external rotators: the individual must be positioned in the sitting position and the dynamometer axis must be aligned with the line knee joint. The positioning of the level arm must be in the distal region of the tibia. The speed used to analyze torque peak and muscle work was 30°/s, and to evaluate the muscle power it was 210°/s, with concentric and eccentric contractions being analyzed.

The Motor Systems Resource Facility (MSRF) at Oregon State University presently conducts a variety of steady state tests on Motors and Generators, with ratings of upto 300Hp.(225kW), using a dynamometer. The dynamometer consists of an induction motor fed by a power electronic converter. A control computer uses a serial link, to send the desired steady state values of speed or torque to the converter. The objective of the work of this thesis was the conversion of the existing control interface, to one that could support programmable dynamic operation. Some of the capabilities that the resulting system has acquired, include the ability to simulate a general, predefined torque or speed profile, from a generalised polynomial function, a sine wave of torque or speed added to a constant offset, and a general purpose mode which allows the user to specify an atypical profile. The conversion to dynamic operation, permits the study and laboratory simulation of dynamic effects like the Sub-Synchronous Resonance phenomenon observed in turbine- generator sets attached to the power grid, the effect of "tower shadow" on wind power generation, time-varying load profiles, testing of machines under real world operating situations etc. Several tests were performed to ensure that the actual speed/torque profiles obtained from the machine, corresponded to the reference profiles specified in each case. Measured performance of specific examples is given. / Graduation date: 1999