As a musical instrument construction material, wood is both musically and aesthetically pleasing. Easy to work and abundant, it has traditionally been the material of choice. Unfortunately, wood is also a very inconsistent material. Due to great environmental and climatic variations, wooden specimens present large variations in their mechanical properties, even within species of a similar region. Surprisingly, an industry based entirely on acoustics has done very little to account for these variations. For this reason, manufactured wooden guitars are acoustically inconsistent. Previous work has shown that varying the dimensions of a guitar soundboard brace is a good method for taking into account variations in the mechanical properties of the wooden soundboard plate. In this thesis, the effects of a scalloped-shaped brace on the natural frequencies of a brace-plate system have been studied and tools have been developed in order to calculate the dimensions of the brace required to account for variations in the mechanical properties of the plate. It has been shown that scalloped braces can be used to modify two natural frequencies of a brace-plate system simultaneously. Furthermore, the most important criteria in modifying any given frequency of a brace-plate system is the mass and stiffness properties of the brace at the antinode of the given frequency’s associated modeshape. Subsequently, designing a brace for desired system natural frequencies, by taking into account the mechanical properties of the wooden plate, is an inverse eigenvalue problem. Since few methods exist for solving the inverse eigenvalue problem of general matrices, a new method based on the generalized Cayley-Hamilton theorem was proposed in the thesis. A further method, based on the determinant of the generalized eigenvalue problem was also presented. Both methods work well, although the determinant method is shown to be more efficient for partially described systems. Finally, experimental results were obtained for the natural frequencies of simply supported wooden plates, with and without a brace, as well as the inverse eigenvalue determinant method. Good correlation was found between theoretical and experimental results.

Establishing dynamic characteristics of structures is a challenging area of research. The dynamic characteristics of structures, such as natural frequencies, modeshapes, response levels and damping characteristics play an important role in identifying the condition of the structures. The assumed modes method is a particular analytical method used to estimate the dynamic characteristics of a structure. However, the eigenfunctions used in the assumed mode method often led to ill-conditioning due to the presence of hyperbolic functions. Furthermore, a change in the boundary conditions of the system usually necessitates a change in the choice of assumed mode. In this thesis, a set of Alternative Admissible Functions (AAF), along with penalty functions, are used to obtain closed form solutions for an Euler-Bernoulli beam with various boundary conditions. A key advantage of the proposed approach is that the choice of AAF does not depend on the boundary conditions since the boundary conditions are modelled via penalty functions. The mathematical formulation is validated with different boundary conditions, Clamped-Free (CF), Simply-Supported (SS), and Clamped-Clamped (CC). A specific relation between the penalty function and the system parameters are established for CF, SS and CC boundary conditions to obtain appropriate values of penalties. Validation of results with the reported literature indicates excellent agreement when compared with closed-form Euler-Bernoulli beam values. The AAF approach with penalties is extended to a beam with a shallow crack to estimate the dynamic characteristics. The crack is modelled as a penalty function via a massless rotational spring. This model has the advantage of simplifying parametric studies, because of its discrete nature, allowing easy modification in the crack position and depth of the crack. Therefore, once the model is established, various practical applications may be performed without reformulation of the problem. Validation of results with the reported literature on beams with shallow cracks indicates the suitability of the proposed approach.

Given the advantages of parallel manipulators and lightweight manipulators, a 3-PRR planar parallel manipulator with three lightweight intermediate links has been developed to provide an alternative high-speed pick-and-place positioning mechanism to serial architecture manipulators in electronic manufacturing, such as X-Y tables or gantry robots. Lightweight members are more likely to exhibit structural defection and vibrate due to the inertial forces from high speed motion, and external forces from actuators. Structural flexibility effects are much more pronounced at high operational speeds and accelerations. Therefore, this thesis presents the dynamics and vibration control of a 3-PRR parallel manipulator with three flexible links. Firstly, a procedure for the generation of dynamic equations for a 3-PRR parallel manipulator with three flexible intermediate links is presented based on the assumed mode method. The dynamic equations of the parallel manipulator with three flexible intermediate links are developed using pinned-pinned boundary conditions. Experimental modal tests are performed using an impact hammer and an accelerometer to identify the mode shapes, frequencies, and damping ratios of flexible intermediate links. The mode shapes and frequencies, obtained from experimental modal tests, match very well the assumed mode shapes and frequencies obtained based on pinned-pinned boundary conditions, and therefore the dynamic model developed is validated. Secondly, this thesis presents the investigation on dynamic stiffening and buckling of the flexible links of a 3-PRR parallel manipulator by including the effect of longitudinal forces on the modal characteristics. Natural frequencies of bending vibration of the intermediate links are derived as the functions of axial force and rigid-body motion of the manipulator. Dynamic stiffening and buckling of intermediate links is investigated and configuration-dependant frequencies are analyzed. Furthermore, using Lagrange multipliers, the fully coupled equations of motions of the flexible parallel manipulator are developed by incorporating the rigid body motions with elastic motions. The mutual dependence of elastic deformations and rigid body motions are investigated from the analysis of the derived equations of motion. Open-loop simulation without joint motion controls and closed-loop simulation with joint motion controls are performed to illustrate the effect of elastic motion on rigid body motions and the coupling effect amongst flexible links. These analyses and results provide valuable insight into the design and control of the parallel manipulator with flexible intermediate links. Thirdly, an active vibration control strategy is developed for a moving 3-PRR parallel manipulator with flexible links, each of which is equipped with multiple PZT control pairs. The active vibration controllers are designed using the modal strain rate feedback (MSRF). The amplification behavior of high modes is addressed, and the control gain selection strategy for high modes is developed through modifying the IMSC method. The filters are developed for the on-line estimation of modal coordinates and modal velocity. The second compensator is used to cut off the amplified noises and unmodeled dynamics due to the differentiation operation in the developed controller. The modal coupling behavior of intermediate links is examined with the modal analysis of vibrations measured by the PZT sensors. The error estimation of the moving platform is examined using the measurement of PZT sensors. Finally, an active vibration control experimental system is built to implement the active vibration control of a moving 3-PRR parallel manipulator with three flexible links. The smart structures are built through mounting three PZT control pairs to each intermediate flexible link. The active vibration control system is set up using National Instruments LabVIEW Real-Time Module. Active vibration control experiments are conducted for the manipulator moving with high-speed, and experimental results demonstrate that the vibration of each link is significantly reduced.

Given the advantages of parallel manipulators and lightweight manipulators, a 3-PRR planar parallel manipulator with three lightweight intermediate links has been developed to provide an alternative high-speed pick-and-place positioning mechanism to serial architecture manipulators in electronic manufacturing, such as X-Y tables or gantry robots. Lightweight members are more likely to exhibit structural defection and vibrate due to the inertial forces from high speed motion, and external forces from actuators. Structural flexibility effects are much more pronounced at high operational speeds and accelerations. Therefore, this thesis presents the dynamics and vibration control of a 3-PRR parallel manipulator with three flexible links. Firstly, a procedure for the generation of dynamic equations for a 3-PRR parallel manipulator with three flexible intermediate links is presented based on the assumed mode method. The dynamic equations of the parallel manipulator with three flexible intermediate links are developed using pinned-pinned boundary conditions. Experimental modal tests are performed using an impact hammer and an accelerometer to identify the mode shapes, frequencies, and damping ratios of flexible intermediate links. The mode shapes and frequencies, obtained from experimental modal tests, match very well the assumed mode shapes and frequencies obtained based on pinned-pinned boundary conditions, and therefore the dynamic model developed is validated. Secondly, this thesis presents the investigation on dynamic stiffening and buckling of the flexible links of a 3-PRR parallel manipulator by including the effect of longitudinal forces on the modal characteristics. Natural frequencies of bending vibration of the intermediate links are derived as the functions of axial force and rigid-body motion of the manipulator. Dynamic stiffening and buckling of intermediate links is investigated and configuration-dependant frequencies are analyzed. Furthermore, using Lagrange multipliers, the fully coupled equations of motions of the flexible parallel manipulator are developed by incorporating the rigid body motions with elastic motions. The mutual dependence of elastic deformations and rigid body motions are investigated from the analysis of the derived equations of motion. Open-loop simulation without joint motion controls and closed-loop simulation with joint motion controls are performed to illustrate the effect of elastic motion on rigid body motions and the coupling effect amongst flexible links. These analyses and results provide valuable insight into the design and control of the parallel manipulator with flexible intermediate links. Thirdly, an active vibration control strategy is developed for a moving 3-PRR parallel manipulator with flexible links, each of which is equipped with multiple PZT control pairs. The active vibration controllers are designed using the modal strain rate feedback (MSRF). The amplification behavior of high modes is addressed, and the control gain selection strategy for high modes is developed through modifying the IMSC method. The filters are developed for the on-line estimation of modal coordinates and modal velocity. The second compensator is used to cut off the amplified noises and unmodeled dynamics due to the differentiation operation in the developed controller. The modal coupling behavior of intermediate links is examined with the modal analysis of vibrations measured by the PZT sensors. The error estimation of the moving platform is examined using the measurement of PZT sensors. Finally, an active vibration control experimental system is built to implement the active vibration control of a moving 3-PRR parallel manipulator with three flexible links. The smart structures are built through mounting three PZT control pairs to each intermediate flexible link. The active vibration control system is set up using National Instruments LabVIEW Real-Time Module. Active vibration control experiments are conducted for the manipulator moving with high-speed, and experimental results demonstrate that the vibration of each link is significantly reduced.

Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2017-10-02T13:28:16Z No. of bitstreams: 1 Caroline Teixeira Ortega_.pdf: 915980 bytes, checksum: 9bda19ffbc0b4e1743cc4b67ea718cd5 (MD5) / Made available in DSpace on 2017-10-02T13:28:16Z (GMT). No. of bitstreams: 1 Caroline Teixeira Ortega_.pdf: 915980 bytes, checksum: 9bda19ffbc0b4e1743cc4b67ea718cd5 (MD5) Previous issue date: 2017-03-24 / Nenhuma / Os calçados femininos exercem importante papel na vida das mulheres à medida que representam símbolos como poder, elegância e sensualidade. O amor declarado por calçados é comumente percebido na sociedade e pode ser compreendido como o resultado de um conjunto de experiências emocionais positivas vividas pelas mulheres. Dessa forma, o calçado é visto como pertencente a um sistema que engloba elementos que transcendem os aspectos físicos do produto. Sob o âmbito de sistema-produto, este estudo objetivou analisar as experiências femininas de dez mulheres de 20 a 53 anos com seus calçados declarados amados a partir de uma análise de appraisals. Esta análise foi realizada através de Análise de Conteúdo, que possibilitou relacionar dez categorias empíricas aos sete componentes do modelo componencial da Teoria dos Appraisals. Este estudo permite compreender os gatilhos emocionais que levaram as entrevistadas desta pesquisa a amarem seus sapatos. Contudo, também como resultado, este trabalho apresenta elementos que poderão contribuir aos designers para projetar calçados que possam vir a se tornar amados pelo público feminino. Dessa forma, esta pesquisa contribui para os estudos sobre calçados femininos e para a área de design emocional. / Female shoes have important role in women’s life as they represent symbols of power, elegance and sensuality. Shoes assumed love is commonly seen in our society and can be understood as a result of a set of positive emotional experiences lived by women. In this way, the shoe is perceived as belonging in a system that encompasses elements that transcend the physical aspects of the product. Under the product system scope, this study aimed to analyze experiences of ten women from 20 to 53 years old with their loved shoes from an Appraisals analysis. This analysis was made by content analysis, that enabled to conceive empiric categories which were related to seven appraisals components of Appraisals Theory. This study enable to understand the positive emotional triggers that resulted in the love by shoes. Thereby, as a result, this study relates elements which can contribute to designer to design shoes which can become loved shoes by women. Therefore, this research also contributes to women’s shoes studies and for emotional design area.

La simulation numérique par la méthode des éléments finis (MEF) fournit de nos jours une grande aide pour les ingénieurs dans les processus de conception d’optimisation des produits. Malgré le développement croissant des ressources de calcul, la fiabilité et l’efficacité des simulations numériques par la MEF restent à améliorer. Ce travail de thèse consiste à développer une famille d’éléments solide-coque (SHB) pour la modélisation tridimensionnelle des structures minces. Cette famille d’éléments SHB est basée sur une formulation tridimensionnelle en grands déplacements et rotations. La technique dite “d’intégration réduite dans le plan”, en utilisant un nombre arbitraire de points d’intégration dans la direction de l’épaisseur, permet la modélisation des structures minces avec une seule couche d'éléments. Dans ce travail de thèse, deux éléments linéaires SHB prismatique et hexaédrique, ainsi que leurs contreparties quadratiques, ont été implantés dans le code par éléments finis ABAQUS pour l’analyse quasi-statique et dynamique des structures minces. La performance de ces éléments a été validée à travers une série de cas tests académiques, ainsi que sur des problèmes complexes de type impact/crash et des procédés de mise en forme de tôles minces. L'ensemble des résultats numériques obtenus révèle que les éléments SHB représentent une alternative intéressante aux éléments coques et solides traditionnels pour la modélisation tridimensionnelle des structures minces. / Nowadays, the finite element (FE) simulation provides great assistance to engineers in the design of products and optimization of manufacturing processes. Despite the growing development of computational resources, reliability and efficiency of the FE simulations remain the most important features. The current work contributes to the development of a family of assumed strain based solid-shell elements (SHB), for the modeling of 3D thin structures. Based on reduced integration and special treatments to eliminate locking effects and to control spurious zero-energy modes, the SHB solid‒shell elements are capable of modeling most thin 3D structural problems with only a single element layer, while describing accurately the various through-thickness phenomena. In the current contribution, a family of prismatic and hexahedral SHB elements with their linear and quadratic versions have been implemented into ABAQUS using both standard/quasi-static and explicit/dynamic solvers. The performance of the SHB elements is evaluated via a series of popular benchmarks as well as with impact/crash and sheet metal forming processes. All numerical results reveal that the SHB elements represent an interesting alternative to traditional shell and solid elements for the 3D modeling of thin structural problems.

Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-08-24T00:22:08Z No. of bitstreams: 1 DISSERTA??O UEFS-1.pdf: 4397842 bytes, checksum: 5bbf7864e46035d01b3cd15d9b25b50d (MD5) / Made available in DSpace on 2016-08-24T00:22:08Z (GMT). No. of bitstreams: 1 DISSERTA??O UEFS-1.pdf: 4397842 bytes, checksum: 5bbf7864e46035d01b3cd15d9b25b50d (MD5) Previous issue date: 2016-04-01 / It is important to emphasize that both the quality of the water as the quantity and regularity of supply are determining factors for the emergence of diseases in humans. Therefore, we used the epidemiological ecological study, quantitative, in order to assess the consumption of rainwater and the incidence of diarrhea in children under 5 years of age: the exposed, which use capture systems roof rain water which is stored in tanks for potable purposes, composed of 111 children of the city of Lowland Ro?a-Ba; and not exposed, which use public water supply, composed also by 111 children of the city of Baixa Grande-Ba. Health indicators were adopted that diarrhea and measured over a period of 90 days. They were applied form, spreadsheet and field observation form with the families and children participating in the survey. The analysis of data obtained from said diarrhea and measured showed a significant association between episodes of diarrhea in the total sample of children studied and the spatial distribution where the highest concentrations occurred. Children who drank rain water had higher risk in percentage and time of occurrence, to have episodes of diarrhea than children who drink tap water, but with a difference not very acentuda. The incidence in children who consume rainwater stored in cisterns was 11.1%, and 5.8% in families who drink tap water. / ? importante ressaltar que tanto a qualidade da ?gua quanto a sua quantidade e regularidade de fornecimento s?o fatores determinantes para o surgimento de doen?as no ser humano. Portanto, utilizou-se o estudo epidemiol?gico do tipo ecol?gico, de natureza quantitativa, a fim de avaliar o consumo de ?gua da chuva e a incid?ncia de diarreia em crian?as menores de 5 anos de idade: as expostas, as quais utilizam sistemas de capta??o de ?gua de chuva do telhado e que ? armazenada em cisternas para fins pot?veis, compostas por 111 crian?as da cidade de V?rzea da Ro?a?Ba; e as n?o expostas, as quais utilizam ?gua da rede p?blica de abastecimento, compostas, tamb?m, por 111 crian?as da cidade de Baixa Grande-Ba. Os indicadores de sa?de adotados foram diarreia referida e mensurada, durante um per?odo de 90 dias. Foram aplicados formul?rio, planilha e ficha de observa??o de campo junto ?s fam?lias e crian?as participantes da pesquisa. A an?lise dos dados obtidos da diarreia referida e da mensurada apresentou uma associa??o significante entre os epis?dios de diarreia na amostra total de crian?as estudadas e na distribui??o espacial onde ocorreram as maiores concentra??es. As crian?as que beberam ?gua de chuva apresentaram maior risco, em percentual e tempo de ocorr?ncia, de ter epis?dios de diarreia do que as crian?as que bebem ?gua da rede p?blica, por?m com uma diferen?a n?o muito acentuda. A incid?ncia nas crian?as que consomem ?gua da chuva armazenada em cisternas foi de 11,1%, e de 5,8% nas fam?lias que bebem ?gua da rede p?blica.

Cette thèse s’intéresse au développement d’éléments finis solide–coques dédiés à la modélisation de structures multicouches sollicitées en vibrations. En effet, la plupart des modèles multicouches dans la littérature présentent des limitations dans certaines configurations géométriques et matérielles. Face à ce constat et dans un souci de proposer un outil moins coûteux en temps de calcul, nous avons proposé une approche basée sur le concept solide–coques. Il s’agit d’éléments finis tridimensionnels dont le comportement a été amélioré par l’Assumed Strain Method. Dans un premier temps, nous avons formulé le problème de vibrations de structures sandwichs à cœur viscoélastique. La dépendance en fréquence a ainsi été prise en compte en utilisant une loi constitutive complexe. Pour résoudre le problème discrétisé, la Méthode Asymptotique Numérique, couplée à l’homotopie, et utilisant l’approche DIAMANT, a été adoptée pour les excellents résultats qu’elle offre par rapport aux autres méthodes. Des tests ont permis de valider les modèles proposés et de montrer l’avantage par rapport aux éléments ayant la même cinématique. Poursuivant nos travaux, et dans un souci d’augmenter l’amortissement, nous nous sommes orientés vers un contrôle actif des vibrations. Pour ce faire, deux éléments finis piézoélectriques ont été formulés. Il s’agit des éléments SHB8PSE et SHB20E qui sont des extensions des éléments finis SHB8PS et SHB20, respectivement. Le couplage électromécanique a consisté en l’ajout d’un degré de liberté à chacun des nœuds des dits éléments. Quelques exemples en statique et en vibrations menés sur des structures multicouches allant de simples poutres aux structures présentant des non-linéarités géométriques ont permis de valider les éléments solide–coques proposés. Pour finir, une synthèse des acquis des chapitres 2 et 3 a permis de proposer une modélisation de structures multicouches comprenant des couches élastiques, viscoélastiques et piézoélectriques. À l’amortissement passif provenant du pouvoir amortissant des matériaux viscoélastiques, on ajoute un contrôle actif qui découle du courant électrique généré au cours de la déformation des couches piézoélectriques. Ainsi, un filtre a été installé entre les capteurs et actionneurs. Ce filtre permet d’amplifier ou d’atténuer le potentiel électrique généré dans le but de réduire les amplitudes de vibrations. Pour résoudre le problème résultant nous avons étendu le solveur utilisé au chapitre 2. Pour valider les modèles proposés, des tests de contrôle actif–passif ont été menés sur des structures plaques multicouches. Enfin, quelques lois de contrôle découlant de filtres ont permis de montrer comment cette procédure permet de réduire ou même d’éviter l’amplification des vibrations / This thesis deals with the development of solid–shell finite elements for vibration modeling of multilayer structures. Indeed, most of multilayer models in the literature show some limitations in certain geometric and material configurations. Considering these restrictions and in order to develop a more efficient calculation tool, we proposed an approach based on the solid–shell concept. This consists of three-dimensional finite elements enhanced through the Assumed Strain Method. First of all, we have formulated the problem of vibrations of sandwich structures with viscoelastic core. The frequency dependence has been taken into account by using a complex constitutive law. To solve the discretized problem, the Asymptotic Numerical Method, coupled with the homotopy technique and the DIAMANT toolbox approach, was adopted due to the excellent results it provides compared to other methods. Benchmark tests have validated the models and highlighted their advantages over existing elements having the same kinematics. In order to increase damping properties, we directed our attention towards an active vibration control. For this purpose, two piezoelectric finite elements have been developed. These finite elements SHB8PSE and SHB20E are extensions, of the elements SHB8PS and SHB20, respectively. The electromechanical coupling consisted in adding an electrical degree of freedom to each node of these elements. A variety of test problems both in static and vibration analysis conducted on multilayer structures ranging from simple beams to structures involving geometric nonlinearities allowed validating the proposed solid–shell elements. Finally, combining the achievements made in chapters 2 and 3, we proposed a modeling approach for multilayer structures composed of elastic, viscoelastic and piezoelectric layers. Active control is introduced using the piezoelectric properties in order to improve the reduction in vibration amplitudes. Thus, a filter has been mounted between the sensors and actuators. This filter allows amplifying or attenuating the generated electric potential in order to reduce the vibration amplitudes. To solve the resulting problem, we extended the resolution method used in chapter 2. To validate the proposed models, active–passive control tests have been conducted on multilayer plate structures. Finally, some control laws, associated with filters, have shown how this procedure can allow reducing or even avoiding amplification of vibrations

Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2017-06-23T12:48:13Z No. of bitstreams: 1 Dimitrius Boatini_.pdf: 1175657 bytes, checksum: 8cf2ab094f0559a8e82d1b550209f300 (MD5) / Made available in DSpace on 2017-06-23T12:48:13Z (GMT). No. of bitstreams: 1 Dimitrius Boatini_.pdf: 1175657 bytes, checksum: 8cf2ab094f0559a8e82d1b550209f300 (MD5) Previous issue date: 2017-03-07 / Nenhuma / O trabalho estuda o tão polêmico conceito de ativismo judicial, sujeito a inúmeras definições, mas aqui entendido como a ingerência do poder judiciário nas áreas de competências precípuas dos poderes legislativo e executivo, em conjunção com a responsabilidade civil do estado por omissão inconstitucional no que tange aos direitos fundamentais, em especial, no que diz respeito a um dos principais desdobramentos da nova responsabilidade civil; o nexo causal presumido. Para isso um primeiro capítulo será dedicado em estudar de maneira central em relação à responsabilidade civil, não somente em seu contexto histórico e tradicional, mas com todos os desdobramentos da atualidade que surgem como uma complexidade a mais tão somente passível de ser resolvida com a via do ativismo judicial. O segundo capítulo envolverá todas as conceituações, críticas e argumentos a favor do ativismo judicial, bem como a definição de seu conceito para efeitos deste trabalho; além da análise dos mais diversos casos práticos da jurisprudência do Supremo Tribunal Federal. Se evidencia uma necessidade de ativismo judicial para a satisfação dos direitos fundamentais, amparado por ampla doutrina, porém, com uma série de parâmetros que possibilitem que o mesmo seja utilizado de maneira adequada; como a diferenciação entre o juízo de probabilidade do nexo causal presumido e a teoria do risco integral, utilização da teoria da causa eficiente em detrimento da mais tradicional teoria da causa direta e imediata utilizada pelo Judiciário nacional, e o maior auto-comedimento do Judiciário nos casos envolvendo um confronto de direitos fundamentais. / The essay is about the controversial figure of Judicial Activism, that is defined under a wide array of concepts, but here will be treated as the judiciary acting on the legislative and executive competencies, in conjunction with the civil responsibility of the state for unconstitutional omissions on the fundamental rights, especially with the one of the most relevant new consequences from the civil responsibility in its new figure, the assumed causal link. For this to happen, the first chapter will study the civil responsibility in a deep and thoughful manner, not only on its traditional and historical scope, but also with the contemporary events that unfold and change the law in a way that only judicial activism can bring an answer to it. The second chapter will bring all the concepts and positions about the judicial activism, besides define what is the concept that this essay will use. The essay ends with the idea that the judicial activism is necessary for the fulfilling of the fundamental rights, such as numerous authors had already advocated, but theres a wide array of guidelines created for it to be used in an adequated manner, like, being able to differentiate the probability judgement from the assumed causal link theory from the full risk theory from the state, the use of the theory of the efficient cause instead of the direct and immediate cause, and a bigger use of the judiciary self-restraint when the case in question brings a clash from fundamental rights.

Internal combustion engines are used in many applications. The same engine type may have different components mounted to it depending upon its use. These engine mounted components need to be designed against fatigue in order to withstand the engine vibrations. Measured engine vibrations are commonly used as input data for fatigue estimation. The focus in this thesis is set on heavy-duty diesel engines, typically used in trucks, buses and industrial applications. All of the appended papers use engine vibration measurements to evaluate the proposed methods. In Paper A, the engine block motion is described with a seven degree of freedom kinematic model. These degrees of freedom consist of six rigid body modes and one assumed twisting degree of freedom. With this description, measured engine block vibrations can be used to accurately predict the vibration in positions that have not been measured. Relating the measured vibrations of an engine mounted component with the projected motion of the engine block at that same position, makes it possible to identify local dynamic phenomena. In Paper B, the kinematic model of Paper A is extended with three assumed bending deformation mode shapes. For the current engine type, all of the assumed deformation modes are ranked within the 10-300 Hz frequency range. The deformation mode of highest importance is the engine block twist. Including bending deformation increases the accuracy of the engine block vibration description but it also increases the demands on instrumentation. In Paper C, the possibility to modify measured engine vibration signals, for addition or removal of engine mounted components, is investigated. For this purpose, engine vibration measurements were performed with and without a 29 kg brake air compressor mounted to the engine. For the task of removing the effect that this engine mounted component has on the engine block, the two cases of knowing, and not knowing the vibration of the component are both considered. The proposed methodology successfully predicts the changes in engine vibration due to system modification. The proposed method can also be used to estimate the time response of a component's centre of gravity. In this study the component's dynamic properties are derived from measurements but they could also be produced using finite element analysis. This can be useful early in the design process to find critically stressed areas due to base excitation. / <p>QC 20171222</p>