This Master’s thesis is focused on the suspension of the front wheel, more accurately for specific part, upright. It describes the basic requirements for construction, distribution of uprights, their method of production and types of materials used. It briefly mentions topology optimization and its two optimization methods. Also deals with vehicle dynamics for driving conditions – standing vehicle, braking and cornering. In the practical part, the work is focused on determining the load effects on the upright during the aforementioned driving conditions using MBS software. At the end of the work, FEM stress and deformation analyses are performed for loading on the wheel side and on the suspension side, which are then compared and evaluated.

Diploma thesis Selected measurements of the motion of bicycles – braking and ridein the curve analyses problematic manoeuvres of bicycle riders according to the most typical accidents including bikes. There will be given statistics of bikers´ participation on accident amount that happened within last few years. The measurements of bicycles moving around bands of specific radiuses as a situation of most bicycle accidents will be described in the next part of this thesis. There will be also specified the values of average bicycle speeds when driving in curves with various radiuses according to types of bicycles, sex and experiences of the riders and will be an output of this thesis. Further on there will be measurements of braking in the direct line on various surfaces with different types of bikes and different brakes used.

The diploma thesis focuses especially on a design of a way for evaluating roughness in road profile, which affects driving characteristics of a car and a ride. In the theoretical part of the thesis are mentioned the most used methods and tools for road roughness analysis in the world. For the purposes of this thesis an experimental measuring were undertaken in order to obtain data for the own design of a road profile analysing system.

Orientador: André Luiz Andreoli / Resumo: Nos últimos anos, questões relacionadas ao meio ambiente, principalmente, ao uso de combustíveis fósseis e à emissão de gases poluentes na atmosfera, ganharam grande destaque internacional. Com os avanços da comunidade científica e o aumento no preço do petróleo no começo da década de 1970, o uso de fontes renováveis, não poluentes e limpas teve grande investimento por parte de diversos países. Nesse contexto, a geração eólica vem se destacando como uma das mais promissoras, especialmente devido a sua viabilidade econômica e ao seu rápido desenvolvimento tecnológico. Entre as diferentes topologias utilizadas nos sistemas de geração eólica, destaca-se a configuração elaborada para operação em velocidade variável, que emprega o gerador de indução duplamente alimentado (DFIG), associado ao conversor eletrônico back-to-back para controle de sua operação. Como principais vantagens da utilização do DFIG, destacam-se sua maior eficiência na conversão de energia, menor estresse mecânico do rotor, controle independente de potência ativa e reativa limitada a valores típicos de 30% da potência nominal. Por outro, sabe-se que, durante a ocorrência de um distúrbio, as correntes do rotor podem atingir altas magnitudes e causar danos ao conversor. Além disso, sobretensões no capacitor do elo CC ocorrem devido à perda de capacidade de transferência de energia do conversor do lado da rede. Entretanto, os aerogeradores podem ser requisitados a permanecerem em funcionamento mesmo durante uma fa... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In the last years, issues related to the environment, especially the use of fossil fuels and the emission of polluting gases into the atmosphere, have gained great international prominence. With the advances of scientific community and the increase of the oil price in the beginning of the 1970s, the use of renewable, non-polluting and clean sources had a great investment by several countries. In this context, wind generation has stood out as one of the most promising, especially due to its economic viability and its fast technological development. Among the different topologies used in wind generation systems, the configuration developed for operation at variable speed is highlighted, which employs the doubly-fed induction generator (DFIG) associated with back-to-back electronic converter to control its operation. The main advantages of using DFIG include its greater efficiency in energy conversion, less mechanical rotor stress, independent control of active and reactive power limited to typical values of 30% of the rated power. On the other hand, it is known that, during the occurrence of a disturbance, such as an electrical fault, the rotor currents can reach high magnitudes in order to damage the rotor side converter. In addition, overvoltages in the DC link capacitor occur due to the loss of power transfer capacity on grid side converter. However, wind turbines may be required to main in operation even during a fault, in addition to contributing the restoration of voltage... (Complete abstract click electronic access below) / Mestre

The purpose of this study is to provide a historiographical and musical analysis examining the jazz ride cymbal pattern, from its inception on woodblock, small accessory cymbals, hand cymbal mechanisms and brushes through what becomes known as the modern-day ride cymbal pattern. This research examines a wide array of drummers and bandleaders, with the objective of identifying the earliest recordings of this important addition to jazz drumming, and popular music history while analyzing the ride cymbal pattern's evolution through definitive recordings. The study begins with the earliest known recordings that clearly display the pattern as it is played on any of the instruments mentioned above. The research concludes with the jam sessions of the early 1940s at Minton's Playhouse, where the pioneer of bebop drumming, Kenny Clarke, experimented with altering the pattern. At this point, the pattern reach its final level of maturity and has since experienced no subsequent major modification. The historical and geographical analysis uses relevant literature from the field of jazz history in order to interpret and evaluate the impact of the the overall trajectory of the music and players. By surveying newspaper and magazine articles, archival interviews, and photographic sources, combined with audio and film analysis, it is clear that drummers navigated a path to the maturation of the pattern.

As new requirements for grid connected generators were implemented, the requirements for evaluating the Fault Ride Through capabilities of the generators became stricter. When refurbishing a power unit, proof that the power unit meet the requirements must be submitted to the authorities. Performing simulations of the Fault Ride Through of a production unit is an extensive process and requires advanced simulation models and tools. Therefore, the need for a simplified tool for estimating the Fault Ride Through capability arose, which is what the project produced. Also, knowledge of which production module characteristics (such as the generator parameters, transformer and excitation system) have the largest effect on the Fault Ride Through time, would also be beneficial. Through the creation of Simulink simulation models of two hydropower stations and a sensitivity analysis of station parameters, the relative effect of the parameters on the Fault Ride Through time is estimated and implemented into a time independent Fault Ride Through time estimation tool, based on the Equal Area criterion. The purpose of the time-independent Fault Ride Through time estimation tool is to provide an insight into the approximate transient stability of the hydropower station and which parameters affect the performance the most. Simulations show that the transient reactance of the generator, the generator inertia, the transient time constant and the transformer inductance have the largest effect on the Fault Ride Through capability. The results show that a simplified tool cannot estimate the Fault Ride Through as accurately as a time-domain simulation model can.

A growing body of international research on urban transport shows that women from all over the world are experiencing safety issues within today’s transport systems. Furthermore, these reports shed light on and discuss how gender bias within the transport sector contributes to this problem. To design future mobility services that everyone will use and enjoy, it is thus important to understand women’s travel needs and to involve a diverse group of users in the development process. With a vision of shaping mobility for a sustainable future NationalElectric Vehicles Sweden (NEVS) is developing a mobility solution consisting of connected, autonomous, and electrified vehicles designed and optimized for shared mobility within city environments. To address this issue in NEVS service this thesis applied an exploitative research approach to examining factors that affect women’s willingness to share rides with others(potential strangers) in a context where there is no driver physically present. The methodology, inspired by the ’Design Thinking’ framework consisted of two main phases:(I) Problem definition and (II) Concept development. To understand women’s safety issues within today’s transport system and frame the design challenge an extensive literature study covering the topics of women’s safety in public transport, technology acceptance, trust, and human-centered design was conducted. To further define user needs and encourage the end-users to take an active role in co-designing solutions for themselves two focus group workshops were held. The initial research and the results from the workshops further formed the basis for the subsequent Concept Development phase. A need for control over the shared travel situation revealed by the participants’ great demand for information led this phase to examine passengers' needs in relation to an In-Vehicle Information System (IVIS). Two prototypes were developed and further tested together with users to evaluate the proposed solutions. The results showed that the anthropomorphic system features used to create a more human-like interaction had a positive impact on the participants’ overall user experience and their perceived safety during a ’shared ride’ scenario. Having a female voice communicating system information made the participants feel less nervous, more comfortable, and more secure compared to when the same information was communicated solely by a visual interface. Other factors that had a major impact on the user experience in general and the perceived security were perceived Ease of Use (PEOU) and freedom of choice. The results showed how not understanding how to interact with the vehicle’s physical features had a negative impact on perceived safety while freedom of choice such as being able to book a specific seat in the vehicle is indicated to have a positive impact on people’s willingness to share their journey with a stranger.

The present thesis aims to establish ideas and technical solutions that can have a positive impact on women's perceived safety while traveling in autonomous vehicles, made for sharing with strangers. The method follows the Design Thinking model which contributes to a user-centered design approach. Initial literature research was performed to understand the problem area, which included women's issues in public transportation, the development of autonomous vehicles, the foundation of a trusting behavior and authentication technologies for identifying users. Following ideation workshops with eight potential users of the service contributed with ideas based on the female perspective and their expectations of traveling in a shared mobility alternative. These results provide a foundation that contributes to a specific purpose of the thesis to create and evaluate strategies for authentication of co-passengers due to being advocated by the participants. Two versions of a high-fidelity mobile application prototype were created in Figma with different strategies for how to interact with the service and authentication methods to align with the autonomous vehicle prototype provided by NEVS during the following tests.  The final user tests, with 14 participants, indicate that an identification method should be included in the service, especially during the night. Six of seven female participants appreciate a combination of Bank ID while requesting a ride and facial recognition when boarding the vehicle. However, the results of the male participants vary to a larger extent. The results do not indicate where the identification technology should be implemented, in the private phone or the vehicle doors. To create a solution available to a larger target group, the mobile application need to adopt and provide option alternatives regarding identification methods due to individual differences and previous experiences which lays a foundation for the users' ability to contribute to a trusting behavior. Furthermore, an onboarding process for the first-time user is proposed to prepare the user and describe how the service could be used and what is expected by them.

Active anti-roll bars have recently found greater acceptance among premium car manufacturers and optimal application of this technology has emerged as an important field of research. This thesis investigates the potential of implementing active anti-roll bars in a passenger vehicle with the purpose of increasing customer value. For active anti-roll bars, customer value is defined in terms of vehicle’s ride comfort and handling performance. The objective with this thesis is to demonstrate this value through development of a control algorithm that can reflect the potential improvement in ride comfort and handling. A vehicle with passive anti-roll bars is simulated for different manoeuvres to identify the potential and establish a reference for the development of a control algorithm and for the performance of active anti-roll bars. While ride is evaluated using single-sided cosine wave and single-sided ramps, handling is evaluated using standardized constant radius, frequency response and sine with dwell manoeuvres.The control strategy developed implements a combination of sliding mode control, feed forward and PI-controllers. Simulations with active anti-roll bars showed significant improvement in ride and handling performance in comparison to passive anti-roll bars. In ride comfort, the biggest benefit was seen in the ability to increase roll damping and isolating low frequency road excitations. For handling, most significant benefits are through the system’s ability of changing the understeer behaviour of the vehicle and improving the handling stability in transient manoeuvres. Improvement in the roll reduction capability during steady state cornering is also substantial. In conclusion, active anti-roll bars are undoubtedly capable of improving both ride comfort and handling performance of a vehicle. Although the trade-off between ride and handling performance is significantly less, balance in requirements is critical to utilise the full potential of active anti-roll bars. With a more comprehensive control strategy, they also enable the vehicle to exhibit different driving characteristics without the need for changing any additional hardware.

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