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This study ventures into the intricate realm of aero engine mount systems, delving into the design and optimization of these crucial components. Our research utilizes mathematical modeling, computational algorithms, and a well-coordinated integration of Python scripting with Computer-Aided Design (CAD) tools to explore the design space of engine mounts, aiming to optimize their performance. Specifically, the study targets the optimization of certain design variables - L1, θ1, θ2, θ3, and R - that characterize the physical properties and performance of the engine mount system. The Python script computes the optimal values for these variables, which are then inputted into a CAD program, enabling the visualization and analysis of the optimized design. One of the fundamental objectives of this study was to minimize the forces experienced within the links of the engine mount system. The optimization procedure focused on the balance and distribution of forces across the links, ensuring that no single link was subjected to an undue portion of the load. The successful achievement of this objective not only improved the structural integrity of the engine mount system, but also underscored the potential of targeted optimization strategies in enhancing the performance of these critical components. By reducing the forces within the links, the study was able to contribute to the overarching goal of improving the overall distribution of loads in the separate links of the aero engine mount structure. The optimization objectives of this study also include minimizing the overall weight of the engine mount system, reducing backbone bending, and minimizing deflections through the reduction of the radial component. The results demonstrate the successful accomplishment of these objectives within the set boundaries, paving the way for enhancements in the structural rigidity and reliability of the engine mount system. Lastly, the study underscores the potential of leveraging computational optimization tools, such as the Python scripting and the L-BFGS-B algorithm. The outcomes of this study offer essential insights that could guide future design and optimization processes of engine mounts, laying a robust groundwork for further exploration in this field. Future work may include extending this methodology to larger engines with different behaviors and scales.  For those intrigued by the computational aspect of this investigation and keen to delve deeper into the intricacies of the code employed, Appendix A provides a comprehensive view. The Python script utilized in this study, integral to the optimization process, is included in its entirety in this section.

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Researchers are trying to find a solution for reducing the vibration of the engine with minimum changes to the engine mounts. Several researches and main giant car companies have presented valuable effort in these areas but still new research is needed to improve the control system. The present research carried out a comprehensive study of the state of art methods to suppress unwanted vibration from the engine to the passenger cars. This research was designed based on the objective of the Trelleborg Company to investigate the influence of Active Vibration Control (AVC) on the real engine. Therefore, this thesis tried to challenge the vibration problem with practical engineering approach by implementing different types of controllers experimentally and applying them on the real petrol engine. Inversing controlling technique and PID controller tuned with different methods (Ziegler Nichols and tyreus-luyben) have been tested here on two separate platforms; unbalanced DC motor and petrol engine. In addition, as a requirement of the study, the resonance frequency and related mode shapes of the system was investigated experimentally. It is also shown that using suitable filters can help elimination of high frequency noises in the control signals. This study experimentally tests PID controller with mentioned tuned methods on a real engine with this specific setup for the first time. A new scheme was developed with "mode shapes specific controller system", according to which the shaker position and the controller parameters were specified according to the system mode shapes. The result of applying controllers shows that both control methods have a similar effect on vibration reduction. A 33% - 37% reduction on DC motor achieved in different frequencies (20Hz, 37.5Hz and 46.2Hz) with different control methods, and about 10% reduction on petrol engine at resonance frequency while the shaker IV40 (with max 30N force) was placed on the chassis. For reducing the vibration transmitted from the engine to the chassis, for the first time the shaker was placed on the engine (unlike in previous studies where the shaker was placed on the chassis). Using shaker IV40 placed on the engine results in a 20% reduction in vibration transmission, which is a significant improvement in comparison with having the shaker on the chassis. The optimum result was achieved using shaker IV45 (Max 50N force), which yielded a vibration reduction of 33%.

The thesis deals with the issue of replacement of the Rotax 912 ULS engine with the Rotax 915 iSc3 B engine and its impact on flight performance, characteristics and airframe loads of the WT 9 Dynamic. For accomplish better maneuverability tail surfaces are enlarged. Both versions of airplane with different engines and tails surfaces are quantified with respect to airframe loads and flight characteristics. The output of the diploma thesis can be used for strength design of airplane structure and stress tests of the new modification of the WT 9 Dynamic aircraft.

<p>Achieving better NVH (noise, vibration, and harshness) comfort necessitates the use of active technologies when product targets are beyond the scope of traditional passive insulators, absorbers, and dampers. Therefore, a lot of effort is now being put in order to develop various active solutions for vibration control, where the development of actuators is one part. </p><p>Active hydraulic engine mounts have shown to be a promising actuator for vibration isolation with the benefits of the commonly used passive hydraulic engine mount in addition to the active ones. In this thesis, a benchmark of actuators for active vibration control has been carried out. Piezoelectric actuators and electromagnetic actuators are studied further and two methods to estimate parameters for electromagnetic actuators have been developed. A parameterized model of an active hydraulic engine mount valid for frequencies from zero to about 300 Hz, has also been developed. Good agreement with experimental data has been achieved.</p>

Achieving better NVH (noise, vibration, and harshness) comfort necessitates the use of active technologies when product targets are beyond the scope of traditional passive insulators, absorbers, and dampers. Therefore, a lot of effort is now being put in order to develop various active solutions for vibration control, where the development of actuators is one part. Active hydraulic engine mounts have shown to be a promising actuator for vibration isolation with the benefits of the commonly used passive hydraulic engine mount in addition to the active ones. In this thesis, a benchmark of actuators for active vibration control has been carried out. Piezoelectric actuators and electromagnetic actuators are studied further and two methods to estimate parameters for electromagnetic actuators have been developed. A parameterized model of an active hydraulic engine mount valid for frequencies from zero to about 300 Hz, has also been developed. Good agreement with experimental data has been achieved.

Automotive engine mounts are used to support engine weight, protect engine from road inputs and isolate transmission of vibrations created by the engine, which has a drastic effect on the noise generated inside the passenger cabin. Most common types of engine mounts are elastomeric and hydraulic mounts, the former having better vibration isolation characteristics whereas the latter displays better shock isolation. Elastomeric mounts are widely used for their low initial cost, while hydraulic mounts with inertia track and decoupler are chosen for their good vibration isolation and shock excitation characteristics. However, hydraulic mounts with inertia track and decoupler are not appropriate for small segment and commercial vehicles due their high initial cost. In this thesis, the effect of the addition of a dry friction damper on the performance of elastomeric automobile engine mounts is investigated. Friction dampers are used to attenuate vibration amplitudes in many applications such as gas turbine engines, railway vehicles, space structures and civil buildings. In this study, a friction element is added to the engine mount at its axial direction and its effect is studied. Results show that, the addition of dry friction damping to the original system increases vibration isolation performance significantly at low frequencies / whereas, due to the increased stiffness of the system, at high frequencies dry friction damper has a mitigating effect on performance. In order to overcome this problem, original system parameters are modified. In the modified system a softer mount that increase vibration isolation performance at high frequencies / but, which might cause excessive static deflection due to reduced stiffness of the system is used. On the other hand, addition of dry friction damping prevents excessive static deflections due to the increased stiffness effect and also increases the performance at high frequencies due to the soft mount. Final results showed that vibration isolation performance at low frequencies increases considerably while vibration isolation performance at high frequency is similar and even slightly better than the original system with addition of dry friction damping.

The topic of the thesis is a design of an aicraft for towing of gliders. Based on the background research of the towing aircrafts currently used by the Czech aeroclubs and the analysis of the required characteristics of these aircrafts the design of the new airplane has been created. Moreover, the load of engine mount has been determined according to the CS-VLA directive (a certification guidelines for the Very-light aircrafts). Its construction design as well as strength calculation have been elaborated. The part of the thesis is a 3D model of the aircraft and the engine mount.

The main aim of this diploma thesis is to evaluate and select the most appropriate option how to mount a power unit in Formula Student vehicle. It assesses an overall dynamic behaviour of a drive unit mounted in student formula. At the end of the final thesis is an assessment of proposed engine mount variants. The study of parameters that most influence engine vibrations can be seen there.