Composite materials hold great potential for the replacement of traditional materials in machines utilized on a daily basis. One such example is within an engine block assembly where massive components inherently reduce the efficiency of the system they constitute. By replacing metal elements such as connecting rods, cylinder caps, or a crank shaft with composite alternatives, a significant increase in performance may be achieved with respect to mechanical strength, thermal stability, and durability, while also reducing mass. Exploration of this technology applied to a connecting rod geometry was investigated through a combination of process development, manufacturing, numerical analysis and testing. Process development explored composite material options based on experimental characterization, fabrication, and machining methods. Finite element analysis provided insight into model and data accuracy, as well as a basis for study on a unidirectional composite I-beam geometry. Destructive testing of the composite connecting rods provided data for a strength to weight ratio comparison with the original steel component. The composite connecting rods exhibited weight savings of 15%-17% that of the steel component. The rod made of woven composite material exhibited an elastic modulus of 68.1 Msi in its linear behavior before failure, thereby exhibiting a higher stiffness than the steel rod tested. Although the failure strengths were 25% below the required design load, the calculated strength to weight ratios showed favor for the composite alternatives.

Out-of-Autoclave (OoA) processes for manufacturing aerospace-grade parts needs to be better understood to further the development and success of industries that are manufacturing reusable launch vehicles, military and commercial aircraft, and spacecraft. Overcoming the performance limitations associated with OoA, also known as low-pressure prepreg curing, methods (void count, energy absorption, etc.) will help decrease the costs associated with aerospace composite manufacturing and the negative environmental effects correlated with high-pressure composite curing methods. Experimental, theoretical, and numerical approaches are used to explore both low and high-pressure curing cycles and how the two different processes affect final cured parts. Quasi-static uniaxial compression tests on 33mm diameter tubular specimens concluded that the high-pressure curing methods (up to 90 psi) increased the likelihood of a final part with increased stiffness compared to the lower atmospheric-pressure methods (14.7 psi) on an order of 22%. After further extension and deformation past the linear elastic region, tests concluded that although the autoclaved specimens may have been higher-quality parts, the low-pressure-cured specimens performed more efficiently with respect to energy absorption. Considering the specific energy absorption (SEA) and crush force efficiency (CFE) are both on average around 6% higher for the low-pressure specimens, it is concluded that they can perform similarly to the high-pressure specimens and possibly even more efficiently depending on the loading conditions and desired purpose of the structure.

The aim of the diploma thesis is the design of mechanical parts of the rear axle driveline suitable for rebuilding of a given sports car into an electric car. The introductory part briefly explains the physical principles of the drive and contains a brief summary of the current concepts of electric vehicle propulsion. Afterwards, there is a comparison and selection of a suitable concept for a given electric vehicle, determination of the basic vehicle parameters based on the calculation of the longitudinal vehicle dynamics and the gearbox calculation on the basis of which the design is solved. The next part is dedicated to the computational inspection of parts using the finite element method. The final part deals with the placement of the assembly inside the vehicle and the evaluation of the drive mechanism.

Master’s thesis is focused on a design of front uprights for Dragon 8 racing car of TU Brno Racing Formula Student team. This thesis follows up the bachelor’s thesis called “Race Car Front Wheel Carrier Design”. Discussion about team’s recent upright and component designs is followed by a model creation with use of topology optimization. Final geometry is simulated in FEA software. Design of the upright is then compared to the previous designs and also to its substitute produced with milling machining process.

This thesis deals with designing shape modifications of a toecap used in Honeywell brand safety shoes. The thesis shows algorithm of compression test and impact test FEA in ANSYS software. The toecap was divided into areas according to von-Misses stress. Several modifications were made in all areas separately, according to design of experiments. Best of the modifications were combined together and two best combinations selected. The goals were verified by experimental testing of manufactured toecaps. The results were even a little bit better than simulations.

This diploma thesis deals with the modelling of the piezoelectric composite material using the finite element method. The thesis is divided into three parts. Research study is done in the first part. It focuses on the possibility of use of the piezoelectric layers as sensors. The second part concerns the homogenization of MFC (macro fiber composite). Material and piezoelectric parameters are obtained by modelling elementary structural cell under different loading conditions. Determined characteristics are verified with experimental data. The third part proposes the design of the experimental device, which allows the simulation of the rotor excitation by rotating unbalance. Excitation responses of MFCs placed in specific locations are calculated using FEA model of the device. The conclusion includes the description of the suitability to vibration measurement on the device.

The aim of this diploma thesis is to analyse loading forces which impact on the frame of the disk plough-harrow during the real operation, suggestion and assembling of the measuring system for measuring of real loading. On the basis of this measuring to accomplish structural deformational tensor analysis of the frames load-bearing’s machine. In the introduction is shortly described using of the disk plough-harrow in modern agriculture. The diploma thesis is divided into two parts. The first part is devoted to the suggestion of the measuring system and loading measuring under real working conditions. The second part is focused on deformational tensor analysis of the frames load-bearing’s machine through the method of final elements. In conclusion it follows the evaluation of gained pieces of knowledge.

Syntactic foams are hollow particles-filled lightweight composites that are widely used in areas that require high strength while maintaining low weight and density. These foams are highly tailorable materials whose properties can be altered during the manufacturing process by changing various parameters like matrix and microballoon material type, size, distribution, as well as the volume fraction and wall thickness of microballoons. Therefore, understanding the effect of these parameter changes in the behavior of syntactic foams is very important to manufacture the foam for different applications. In the present study, syntactic foams of various volume fractions of microballoons were fabricated and different mechanical testing was conducted to study their elastic and viscoelastic behavior. Moreover, density, void content, and microstructure of the syntactic foam with varying volume fractions of microballoons were also studied to better characterize these foams. Results show that changes in the volume fraction of the microballoons had a significant impact on the elastic and viscoelastic behavior of the foams. The introduction of the microballoons into the epoxy resin decreased the density of the epoxy resin by up to 43.36% and at the same time increasing the specific modulus by up to 21.059%. In addition, representative 3D models of these syntactic foams were also developed to further study the elastic behavior of these materials which were found to be in good agreement with the experimental results. These findings will help in designing and optimizing the material properties of the syntactic foam required for different applications.

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A poroelastic finite element model of a heterogeneous articular cartilage disc was created to examine the tissue response to low amplitude (± 2% strain), low frequency (0.1 Hz) dynamic unconfined compression (UCC). A strong correlation has been made between the relative fluid velocity and stimulation of glycosaminoglycan synthesis. A contour plot of the model shows the relative fluid velocity during compression exceeds a trigger value of 0.25 μm/s at the radial periphery. Dynamic UCC biochemical results have also reported a higher glycosaminoglycan content in this region versus that of day 0 specimens. Fluid velocity was also found not to be the dominant physical mechanism that stimulates collagen synthesis; the heterogeneity of the fluid velocity contour plot conflicts with the homogeneous collagen content from the biochemical results. It was also found that a Tresca (shear) stress trigger of 0.07 MPa could provide minor stimulation of glycosaminoglycan synthesis. A feasibility study on modeling a heterogeneous disc was conducted and found convergence issues with the jump in properties from the superficial to middle layers of the disc. It is believed that the superficial layer contains material properties that allow the tissue to absorb much of the compressive strain, which in turn increases pressure and causes convergence issues in ABAQUS. The findings in this thesis may help guide the development of a growth and remodeling routine for articular cartilage.