Att ta fram en ny bilmodell är ett tidskrävande och omfattande arbete där många olika kunskapsområden måste samspela. En del i utvecklingsprocessen som får allt större betydelse är designarbetet. Om bilens utförande och design inte tilltalar konsumenterna innebär detta låga försäljningssiffror och därmed förlorade intäkter för företaget. Det huvudsakliga syftet med detta arbete är att grundligt undersöka om och hur CAD-programmet Catia V5 med modulen Imagine & Shape (IMA) skulle kunna användas på Volvo Car Corporations designavdelning (PVS). Syftet är också att granska vad en implementering av Catia V5 med IMA-modulen skulle innebära för produktutvecklingsprocessen, samt att undersöka vilka som skulle kunna använda sig av programmet. För att undersöka hur Catia V5:s IMA-modul skulle kunna fungera på PVS har vi i samarbete med designstuderande Pontus Ny modellerat en konceptbil, komplett med exteriör, instrumentpanel, mittkonsol, ratt, stolar, baksäte, fälgar och hjul. Vi har även modellerat en växelspak och en backspegel som först har tagits fram i Alias, vilket har möjliggjort en jämförelse mellan Alias och Catia V5:s IMA-modul. Modellerna har sedan utvärderats genom enkäter med uppföljande intervjuer. Urvalsguppen utgörs av ett antal anställda hos PVS som har haft möjlighet att sätta sig in i IMA-modulen. Respondenterna uppgav fördelar som anmärkningsvärd snabbhet vid framtagning av 3D-modeller i de fall där ytan inte behöver vara perfekt. Dock krävs stor erfarenhet för att skapa en bra renhet och ytjämnhet vid stora ytor. Samtliga involverade i detta projekt anser också att Catia V5 med IMA-modulen skulle kunna fungera som ett konceptgenereringsverktyg i ett tidigt skede. Att använda IMA-modulen i den första förberedande fasen skulle enligt vår mening innebära tidsbesparingar, eftersom användaren snabbt kan genomföra förändringar på en modell redan på möten. I dagsläget måste en Alias-modellör samla in alla ändringar, genomföra dessa snabbast möjligt och därefter bestämma en tid för ett nytt möte då alla inblandade kan närvara, vilket sällan är enkelt. IMA-modulen skulle även kunna vara ett bra hjälpmedel för en designer, som själv kan modellera sina idéer och därigenom lättare åskådliggöra och diskutera sitt koncept vid möten. I många fall är det enklare att förstå en 3D-modell som man kan vrida och vända på, än en ritning på ett papper. Utifrån IMA-modellen skulle det vara möjligt att fräsa ut en lermodell, vilken kan finjusteras och sedan åter scannas in och bearbetas vidare i Alias.

Nickel-Titanium (NiTi) shape memory alloys have been the focus of extensive research due to its unique characteristics such as high recoverable strain and ductility. However, solutionized samples of NiTi do not demonstrate good shape memory characteristics due to low strength for dislocation slip. Thermo-mechanical treatments are required to strengthen the matrix and improve the shape memory characteristics. Plastic deformation and the subsequent annealing is the common way to improve shape memory properties. In this case, deformation magnitude, temperature, rate, mechanism, and annealing temperature and time are all important parameters for the final shape memory properties. Equal channel angular extrusion (ECAE) is a well-known technique to severely deform materials by simple shear with no change in cross-section. In this study, Ti- 49.8 at% Ni samples are deformed by ECAE at three different temperatures near transformation temperatures. X-ray analysis, calorimetry, transmission electron microscopy and thermo-mechanical cycling techniques are utilized to investigate the effects of severe deformation and subsequent annealing treatment on shape memory properties. Martensite stabilization, formation of strain induced B2 phase, change in transformation temperatures, formation of new phases, recrystallization temperature, texture formation, and increase in strength and pseudoelastic strain are the main findings of this study. Co-32.9 at% Ni-29.5 at% Al is a newly found ferromagnetic alloy. Its low density, high melting temperature and cheap constituents make the alloy advantageous among other shape memory alloys. Although some magnetic properties of this alloy are known, there is no report on basic shape memory characteristics of CoNiAl. In this study, effect of thermo-mechanical treatments on the microstructure and shape memory characteristics such as transformation behavior, pseudoelasticity, stages of transformation, temperature dependence of the pseudoelasticity, response to thermal and stress cycling is investigated. Formation of second phase along the grain boundaries and inside the grains, about 4% pseudoelastic and two-way shape memory strain, very narrow stress hysteresis, large pseudoelastic window (>150°C), two-stage martensitic transformation, stable response to cyclic deformation, high strength for dislocation slip, slope of Clasius-Clapeyron curve, and twinning plane are determined for the first time in literature.

A Newton-Krylov algorithm is presented for aerodynamic shape optimization in three dimensions using the Euler equations. An inexact-Newton method is used in the flow solver, a discrete-adjoint method to compute the gradient, and the quasi-Newton optimizer to find the optimum. A Krylov subspace method with approximate-Schur preconditioning is used to solve both the flow equation and the adjoint equation. Basis spline surfaces are used to parameterize the geometry, and a fast algebraic algorithm is used for grid movement. Accurate discrete-adjoint gradients can be obtained in approximately one-fourth the time required for a converged flow solution. Single- and multi-point lift-constrained drag minimization optimization cases are presented for wing design at transonic speeds. In all cases, the optimizer is able to efficiently decrease the objective function and gradient for problems with hundreds of design variables.

A Newton-Krylov algorithm is presented for aerodynamic shape optimization in three dimensions using the Euler equations. An inexact-Newton method is used in the flow solver, a discrete-adjoint method to compute the gradient, and the quasi-Newton optimizer to find the optimum. A Krylov subspace method with approximate-Schur preconditioning is used to solve both the flow equation and the adjoint equation. Basis spline surfaces are used to parameterize the geometry, and a fast algebraic algorithm is used for grid movement. Accurate discrete-adjoint gradients can be obtained in approximately one-fourth the time required for a converged flow solution. Single- and multi-point lift-constrained drag minimization optimization cases are presented for wing design at transonic speeds. In all cases, the optimizer is able to efficiently decrease the objective function and gradient for problems with hundreds of design variables.

Spinal needle injections for back pain management are frequently carried out in hospitals and radiological clinics. Currently, these procedures are performed under fluoroscopy or CT guidance in specialized interventional radiology facilities. As an alternative, the use of inexpensive ultrasound image guidance promises to improve the efficacy and safety of these procedures. We propose to eliminate or reduce the need for ionizing radiation, by creating and registering a statistical shape model of the lumbar vertebrae to 3D ultrasound volumes of patient, using a groupwise registration algorithm. From a total of 35 patient CT volumes, a statistical shape model of the L2, L3 and L4 vertebrae is built, including the mean shape, and principal modes of variation. The statistical shape model is registered to the 3D ultrasound by interchangeably optimizing the model parameters and their relative poses. We also use a biomechanical model to constrain the relative motion of the models throughout the registration process. Validation is performed on three tissue mimicking-phantoms designed to preserve realistic curvature of the spine. We compare pairwise and groupwise registration of the statistical shape model of the spine and demonstrate that clinically acceptable mean target error registration of 2.4 mm can be achieved with the proposed method. Registration results also show that the groupwise registration outperforms the pairwise in terms of success rate. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2010-09-27 20:08:01.828

The absorption of the energy in the form of heat from electromagnetic radiation is strongly dependent on the shape of the surface. Also, the transfer of this generated thermal energy is dependent on the surface area of the object in contact with the surrounding medium. Here in this thesis, we present a structural optimization method for metal nanostructures based on the shape dependency of their electromagnetic heat dissipation and thermodynamic transfer to the surroundings. We have used a parallel genetic algorithm (GA) in conjunction with a coupled electromagnetic (FDTD) and thermodynamic modeling of the metallic nanostructures for the optimization. The optimized nano-structure demonstrates significant improvement in electromagnetic heating in the spectral window of optimization as well as expedited cooling properties. The symmetry of the structures which is inherent in the design procedure makes them independent of the polarization at normal incidence and insensitive to the azimuthal direction of incidence.

The absorption of the energy in the form of heat from electromagnetic radiation is strongly dependent on the shape of the surface. Also, the transfer of this generated thermal energy is dependent on the surface area of the object in contact with the surrounding medium. Here in this thesis, we present a structural optimization method for metal nanostructures based on the shape dependency of their electromagnetic heat dissipation and thermodynamic transfer to the surroundings. We have used a parallel genetic algorithm (GA) in conjunction with a coupled electromagnetic (FDTD) and thermodynamic modeling of the metallic nanostructures for the optimization. The optimized nano-structure demonstrates significant improvement in electromagnetic heating in the spectral window of optimization as well as expedited cooling properties. The symmetry of the structures which is inherent in the design procedure makes them independent of the polarization at normal incidence and insensitive to the azimuthal direction of incidence.

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