Pollution levels in urban areas continue to rise, with transportation being the number one cause. As cities ban fossil fuel cars access to the city center, this project looks at the delivery of packgaes from internet purchases. A three-wheeled, human-powered and electrically assisted vehicle is designed. This vehicle is dsigned to work together with last-mile logistics. A scientific design process was carried out to define the stakeholders, competition and requirements of the project, among others.The results yielded a semi-finished vehicle, comprising of the frame, general design, FEA analysis, delivery system and an optimization process for the frame. Future work includes economical or social study, design of the brakes and gear system or a design of the frame-cabin connection.

<p>In an advanced avionics system, the demand of high reliability and availability is of great importance. Testability Analysis is a method of examining this. In the project RWE Tornado GE at Saab Avitronics, they use Built-In Test (BIT), for the purpose of detecting and isolating possible failures in the equipment in question. There is however the need of verification of BIT functionality. Some of the verification tests are requested by customer EADS to be simulated and demonstrated. The objective of this thesis is to understand the Testability Analysis process as well as develop a tool to assist the Testability Demonstration preparations and result recording.</p> / <p>Kravet på hög tillförlitlighet samt tillgänglighet är av yttersta vikt inom ett avancerat avioniksystem. Testbarhetsanalys är en undersökningsmetod som man kan tillämpa. I projektet RWE Tornado GE på Saab Avitronics använder man sig av inbyggda tester - Built-In Test (BIT) - för att kunna upptäcka och isolera eventuella felmoder i en utrustning. Utöver detta vill man verifiera att BIT-funktionen faktiskt fungerar. Vissa av dessa verifieringstester måste simuleras och demonstreras i enlighet med kunden EADS begäran. Målet med examensarbetet är att förstå testbarhetsanalysprocessen samt utveckla ett verktyg för att kunna göra nödvändiga förberedelser för samt resultatinsamling under testbarhetsdemonstrationen (T-Demo).</p>

Over the past century, the automobile has become an integral part of society, with vastincreases in safety, refinement, and complexity, but most unfortunately in mass. Thetrend of increasing mass cannot be maintained in the face of increasingly stringentregulations on fuel consumption and emissions.The body of work within this thesis exists to help the vehicle industry to take a stepforward in producing vehicles for the future in a sustainable manner in terms of botheconomic and ecological costs. In particular, the fundamentally conflicting requirementsof low weight and high stiffness in a structure which should have good acousticperformance is addressed.An iterative five step design method based on the concepts of multifunctionality andmultidisciplinary engineering is proposed to address the problem, and explained witha case study.In the first step of the process, the necessary functional requirements of the systemare evaluated. Focus is placed on the overall system behavior and diverted from subproblems.For the case study presented, the functional requirements included: structuralstiffness for various loading scenarios, mass efficiency, acoustic absorption, vibrationaldamping, protecting from the elements, durability of the external surfaces,and elements of styling.In the second step of the process, the performance requirements of the system wereestablished. This involved a thorough literature survey to establish the state of theart, a rigorous testing program, and an assessment of numerical models and tools toevaluate the performance metrics.In the third step of the process, a concept to fulfil requirements is proposed. Here, amulti-layered, multi-functional panel using composite materials, and polymer foamswith varying structural and acoustic properties was proposed.In the fourth step of the process, a method of refinement of the concept is proposed.Numerical tools and parameterized models were used to optimize the three dimensionaltopology of the panel,material properties, and dimensions of the layers in a stepwisemanner to simultaneously address the structural and acoustic performance.In the fifth and final step of the process, the final result and effectiveness of the methodused to achieve it is examined. Both the tools used and the final result in itself shouldbe examined. In the case study the process is repeated several times with increasingdegrees of complexity and success in achieving the overall design objectives.In addition to the design method, the concept of a multifunctional body panel is definedand developed and a considerable body of knowledge and understanding is presented.Variations in core topology, materials used, stacking sequence of layers, effects ofperforations, and air gaps within the structure are examined and their effects on performanceare explored and discussed. The concept shows promise in reducing vehicleweight while maintaining the structural and acoustic performance necessary in the contextof sustainable vehicle development. / QC 20110311

Variable compression engines are a mean to meet the demand on lower fuel consumption. A high compression ratio results in high engine efficiency, but also increases the knock tendency. On conventional engines with fixed compression ratio, knock is avoided by retarding the ignition angle. The variable compression engine offers an extra dimension in knock control, since both ignition angle and compression ratio can be adjusted. The central question is thus for what combination of compression ratio and ignition angle the maximum efficiency is achieved, considering the set of compression ratios and ignition angles that give a sufficiently low knock intensity. Four knock detection methods are proposed, compared and evaluated with respect to robustness for noise and choices of parameter values. Three of the knock detectors are categorised as on-line, and are designed for giving feedback about knock occurrence to the engine control unit. The methods can determine both whether or not knock is present and the crank angle at knock onset. A study of the relationship between knock oscillation properties and knock-onset is performed. It is concluded that the logarithm of the normalised knock energy depends almost linearly on the rate of knock occurrence. A new formulation of multi-zone engine models is presented. The formulation makes it easy to increase or decrease the number of zones during the simulation. One of many possible applications is the investigation of engine efficiency. An analysis of experimental data shows how the engine efficiency changes with compression ratio and ignition angle. An engine torque model is developed and validated, from which the optimal choice of compression ratio and ignition angle can be calculated with high accuracy.

In an advanced avionics system, the demand of high reliability and availability is of great importance. Testability Analysis is a method of examining this. In the project RWE Tornado GE at Saab Avitronics, they use Built-In Test (BIT), for the purpose of detecting and isolating possible failures in the equipment in question. There is however the need of verification of BIT functionality. Some of the verification tests are requested by customer EADS to be simulated and demonstrated. The objective of this thesis is to understand the Testability Analysis process as well as develop a tool to assist the Testability Demonstration preparations and result recording. / Kravet på hög tillförlitlighet samt tillgänglighet är av yttersta vikt inom ett avancerat avioniksystem. Testbarhetsanalys är en undersökningsmetod som man kan tillämpa. I projektet RWE Tornado GE på Saab Avitronics använder man sig av inbyggda tester - Built-In Test (BIT) - för att kunna upptäcka och isolera eventuella felmoder i en utrustning. Utöver detta vill man verifiera att BIT-funktionen faktiskt fungerar. Vissa av dessa verifieringstester måste simuleras och demonstreras i enlighet med kunden EADS begäran. Målet med examensarbetet är att förstå testbarhetsanalysprocessen samt utveckla ett verktyg för att kunna göra nödvändiga förberedelser för samt resultatinsamling under testbarhetsdemonstrationen (T-Demo).

<p>This thesis focuses on the use of multiple redundant control surfaces to increase performance during flight. There is no clear-cut definition of performance. It may differ between applications, but here, the amount of drag for a given flight condition is used. The work is concentrated on minimizing drag with the use of measurements instead of numerical simulations. Measured data contains noise and there are problems with repeatability and hysteresis. These difficulties are considered and a method for drag minimization during flight is presented.</p><p>In the first study the drag minimization algorithm is discussed. Focus is put on describing the implemented method and the treatment of constraints to the optimization problem. The constraints include keeping the lift constant as well as having bounds on the control surface deflections.</p><p>In the second work, a more complex wind tunnel model is used to validate the drag optimization algorithm. Drag reduction for different flight conditions is studied, as well as the impact of the number of control surfaces. Different layouts of the control surfaces are also tested. The results show that the constraints are satisfied and that the drag is reduced substantially.</p>

<p>The wheel loader is a type of engineering vehicle used primarily to move crude material over shorter distances. As the vehicle is designed without wheel suspension, wheel loader drivers are exposed to high levels of whole body vibration which influences ride comfort negatively. The work presented in this thesis has the aim to investigate the potential in adding an axle suspension to a wheel loader in order to reduce vibrations and increase handling quality. While suspended axles have great potential for improving ride comfort and performance, they will also necessarily affect the vehicle dynamic behaviour which is different in many aspects from that of passenger cars or other road vehicles: the wheel loader has a large pitch inertia compared to its mass, the axle loads vary considerably with loading condition, and the vehicle uses an articulated frame steering system rather than wheel steering. These issues must all be considered in the design process for a wheel loader suspension.</p><p>The effects of suspended axles on ride vibrations are analysed by simulating a multibody wheel loader model with and without axle suspension. Results from the simulations show that longitudinal and vertical acceleration levels are greatly reduced with axle suspension, but that the decrease in lateral acceleration is smaller. By reducing the roll stiffness lateral accelerations can be further reduced, although this may not be feasible because of requirements on handling stability. The pitching oscillation of the vehicle has also been studied as this is known to have a large influence on ride comfort. An analytical model is used to study the effect of front and rear suspension characteristics on the pitching response of the wheel loader, showing that a stiffer rear suspension is favourable for reducing pitching but also that a similar effect is attainable with a stiffer front suspension. Results are compared to multibody simulations which show the same trend as analytical predictions. By including a linearised representation of a hydropneumatic suspension in the models, it is also shown that favourable dynamic behaviour can be maintained when the vehicle is loaded by utilising the fact that suspension stiffness is increasing with axle load.</p><p>Articulated vehicles may exhibit lateral oscillations known as "snaking" when driven at high speed. The effect of suspended axles on these oscillations are analysed using a multibody simulation model of a wheel loader with an equivalent roll stiffness suspension model. It is found that the roll motion of the sprung mass has a slightly destabilising effect on the snaking oscillations. This effect is more pronounced if the body roll frequency is close to the frequency of the snaking motion, although this loss in stability can be compensated for by increasing the equivalent stiffness or damping of the steering system.</p><p>Together with existing vehicle dynamic theory and design rules, the studies reported in this work provide an insight into the specific issues related to suspension design for wheel loaders.</p>

Electric vehicle technology is an interdisciplinary field in continuous development. It appears to be a margin for improvements. The Division for Electricity at Uppsala University is doing significant research in the field. The present thesis investigates electric machines for vehicular applications, both in the driveline and in the traction motor. Section 1 presents a driveline with two galvanically isolated voltage levels. A low power side is operated at the optimum voltage of the batteries, while a high power side is operated at a higher voltage leading to higher efficiencies in the traction motor. Both sides are coupled through a flywheel that stabilizes the power transients inherent to a drive cycle. A review of electric machine topologies for electric vehicles is presented in Section 2. The permanent magnet excited machine is the most suitable technology for an electric driveline. Section 3 is devoted to numerical models applied to electric machines. The equivalent circuit of a motor/generator with two sets of windings is first presented. This machine couples both sides of the driveline and drives the rotor of the flywheel. The electric parameters are calculated with custom FEM models. A discussion on slotless machines concludes with a simple model to analyze the magnetic field from one static 3D simulation. The tooth ripple losses in solid salient poles are also analyzed with a novel FEM approach. A complete description of the losses in electric machines gives a proper background for further discussion on efficiency. Section 4 presents the experimental work constructed to validate the theoretical models. The experiments include an axial flux, single wounded prototype, an axial flux, double wound prototype and a planed radial flux coreless prototype. Section 5 focuses on traction motors for electric vehicles. A simulated prototype illustrates a design and calculation process. The loss theory and the numerical methods presented in Section 3 are applied.

Sammanfattning   På lastbilsmodellerna FH och FM från Volvo, finns det vibrationsdämpare mellan karossen och frontluckan. Dessa dämpar rörelse vid en hård stängning av luckan, förhindrar att luckan ock dörren kolliderar.  De nuvarande vibrationsdämparna går inte att justera på något vis, detta vill Volvo kunna göra, för att lättare kunna justera in frontluckans position mot dörren och få en bra inpassning som ger ett bra kvalitetsintryck för kunden. Flera koncept ska tas fram för att sedan jämföras med varandra i en beslutsmatris. Arbetet utförs på Volvo GTT, konstruktionsavdelning av Volvo GTO, i Umeå.   Viktiga avgränsningar: Endast framtagning av koncept, inte någon produktion av delarna. Inga hållfasthetsberäkningar av mig eller FEM-analys. Använda mig av programvaran CATIA V5 för CAD   Vad som utförts: Marknadsundersökning har utförts mot konkurrenter och tidigare koncept framtagna av Volvo, sedan framtagning av olika koncept för vibrationsdämpare med justering i CATIA v5. De koncept som tagits fram jämförs sedan i en Pugh-matris, viktiga egenskaper som pris, tillverkningsbarhet, monteringsbarhet jämförs med den nuvarande dämparen.   Resultat av Pugh-matrisen: Koncept 2 och 4 var bäst i denna analys, båda fick lika mycket poäng i sin jämförelse, dock utfördes analysen utan en kostnadsberäkning.   Diskussion och Slutsats: Två av koncepten är bättre lämpade att fortsätta utveckla, koncept 2 och 4, detta av både kostnadsskäl samt att de kan ändras för att ge en tillräcklig justering. Koncept 1 kan användas ett kortare tag, då det löser vissa problem som de har haft vid montering. Slutsatsen är att det går att göra olika koncept med justering för vibrationsdämpare. Den svåra delen att lösa är hur man ska kunna justera dämparna med stängd frontlucka. / Vibration-dampeners for front lid FH/FM   Concepts for vibration-dampers with adjustment   Joakim Kerwien   Abstract   The model-lines FH and FM from Volvo Trucks, have vibration dampers in the front of the cab.  These dampen the front lid and reduces the risk for the front lid to slam into the door. The current vibration damper design is not position adjustable, which is something Volvo wants to have. This makes it easier to adjust the front lid, and get a good gap- and flush-positioning of the front lid, that gives an excellent quality impression for the customer. Several concepts are to be developed, which will be compared to each other in a decision matrix. The work is carried out at Volvo GTT, the design engineering branch of Volvo GTO in Umeå.   Important delimitations: Development of concepts, no production of parts yet. No strength of materials-calculations or FEM-analysis by me. Use CATIA v5 for CAD-purposes.   Work done: Market research has been done, towards rival companies, also researched some former concepts developed by Volvo employees, then I have made some different vibration dampers with adjustability in CATIA v5. The concepts developed were then put into a Pugh-matrix, where important attributes and qualities like price, manufacturability, difficulty of assembly were compared with the current damper.   Results of the Pugh-matrix: Concepts 2 and 4 were best in this analysis, both got the same amount of points, although this was without any cost analysis involved.   Discussions and Conclusions: Two of the concepts are better suited for further development, concepts 2 and 4, both from cost reasons, also they both have adequate adjustability. The conclusion is that it is feasible to make different concepts for vibration-dampers with adjustability. The hard part to solve is how you can adjust the dampeners with the front lid closed.

During the past years, several tools have been developed to try predicting wheel and rail wear of railway vehicles in an e-cient way. In this MSc thesis a new wear prediction tool developed by I.Persson is studied and compared with another wear prediction tool, developed by T.Jendel, which has been already validated and is in use since several years ago. The advantages that the new model gives are simpler structure, the consideration of wear as a continuous variable and that all the code is integrated in the same software. The two models have the same methodology until the part of the wear calculations and the post-processing. Wheel-rail geometry functions and time domain simulations are performed with the software GENSYS. In the simulation model the track and the vehicle are dened as well as other important properties such as vehicle speed and coe-cient of friction. Three simple tracks are used: tangent track, R=500 m curve with a cant of ht=0.15 m on the outer rail and R=1000 m curve with a cant of ht=0.1 m on the outer rail. The model is assumed to be symmetric so just outer (first and fourth axle) and inner (second and third axles) wheels are considered. During the vehicle-track interaction, the normal and tangential problems are solved. The wheel-rail contact is modelled according to Hertz's theory and Kalker's simplied theory with the help of the algorithm FASTSIM. Then wear calculations are performed according to Archard's wear law. It is applied in dierent ways, obtaining wear depth directly in Jendel's and wear volume rate in Persson's model. Jendel's model is rstly analyzed. Its specifc methodology is briefly explained and modications are performed on the code to make it work as similar as possible to Persson's model. Also parameters regarding the distance in which wear calculations are taken, the discretization of the width of the wheel and the discretization of the contact patch are analyzed. The methodology of Persson's model is also studied, most of all the performance of the post-processing which is one of the keys to the code. The parameters analyzed in this code are the ones regarding a statistical analysis performed during the post-processing and the discretization of the contact patch. Finally the comparisons between the wear depth obtained for both models are carried out. The discrepancies between the models are explained with the parameters analyzed and the dynamic behaviour of both models. Also a theoretical case is used as reference for comparison.