The aim of this thesis is to create a design rear upright for a racing Formula Student category car. It is necessary to propose a design group of the rear wheel assembly with the upright with all requirements related thereto, for example solutions camber settings. Everything is modeled using the CAD system. There is developed computational model which is placed in ballast states of strain and stress analysis by finite element method. There is also designed a suitable material for the production of the rear upright which is optimized. The conclusion deals with the inclusion of the proposed arrangement in the overall vehicle assembly and is concluded with evaluation and suitability of the proposed solution.

A wind tunnel based investigation into the effects of unsteady yaw angles on the aerodynamics of a simple automotive body has been carried out to increase the understanding of the effects of unsteady onset conditions similar to those experienced in normal driving conditions. Detailed flow field measurements have been made using surface pressure tappings and PIV around a simple automotive model in steady state conditions and these have been compared to measurements made whilst the model was oscillating in the yaw plane. The oscillating motion was created by a motored crank which was used to produce consistent and repeated motion which produced a reduced frequency that indicated that a quasi-static response should be expected. The PIV data are used to compare the wake flow structures and the surface pressures are used to infer aerodynamic loads and investigate the development of the flow structures across the surfaces of the model. This includes a comprehensive comparison of the surface pressures on the sides of the model during a transient and quasi-static yaw angel oscillation. These results show differences between the two test conditions with the oscillating model results containing hysteresis and the greatest differences in the flow field occurring on the leeside of the model. Two configurations of the same model with different rear pillar geometries were used to isolate model specific effects. Square rear pillars create strong and stable trailing vortices which are less affected by the model motion whereas radiused rear pillars created weaker and less steady vortices that mixed with the quasi-2D wake behind the model base and were affected to a greater extent by the model motion. The unsteadiness in the trailing vortex separation feeds upstream into the A-pillar vortex demonstrating that small geometry changes at the rear can affect the entire flow field around the model.

L'objectif d'amélioration des performances de cellules solaires sur des substrats de silicium cristallin de plus en plus en minces (< 200 µm) est indispensable à la réduction des coûts du module et donc à l'essor du photovoltaïque à l'échelle mondiale. Cette thèse se propose de répondre à la problématique d'amincissement des plaquettes sur substrats monocristallins (Cz) de type p de grande surface (239 cm2 - 180 µm) par le développement d'une structure en face arrière capable de générer un rendement de conversion élevé tout en limitant le degré de complexité du procédé de fabrication de la cellule. La solution explorée est celle des cellules à face arrière passivée et contacts localisés et les schémas de passivation étudiés s'appuient sur l'utilisation d'empilements diélectriques à base d'oxydes de silicium (SiO2) et d'aluminium (Al2O3) couplés au nitrure de silicium (SiNx). Ces travaux ont pour objectif d'optimiser les propriétés de passivation des couches diélectriques tout autant que les briques technologiques nécessaires à leur intégration dans la structure de cellule finale (conditionnement de surface, ablation laser sélective, métallisation par sérigraphie). Le procédé de fabrication résultant a permis d'obtenir des cellules avec un rendement de conversion de 19.1% pour l'empilement SiO2/SiNx. Il est cependant démontré que les limitations des performances de cette structure peuvent être partiellement compensées en introduisant une couche d'alumine, permettant d'atteindre un rendement remarquable de 19.5% (+0.4% par rapport à une structure standard). / Improving the solar cell efficiency on thin wafers (< 200 µm) has become a must in the industry in order to reduce the module cost and enhance the photovoltaics field growth worldwide. This work addresses the issues regarding the thickness reduction of large monocrystalline p-type wafers (239 cm2 - 180 µm) by developing a back side architecture capable of increasing the efficiency while limiting the cell fabrication level of complexity. Thus back passivated and local contacts, also known as PERC-type, solar cells are investigated. Those include passivation schemes relying on the use of dielectric stacks based on silicon oxide (SiO2), aluminum oxide (Al2O3) both coupled with silicon nitride layers (SiNx). This PhD study attempts to carry out an optimization of the passivation properties as well as of the technological steps required for a proper integration in the final cell structure (surface preparation, selective laser ablation, screen-printing metallization). The resulting optimized process led to the fabrication of solar cells displaying an 19.1% conversion efficiency by using SiO2/SiNx layers. Nevertheless it was shown evidence that the limited electrical performances can be overcome by introducing an Al2O3 layer, eventually reaching a remarkable 19.5% efficiency. This represents an absolute gain efficiency of +0.4% compared to the standard full-area Al-BSF solar cell architecture.

Background: The latest generation of rear-end whiplash protection systems, as found in the WHIPS Volvo and SAHR Saab, have reduced injury rates by almost 50% in comparison with the previous generation of seat/head restraint systems. Occupant behaviour, such as seated posture and seat adjustment settings, may affect the injury risk. Method: Five studies were conducted. Studie I was an injury outcome study based on insurance data. Studies II-IV investigated seat adjustment, occupant backset, and cervical retraction for drivers and occupants in different postures and positions in the car, during stationary and driving conditions. Study V compared the occupant data from studies II and III with a vehicle testing tool, the BioRID dummy, using the protocols of the ISO, RCAR, and the RCAR-IIWPG. Results: Female drivers and passengers had a threefold increased risk for medically-impairing neck injury in rear-end impacts, compared to males. Driver position had a double risk compared with front passenger seat position. Female drivers adjusted the driver seat differently to male drivers; they sat higher and closer to the steering wheel and with more upright back support. The volunteers also adjusted their seat differently to the ISO, RCAR, and RCAR-IIWPG protocol settings; both sexes sat further away from the steering wheel, and seat back angle was more upright then in the protocols. In stationary cars, backset was highest in the rear seat position and lowest in the front passenger seat position. Males had a larger backset than females. Cervical retraction decreased and backset increased for both sexes when posture changed from self-selected posture to a slouched posture. The BioRID II dummy was found to represent 96th percentile female in stature, and a 69th percentile female in weight in the volunteer group. Conclusions: Risks in car rear-end impacts differ by sex and seated position. This thesis indicates the need for a 50th percentile female BioRID dummy and re-evaluation of the ISO, RCAR, and RCAR-IIWPG protocols, and further development of new safety systems to protect occupants in rear-end impacts.

This thesis proposes and demonstrates a hydrogenated amorphous silicon passivated, inverted photovoltaic device on n-type silicon, utilizing a Laser Fired Emitter on a rear i-a- Si:H/SiOx dielectric stack. This novel low-temperature-fabricated device architecture constitutes the first demonstration of an LFE on a dielectric passivation stack. The optimization of the device is explored through Sentaurus computational modeling, predicting a potential efficiency of >20%. Proof of concept devices are fabricated using the DC Saddle Field PECVD system for the deposition of hydrogenated amorphous silicon passivation layers. Laser parameters are explored highlighting pulse energy density as a key performance determining factor. Annealing of devices in nitrogen atmosphere shows performance improvements albeit that the maximum annealing temperature is limited by the thermal stability of the passivation. A proof of concept device efficiency of 11.1% is realized forming the basis for further device optimization.

This thesis proposes and demonstrates a hydrogenated amorphous silicon passivated, inverted photovoltaic device on n-type silicon, utilizing a Laser Fired Emitter on a rear i-a- Si:H/SiOx dielectric stack. This novel low-temperature-fabricated device architecture constitutes the first demonstration of an LFE on a dielectric passivation stack. The optimization of the device is explored through Sentaurus computational modeling, predicting a potential efficiency of >20%. Proof of concept devices are fabricated using the DC Saddle Field PECVD system for the deposition of hydrogenated amorphous silicon passivation layers. Laser parameters are explored highlighting pulse energy density as a key performance determining factor. Annealing of devices in nitrogen atmosphere shows performance improvements albeit that the maximum annealing temperature is limited by the thermal stability of the passivation. A proof of concept device efficiency of 11.1% is realized forming the basis for further device optimization.

Rapporten beskriver förslag på framtidens ”Rear Seat Entertainment” som baseras på användning av pekskärm, istället för de DVD-baserade TV-skärmar som finns i t ex Volvo S80 i dagsläget. Projektet utfördes som ett examensarbete inom integrerad produktutveckling vid Högskolan i Skövde. Syftet med arbetet var att hitta lösningar som möjliggör användning av ”touchteknik” som kräver armavstånd till displayen. Arbetet delades upp i tre delar där val av pekskärmsenhet (inbyggd eller mobil), positionering av pekskärmen i bilen enligt ergonomiska rekommendationer, samt anpassning för olika stora personer inkluderade barn och utformning av infästningselement har utvecklats.  Arbete inleddes med litteraturstudier om interaktion av pekbaserade interface, målgruppsundersökningar, sammanställning av marknadsundersökningar, trendanalyser samt ergonomiska förutsättningar och miljöutvärderingar.  För idégenereringen användes kreativa och systematiserade metoder. Urval av idéer skedde i samråd med Volvo och med hjälp av en konceptvalsmatris. Det  slutliga  konceptet  baseras  på  användningen  av  mobila  pekskärmsenheter.  Dessa  motsvarar  bäst  de  i dagsläget ställda kriterierna på användning, ekonomi, miljö och flexibilitet. Dessutom erhålls en enklare mjuk- och hårdvaruuppdatering.   Positionering  av  pekskärmar  i  bilens  baksäte  gjordes  med  hjälp  av  ergonomiska  rekommendationer  samt databaserade beräkningar och simuleringar.    Utformning av infästningselementen anpassades till kravspecifikationen och resulterade i ett fäste som håller fast enheten med hjälp av  permanentmagneter  som byggs in i  ett infästningselement  på stolens baksida och ett i fodralet för surfplattan. Arbetet har lett till skärmar som enkelt kan fästas med magnetkrafter.

Front projection is an economical method to produce large displays. However, the twin problems of occlusions, which create shadows on the screen, and light projected onto users near the screen, potentially blinding them, makes front projection a poor fit for large upright interactive surfaces. Virtual Rear Projection (VRP) uses multiple redundant front projectors to provide the user experience of using a rear projected display. By using a projector-camera system to mitigate shadows and blinding light, a virtual rear projected display significantly improves upon the user experience of a traditional front projected display, allowing it to replace a rear projected display. In this thesis we characterize the problems caused by shadows and occlusions and develop projection technologies that mitigate shadows and blinding light. We also present a laboratory performance evaluation, and a user evaluation of the technology showing that VRP improves the user experience with respect to traditional front projection.

Whiplash injuries as a result of rear impact are among the most common injuries in traffic accidents. This is why whiplash injuries have reached a high priority in the research area. In this study, the effects of head restraint position and impact pulse to the whiplash injury have been analyzed by performing whiplash tests using the sled test facility of METU-BILTIR Center Vehicle Safety Unit. Although there are many whiplash test protocols, the test sample has been prepared according to the most recent one, Euro NCAP Whiplash Test Protocol. Three different head restraint positions and three different impact pulses with different severities, totally nine tests have been performed. The tests are performed with a three point generic seat belt and an instrumented Hybrid III 50th percentile male adult crash test dummy is used as the occupant in driver seat of a light commercial vehicle. High speed cameras, sensors on the crash test dummy and a data acquisition system are used to take the test data. This test data has been analyzed and presented according to the defined whiplash assessment criteria and the performance scores of the particular seat for each test have been determined using the whiplash assessment criteria values according to the Euro NCAP Test Protocols.

<p>The automotive field is becoming more and more complex and cars are no longer just pure mechanical artifacts. Today much more than 50 % of the functionality of a car is computerized, so, a modern car system is obviously based on mixed technologies which emphasize the need for new approaches to the design process compared to the processes of yesterday. A corresponding technology shift has been experienced in the aerospace industry starting in the late sixties and today aircraft could not fly without its computers and the pilots’ environment has turned to a so called glass cockpit with no iron-made instrumentation left. A very similar change is still going on in the automotive area.</p><p>Simulator-Based Design (SBD) refers to design, development and testing new products, systems and applications which include an operator in their operation. Simulator-Based Design has been used for decades in the aviation industry. It has been a common process in this field. SBD may be considered as a more specific application of simulation-based design, where the specific feature is a platform, the simulator itself. The simulator could consist of a generic computer environment in combination with dedicated hardware components, for instance a cockpit. This solution gives us the possibility of including the human operator in the simulation.</p><p>The name of the project is Simulator-Based Design in Practice. The purpose of this master thesis is to get a complete practice in how to use a human-in-the-loop simulator as a tool in design activities focusing on the automotive area. This application area may be seen as an example of systems where an operator is included in the operation and thus experience from the car application could be transferred to other areas like aviation or control rooms in the process industry.</p><p>During the performance of the project we have gone through the main parts of the SBD process. There are many steps to complete the whole cycle and many of them have iterative loops that connect these steps with the previous one. This process starts with a concept (product/system) and continues with a virtual prototyping stage followed by implementation, test design, human-in-the-loop simulation, data analysis, design synthesis and in the end a product/system decision. An iterative process approach makes the cycle flexible and goal oriented.</p><p>We have learnt how to use the simulator and how to perform the whole cycle of SBD. We first started getting familiar with the simulator and the ASim software and then we were trying to reduce the number of computers in the simulator and changing the network in order to find good optimization pf the computer power. The second step has been to implement a new application to the simulator. This new application is the rear mirror view and consists of a new LCD monitor and the rear view vision that must be seen in the new monitor. Finally we updated the cockpit to the new language program Action Script 3.0.</p><p>The information gathering consisted of the course Human-System interaction in the University, the introduction course to ASim software and the course of Action Script 3.0.</p>