The dokument was created with ZDT company cooperation and consists of two main parts. The first and also main part is handling construction and strength check issues of two-axis traktor trailer chassis Grand super. The second part contains design and strength check of rear protective device against small vehicle under passing. Strength check is performed in I-DEAS enviroment. The fixings are chassis frame assembly drawing, chassis frame welding assembly drawing and drawbar assembly drawing.

This thesis solves design of functional device that will be able to automatically positioning back view mirrors according to the positio of driver face. Measuring position of the face provides stereovision of two webacams. The device is based on a computer Raspberry Pi 2 with designed expansion board. The created prototype can follow set view int the mirror with accuracy up to 7 cm (horizontally up to 5cm) in level of rear corner of a car. The results of this project validate design of automatic positioning mirror and it can be basis for specific implementations of the device in car.

Sexual harassment has existed for several decades and is still present in many differentindustries in Sweden. As the metoo movement grew, the topic became increasingly moreknown and current. This qualitative study is based on how management and employees at astate agency perceive preventative work aimed towards counteracting and neutralizing sexualharassments; moreover, the study also investigated whether the metoo-movement hasinfluenced this kind of prevention work. To be able to answer the study's question, aqualitative method was used in the form of eight semi-structured interviews. Based on theempirical data collected, we see that the perception of the preventive work differed betweenmanagement and employees. We want to believe that metoo has contributed to noticeablechanges in the organizational world.Based on information collected during some interviews, it can be stated that the metoomovement has not had a significant contribution to any adjustments in the organizationsprevention work: however, information collected from other interviews points towards therebeing major changes made to prevention work.The significant changes we have observed are updated guidelines and policies, employeesurveys, workplace meetings, and an updated intranet. We believe that sexual harassment isstill a major problem at workplaces and that there is a high number hidden statistic. / Sexuella trakasserier har funnits i flera decennier och finns även i dagsläget inom mångaolika branscher i Sverige. Ämnet blev mycket högaktuellt i takt med metoo-rörelsen. Dennakvalitativa studie är baserad på vilken uppfattning ledningen respektive medarbetare har i enstatlig myndighet på det förebyggande arbetet mot sexuella trakasserier dessutom om metoofenomenet har haft en inverkan på detta arbete. För att kunna besvara studiens frågeställninghar vi i utgått från en kvalitativ metod i form av åtta semistrukturerade intervjuer. Utifrån deninsamlade empirin har vi kunnat läsa av att uppfattningen om det förebyggande arbetetskiljde sig åt mellan ledning och medarbetare. Vi vill lita på att metoo har bidragit tillmärkbara förändringar inom organisationsvärlden. Vid vissa intervjutillfällen har vi kunnatkonstatera att metoo-rörelsen inte bidragit till några särskilda justeringar i organisationensförebyggande arbetet medan vid andra tillfällen har vi fått veta att det skett störreförändringar. De påtagliga förändringar vi har beaktat är uppdaterade riktlinjer och policys,medarbetarenkäter, arbetsplatsträffar och uppdaterad intranät. Vi anser att sexuellatrakasserier fortfarande är en stor problematik på arbetsplatser som består av ett stortmörkertal.

Bifacial photovoltaic (PV) modules have greater energy yield than traditional monofacial modules because they convert front and rear incident irradiance to electrical energy. Single-axis tracking systems can further increase energy yield and reduce the levelized cost of energy by rotating the modules throughout the day. However, racking elements in tracking systems introduce both shade and reflections on the rear face, increasing irradiance nonuniformity and fostering further electrical mismatch that reduces module power. The impact of racking, particularly that of the torque tube which spans the middle of the rear collector surface, must be accurately quantified in energy yield predictions to increase stakeholder confidence, and hasten the adoption of tracked bifacial modules. Isolating the torque-tube-reflected irradiance incident on the modules is crucial for this work. This is achieved by implementing arbitrary two-dimensional (2D) irradiance sampling on a module under test in bifacial_radiance, a ray tracing bifacial PV model, and taking the difference in rear irradiance profiles for simulations with a reflective and an absorptive torque tube at each timestamp. We calculate the TT reflection for the central one-in-portrait (1P) and two-in-portrait (2P) modules on horizontal single-axis trackers over hourly timestamps in a typical meteorological year in Livermore, California, USA. We introduce the TT reflection 2D irradiance profiles as additional light sources in DUET to quantify the TT reflection's impact on irradiance, electrical mismatch, and energy yield, as well as an incidence angle modifier's impact on TT reflection. We analyze the TT reflection based on sun zenith and diffuse fraction to group consistent illumination conditions across the year. We identify that TT reflection reduces electrical mismatch by partially offsetting TT shading, and increases annual energy yield by 0.11% and 0.18% in our particular 1P and 2P systems. While the overall impact of TT reflection is greater in the 2P system due to direct beam light incident on the TT, the TT reflection's greatest instantaneous relative contribution to total energy yield is larger for the 1P system, at high diffuse fractions and sun zeniths. For future work, we recommend validating simulation results with and without TT reflection against experimental data. The simulation method used for isolating the TT reflection may also be repurposed to help inform new TT designs that minimize electrical mismatch. Finally, instead of relying on bifacial_radiance to isolate the TT reflection, we recommend incorporating the TT as a Lambertian reflective surface in 3D view factor models with detailed shading for further TT reflection simulations.

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In this thesis the requirements for a rear wheel steering mechanism aimed to be implementedon KTH:s Formula Student car were evaluated. The requirements were obtainedby using already known loads, an analysis of how the quickly the driver turns the steeringwheel during track driving from video material and the Formula Student rulebook whichthe car is designed after. After the requirements were produced a number of concepts wereproduced and evaluated against each other. The concept that was given the highest scorewas a rack and pinion concept with a rotary actuator which was developed further.The design was made by first selecting an actuator with a planetary gearbox that couldfulfill the speed and load requirements and afterwards with CAD a design that could beintegrated on the car was made. The concept weighed around 1,7 kg and was compatiblewith the requirements. / I detta arbete undersöktes kraven som ställs på ett bakhjulsstyrningssystem för implementering på KTH:s Formula Student bil. Kraven togs fram genom att använda redan kända laster, en analys av hur snabbt föraren svänger utifrån videomaterial samt regelboken som alla formulastudentbilar är konstruerade efter. Efter att kraven tagits fram utvärderades ett antal koncept där det bästa konceptet, kuggstångsmekanism med ett roterande ställdon utvecklades vidare. Prototypdesignen gjordes genom att först välja ett ställdon med planetväxellåda som skulle klara av kraven och därefter med hjälp av CAD skapa en integrerbar design. Det färdiga konceptet väger ca 1,7 kg och klarar alla ställda krav.

This master thesis report has studied several methods to improve the energy consumption of an electric vehicle equipped with two permanent magnet synchronous motors. Two driving torque distribution maps are developed based on efficiency map and load transfer, respectively. The drive torque distribution map based on the efficiency map shows up to 8.94% energy saving. Two regenerative braking strategies are designed and compared. Both strategies have pure regenerative brake at low decelerations and it is controlled by a modified acceleration pedal map. Strategy 1 does not add more regenerative braking when the brake pedal is pressed thus it is simpler while strategy 2 can blend in more motor torque. Rear axle steering is also studied in terms of contribution to energy consumption and an LQR controller is developed to control the vehicle with rear axle steering. / Denna rapport avhandlar ett examensarbete där flera metoder har studerats för att förbättra energikonsumptionen för ett elektriskt fordon med två permanentmagnetsynkrona motorer. Två fördelningskartor för drivande moment är framtagna baserat på effektivitetskartor och lastöverföring. Fördelningskartorna för drivande moment som är baserat på effektivitet visar upp till 8,94% energiminskning. Två olika regenerativa bromsstrategier är framtagna och jämförda. Båda strategierna har ren regeneration vid låga decelerationer och är reglerat genom modifierat gaspedalsmappning. Strategi 1 ger inte mer regeneration när bromspedalen trycks ned och är då enklare medans strategi 2 kan blanda in mer vridmoment från elmotorn. Bakaxelstyrning är också studerat i termer av dess bidrag till energikonsumption samt en LQR regulator är utvecklad för reglering av fordonets bakaxelstyrning.

This diploma thesis deals with the issue of the driver's view from the vehicle, respectively the measurement of the field of views and blind spots. This thesis takes into account the 360° view around the vehicle. The first part of the thesis is devoted to the theoretical outlook of the vehicle. The reader becomes acquainted with the progressive development of the 360° view in a vehicle, beginning with the past and leading up to the present enhancements in today's vehicles. The reader will also understand, the position and movement of the eyes in a vehicle, the detailed description of the direct forward look, and the indirect reverse look. Subsequently, the theoretical part is devoted to the methodology of visibility measurements according to the prescribed standards of SAE and EHK. The theoretical part concludes with a chapter explaining how the theory is used in the practical part of the thesis. The practical part is devoted to the design of the 360° views of the vehicle and the description of the methodology. Another element of the practical part is the measurement protocol. This section deals with all the calculations for the complete driver's view, which was shown as an example on one of the sixteen vehicles measured. The last chapter compares, evaluates and reviews the results of all measured 360° views and blind spots around the vehicle.

The goal of this thesis work is to evaluate and quantify the advantages and disadvantages of Active Rear Steering (ARS). The evaluation is carried out through Multi-Body System (MBS) simulations. An analytical model has been developed to better understand the basic dynamics of vehicles equipped with rear steering. In parallel, a high fidelity MBS model is developed in Simpack. This model includes suspension kinematics and compliance, allowing for detailed analyses of steering hardware performance. Next, different control strategies aiming at improving manoeuvrability, stability and agility are implemented in Simulink. In order to assess their effectiveness, the high fidelity model is utilised by running co-simulation with Simulink. Manoeuvrability is assessed through constant steer, constant radius and ramp steer manoeuvres. Stability is assessed through transient manoeuvres such as step steer and sine with dwell. Agility is assessed through step steer and frequency response. Ultimately, also a subjective assessment is carried out by means of Volvo Cars' dynamic driving simulator. The conclusion from the assessment is that the drivers feel the all wheel steered vehicle more stable during evasive manoeuvres. It is concluded that for manoeuvrability the minimum turning radius is reduced by 19 % at low velocity; this implies that the steering angle request is reduced at low velocity, while it is increased at high velocity. A slightly higher steering angle request at high velocity might be beneficial since the driver would be able to control the vehicle in a wider range of steering wheel angles. For agility the results are contradicting: on the one hand, according to the step steer rise time difference between lateral acceleration and yaw rate, the controlled vehicles are performing worse than the passive vehicle; on the other hand, according to the frequency response analysis, both the delays between steering input and yaw rate and between lateral acceleration and yaw rate are reduced up to respectively 75 % and 46 % for the considered frequency range. Finally, for stability, the yaw rate overshoot from a step steer can be reduced up to 65 % at high velocity and the sideslip angle can always be reduced. The vehicle equipped with ARS outperforms the passive vehicle in the sine with dwell manoeuvre. / Målet med detta examensarbete är att utvärdera och kvantifiera fördelarna och nackdelarna med Active Rear Steer (ARS) för Volvo Cars. Utvärderingen utförs genom Multi-Body System (MBS) simuleringar. En analytisk modell har utvecklats för att bättre förstå den grundläggande dynamiken i fordon utrustade med bakhjulsstyrning. Parallelt utvecklades en MBS-modell med hög precision i Simpack. Denna modell inkluderar hjulupphängningens kinematik och eftergivlighet, vilket möjliggör detaljerade analyser av styrhårdvarans prestanda. Därefter implementeras olika kontrollstrategier som syftar till att förbättra manövrerbarhet, stabilitet och agilitet i Simulink. För att bedöma deras effektivitet används MBS-modellen för att köra co-simulering med Simulink.Manövrerbarhet bedöms genom konstant styrning, konstant radie och rampstyrning. Stabilitet bedöms genom transienta manövrar som stegstyrning och sinus med fördröjning. Agilitet bedöms genom stegstyrning och frekvensrespons. Slutligen görs också en subjektiv bedömning med hjälp av Volvo Cars dynamiska körsimulator. Slutsatsen från bedömningen är att förarna anser att fordonet upplevs vara mycket stabilare vid undanmanövrar. Vidare är slutsatsen att för manövrerbarhet minskar den minsta svängradien med 19 % vid mycket låg hastighet; detta innebär att styrvinkel reduceras vid låg hastighet, medan den ökar vid hög hastighet. En något högre styrvinkeln kan vara fördelaktig eftersom föraren skulle kunna styra fordonet i ett större rattvinkelområde. För agilitet är resultaten motsägelsefulla: å ena sidan, enligt stegstyrningstidsskillnaden mellan lateral acceleration och girhastighet, fungerar de aktiva fordonen sämre än det passiva fordonet; å andra sidan, enligt frekvensresponsanalysen, reduceras både fördröjningarna mellan girhastighet och styrvinkel och mellan lateral acceleration och girhastighet upp till ungefär 30 %. Slutligen, för stabilitet, kan girhastighetens översläng från en stegstyrning minskas upp till 65 % vid hög hastighet och avdriftsvinkeln kan alltid minskas. Fordonet som är utrustat med ARS överträffar det passiva fordonet i manövern sinus med fördröjning.

Made available in DSpace on 2016-03-15T19:36:37Z (GMT). No. of bitstreams: 1 Kyosuke Siqueira Saito.pdf: 4273063 bytes, checksum: 72ef7d0c147daede5763573276e7efda (MD5) Previous issue date: 2013-02-15 / Universidade Presbiteriana Mackenzie / The development of new commercial vehicles have as one of its major goals increase the operational energetic efficiency or fuel consumption decrease. The vehicle´s mass reduction is one of the most direct ways to achieve this goal. The vehicle´s axles usually have its structure made of ferrous materials due to its high strength and low cost. Alternative materials with lower density and higher strength are continuosly researched and developed. Among these materials the aluminum compared with ferrous materials appears as an interesting alternative to replace ferrous alloys in some applications. The aluminum have its density significantly smaller than ferrous materials opening possibilities to significant mass reductions. In this study were performed an evaluation through the comparison of aluminum alloys and ferrous materials on different load conditions and were presented the replacement gains for each load situation. It was evaluated possibility to replace ferrous materials with aluminum alloys on commercial vehicles rear axle structures through finite element analysis as a step on a new product validation. The study results show that is possible to use the aluminum in commercial vehicle axles with mass reduction ranging from 1,1% to 61,0% without loss of structural properties. / O desenvolvimento de novos veículos comerciais tem como um de seus objetivos principais o aumento da eficiência energética operacional ou redução do consumo de combustível. A redução da massa dos veículos é uma das estratégias mais diretas para o alcance deste objetivo. Os eixos de veículos tradicionalmente têm sua estrutura feita de materiais ferrosos devido à sua alta resistência e baixo custo. Materiais alternativos de mais baixa densidade e alta resistência são pesquisados e desenvolvidos continuamente. Dentre esses materiais, o alumínio, comparado com materiais ferrosos tem-se mostrado uma alternativa interessante para a substituição de ligas ferrosas para algumas aplicações. O alumínio possui uma densidade muito inferior a dos ferrosos abrindo a possibilidade de ganhos significativos de massa. Neste estudo foi feito uma avaliação através da comparação entre ligas de alumínio e materiais ferrosos em diferentes condições de carregamento e apresentado os ganhos da substituição em cada condição de carregamento. Foi avaliada a possibilidade de substituir materiais ferrosos por ligas de alumínio na estrutura de eixos traseiros de veículos comerciais através de uma análise por elementos finitos como uma etapa da validação de um novo produto. Os resultados do estudo mostram que é possível usar o alumínio na estrutura de eixos de veículos comerciais com redução de massa variando de 1,1% a 61,0% sem perda de características estruturais.