Die Hupkraftverteilung eines airbagintegrierten Automobillenkrades wird mit Hilfe einer Parameterstudie in MathCAD so optimiert, das an jeder Krafteinleitungsposition die Hupe mit einer geforderten Mindestkraft betätigt werden kann. Nach der Modellierung in MathCAD der zugehörigen Geometrie und der Dimensionierung der Federlagerung ist das zugehörige mechanische Ersatzmodell mit Hilfe einer Parameterstudie verändert worden, so dass die Hupkraftforderung erfüllt wird.

Besides the braking system the steering system is one of the most important systems on vehicles. The reliability and the performance of a steering system decides on the controllability of the vehicle under normal conditions as well as emergency situations. In everyday use the characteristics, the connectivity to assistance systems and the energy efficiency of the steering system become more and more important to fulfill the increasing demands regarding fuel consumption, carbon dioxide emissions and comfort. To meet these demands, new steering systems must be implemented and new technologies have to be developed. This contribution compares different approaches regarding functionality and energy efficiency to give an indication which system is the most promising solution for future front axle steering systems as well as rear steered axles (tag- or pusher axle) on trucks.

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In recent years, multi-functional reconfigurable antennas (MRA) has attracted much attention in wireless communication. The reconfigurable antenna can adapt itself with changing system conditions, and it can provide different multi-functionalities which can give better system performances. Instead of using multiple antennas, a single reconfigurable antenna can provide the same performance and occupy less space. By using the parasitic layer technique, an antenna can be turned into a reconfigurable antenna. The main objective of this thesis is to study radiation pattern reconfiguration of the horn antenna by using the parasitic layer concept. The MRA consists of a single horn, dielectric loaded truncated pyramid (DLTP), and the parasitic layer. The antenna that is chosen in this thesis is the horn antenna because it provides high directivity. DLTP is used for magnification purpose. The results show that three modes of operations that provide better performances compared to the single horn antenna are achieved.

This qualitative study explores how crisis preparedness practitioners in Sweden perceive theAgreement on Municipalities' Crisis Preparedness and how the municipalities haveimplemented what is stated in the Agreement on Municipalities' Crisis Preparedness. Drawingon theories about soft governance and policy instruments this has allowed the study to explorehow the agreement might be viewed by those working with it in relation what the theories hasto say. This has been done through performing semi-structured interviews with seven crisispreparedness practitioners at seven different municipalities spread across Sweden. For thisstudy a thematic analysis was performed on the material, based on the interview guide and theindicators, Perception, and Implementation. The result of this study is that agreement is constructed in a way to give freedom to thoseworking with crisis preparedness and is seen as soft by practitioners, which means that theagreement as such can largely be seen as soft governance. However, some practitionersexpressed the notion that they would have liked to see clearer and stricter governmentalsteering. That it could be viewed as soft means that the agreement could potentially takeadvantage of the benefits to using a soft approach, or this would be the case if the studywasn’t able to show that there exist, a problem with crisis preparedness. This problem is thatthere is not enough money to do more than is necessary regarding crisis preparedness. Whythis is could be questioned as the municipalities have taxation rights and it could as such beinteresting to delve deeper into why this is in a future study.

I detta examensarbete undersöks yrkeshögskolans struktur genom en intervjustudie. I fokus ligger olika intressenters roll och påverkansmöjligheter i yrkeshögskolan, samt yrkeshögskolans koppling till näringslivet. Arbetet har för avsikt att besvara på vilket sätt ledningsgrupperna inom tekniska yrkeshögskoleutbildningar har möjlighet att påverka innehållet samt hur förutsättningarna för lärande ser ut inom utbildningarna.För att besvara detta har respondenter från en teknisk yrkeshögskoleutbildning intervjuats och dessa intervjuer har sedan analyserats med en tematisk analys. Diskussionen utgår från teori kring områdena intressentmodellen, organisationsidentitet, kunskap och kompetens, yrkesdidaktik och yrkesläraridentitet samt skolutveckling och skolledare.Det har framkommit i arbetet att arbetslivsrepresentanterna i ledningsgruppen har möjligheter att påverka utbildningarna eftersom de är en stark intressent till utbildningen. Denna möjlighet till påverkan på utbildningen påverkas i sin tur av närvaron på ledningsgruppsmötena. Angående förutsättningar för lärande har det visat sig att LIA-praktiken (lärande i arbete) är en viktig del av utbildningen samt att den pedagogiska kompetensen hos undervisande lärare ibland brister. / This master thesis explores the structure of the Swedish higher vocational education, by a study of interviews. The focus of this essay is the impact potential of the stakeholders in the higher vocational education, and the connection between the higher vocational education and the enterprise. This study intends to answer questions about the steering committees’ possibilities to affect the content of technical educations. It also intends to investigate the prerequisites for learning.To answer these questions respondents from a technical program of the higher vocational education have been interviewed. These interviews have then been analysed by a thematic analysis. The discussion starting from theories about stakeholder theory, organizational identity, knowledge and competence, vocational pedagogy and vocational teachers’ identity and school development and principals.It has appeared that the industry representatives in the steering committees have opportunities to affect the educations, due to that they are a strong stakeholder. This opportunity is affected by the presence during the meetings with the steering committee. Concerning the prerequisites for learning, it has been found that the ‘LIA-practice’ is an important part of the education and that the pedagogical competences of the teachers sometimes is insufficient.

This thesis report presents a study on the virtualization of an Electric Cabin Scooter used to validate the feasibility of converting it into an autonomous vehicle. The project aimed to design, develop, and test a virtual model of the car that can navigate from points A to B while avoiding obstacles. The report describes the methodology used in the project, which includes setting up the workspace, construction of the virtual model, implementation of ROS2 controllers, and integration of SLAM and Navigation2. The thesis report also describes and discusses related work, as well as the theoretical background of the project. Results show a successfully developed working virtual vehicle model, which provides a solid starting point for future work. / Detta examensarbete presenterar en studie om virtualiseringen av en elektrisk kabinscooter. Den virtuella modellen används för att validera genomförbarheten av att omvandla den till ett autonomt fordon. Projektet syftade till att designa, utveckla och testa en virtuell modell av bilen som kan navigera från punkt A till B medan den undviker hinder. Rapporten beskriver metodiken som används i projektet, vilket inkluderar att sätta upp arbetsytan, konstruktion av den virtuella modellen, implementering av ROS2-kontroller och integration av SLAM och Navigation2. Rapporten diskuterar även relaterat arbete, samt teoretisk bakgrund till arbetet. Resultaten visar en framgångsrikt utvecklad fungerande virtuell fordonsmodell, som ger en solid utgångspunkt för framtida arbete.

The full spatial covariance matrix of the multiple input multiple-output (MIMO) channel is an important quantity in channel modeling, communication system signal processing, and performance analysis, and therefore this matrix forms the heart of the research outlined in this dissertation. The work begins with an investigation of a generalized framework for computing the full MIMO spatial covariance based on the power angular spectrum (PAS) of the multipath field and the transmit and receive antenna element radiation patterns. For the case of uniform linear arrays and when the PAS clusters satisfy uniform, truncated Gaussian, or truncated Laplacian distributions, a series expansion is used to allow analytic evaluation of the required integrals in the formulation. The study also demonstrates the validity of some simplifying assumptions used to reduce the complexity of the covariance computation by applying the technique to ray tracing data as well as considers an analysis of the convergence properties of the series when computed using a finite number of terms. The insights and tools obtained from this covariance analysis are then used to develop a general approach for constructing MIMO transmit and receive beamforming vectors based on the full spatial covariance. While transmit and receive beamforming for the MIMO channel is a well-studied topic, when the transmit precoding is based on channel covariance information, developing near-optimal transmit and receive beamformers when the receiver is constrained to use linear processing remains an unsolved problem. This iterative beamforming algorithm presented here can accommodate different types of available channel information and receiver capabilities as well as either a sum power constraint or a per-antenna power constraint. While the latter is more realistic, construction of the optimal transmit precoder is less understood for this constraint. Simulation results based on measured channels demonstrate that the approach generates beamformer solutions whose performance rivals that achieved for an optimal nonlinear receiver architecture.

In today’s lighter vehicles, EPS has had smaller breakthroughs, but not in heavyduty due to its high initial cost and lack of research. Even though there ispotential in the future when trucks may go electric. In this report, the theoreticalrequirements to implement an EPS system will be determined and investigatedalong with an in depth analysis of the electrical motor and planetary gearbox used.A preferred EPS system will consist of a Permanent magnet electric motor and aplanetary gearbox with optimized characteristics regarding voltage, cost, shape,dimensions and layout. The results lead to a theoretical EPS system that can befitted into a heavy duty truck’s engine compartment. Problems with implementingEPS, such as cost, electrical issues and limited space as well as possibilities forfuture work are discussed.

Avhandlingen presenterar resultatet av ett examensarbete i maskindesign på KTH. Uppgiften utfördes för ABB AB, Corporate Research.ABB vill undersöka en ny drivlinjekonstruktion för lågkostnadsautomatisering. ABB Robotiks har begränsat utbud av produkter rörande mobila plattformar. Det finns en stor marknadspotential för samarbetsrobotar på mobila plattformar bland kunder med både låg och hög grad av automation.I denna rapport diskuteras en möjlig designlösning av drivlinan för en mobil robotplattform. Generellt är utformningen av en robust drivlina för mobilplattform en komplex uppgift eftersom inte alla arbetsförhållanden är lika i en industriell installation. Till exempel kan vissa industriområden för logistik och andra för tung teknik etc. Idag finns det mycket fa designer av mobila industriplattformar konstruerade för ojämn yta, ytor med sprickor, stötar och liknande ojämna egenskaper. Befintliga industriella lösningar är utformade för jämna ytor inom gränserna for golvdesignen och överensstämmer också med lasterna på plattformens drivlina. En robust lösning föreslås i denna rapport. Detta baseras på en litteraturöversikt med konstruktionsarbete inkluderande lättillgängliga billiga komponenter samt modellutvärdering för att klara specifikationen av grova golv ojämnheter. Studien för att implementera en stötdämpare baserad drivlinjemodul har också inkluderats för att undersöka möjligheten att ha ett sådant drivsystem. Andra funktioner inkluderar också en inbyggd styrenhet som gör den mer kompakt genom att minska ledningar runt plattformen. Prestanda utfördes i en simuleringsmiljö för att se stötdämparens beteende. Den slutliga konstruktionen versionen byggdes som prototyp för vidare utvärdering i test. / This thesis presents the result of a master thesis in Machine Design at KTH. The task was performed for ABB AB, Corporate Research.ABB wants to investigate in a new driveline designs for low cost automation. ABB robotics doesn’t have any products concerning mobility application. There is a huge market potential for collaborative robots on mobile platforms with customers with both low and high budget of automation.This report discusses one possible design solutions of the driveline for a mobile robot platform. Generally, designing a robust driveline for mobile platform is a complex task since not all working conditions are alike in an industrial setup. For instance, some industrial area might for logistics, some might be for heavy engineering, etc. Moreover, there aren’t industrial platforms designed for uneven surface, surfaces having cracks, bumps and similar uneven features. The ones which can cope unevenness are for extreme off-road military conditions. Existing industrial solutions are designed for even surfaces within limits and the floor design is also in accordance to the platform driveline. A robust solution is proposed here after conducting a literature review with solid evidence and evaluation for the same to sustain rough floor designs with readily available inexpensive components. Study for implementing a shock absorber-based driveline module has also been included within to look at a possibility to have such a drive system. Other features also include an on-board controller which reduces the hassle of wiring around the complete platform. The performance was conducted on a simulation environment to see the behaviour of the shock absorber. The final design was prototyped for further evaluation.