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Vehicular systems have become intensively sophisticated and their software content has increased swiftly in this era. While developing the vehicular software, the requirements which should be satisfied are more complex in comparison to other types of software. As vehicular systems interact with physical processes, the high reliability of the system is always demanded. This is making testing a difficult but necessary step in developing reliable systems. Due to the competition and customer demands companies tends to update the software systems of their products as often as possible. Such demands put increased pressure on making testing more efficient and cost-effective. Traditionally, software testing is performed manually and in an ad-hoc manner. Moreover, manual testing becomes costlier when software is updated often. Hence there is the need for using techniques which can complement such manual techniques.   Model-based testing (MBT) is a test automation technique which promises to increase reliability, understandability, and maintainability of test cases by the use of test models, automatic test generation and execution. MBT[WU1]  is the process of test generation from design models of the system requirements and functionality. There are studies in the literature showing initial results on the advantages of using MBT with some promising results. Such promises are inspiring companies to take an interest in adopting the MBT approach. This thesis aims to evaluate the use of MBT in industrial practice and investigates the automated testing approach and its applicability in the context of Volvo CE.   The results of this thesis show that structural and behavior models can be created based on functional architecture and requirements of a real subsystem provided by Volvo-CE. These models are generated in Conformiq Creator MBT tool. Test cases are generated using different model coverage criteria.  The results suggest that activity and structure diagrams, developed using MBT, are useful for describing the test specification of an accelerator pedal control function subsystem. The use of MBT results in less number of test cases compared to manual testing performed by industrial engineers for these subsystems. We showed that MBT can be used for system modelling and test case generation in the vehicular domain.  [WU1]MBT is the process of testing design models of the system requirements and functionality.

Projekt Long Range CAN är ett examensarbete utfört åt Electrum Automation AB. Det är ett företag som utvecklar elektronikprodukter till framförallt mobila maskiner. De flesta av deras produkter använder CAN-buss. De har bland annat produkter för trådlös radioöverföring av CAN-bussmeddelanden. De saknar däremot en liknande produkt för trådlös radioöverföring som klarar avstånd över 1 km. Projektet går ut på att ta fram en prototyp för en sådan produkt och utvärdera om det är lämpligt att använda trådlös CAN-buss över större avstånd. Projektet har tagit fram en produkt som kan kommunicera på mer än 1 km. Kvalité på enkelriktad datatrafik är över 99 % vid en hastighet som är över 0.5 av den teoretiskt maximala hastigheten (ungefär 10 meddelanden per sekund). Vid dubbelriktad trafik levereras över 93 % av CAN-meddelanden med en hastighet på 2 x 1 meddelande per sekund. Det europeiska regelverket begränsar radiokanalens tidsutnyttjande till mindre än 2 CAN-meddelanden per sekund. Slutsats när det gäller lämpligheten av långdistans-CAN, är att det är lämpligt för tillämpningar som inte kräver överföring av mer än ett meddelande per sekund. / Project Long Range CAN is a thesis project for the company Electrum Automation AB. Electrum Automation AB is a company which developes electronics mostly for machine equipment and vehicles. Most of their products involve CAN-bus. They have products for wireless radiotransfer of CAN-messages. They however lack a product which can handle ranges over 1 km. The goal of the project is to develop a prototype for long range CAN-message transfer. How suitable CAN-bus is longer distances will then be evaluated. The project have developed a product which can communicate over a distance of more than 1 km. The quality of one-way data traffic is over 99 %, at a data rate faster than 0.5 of the maximum theoretical data rate (about 10 messages per second). Two-way traffic delivers 93 % of the CAN-messages at a speed of 2 x 1 messages per second. European regulations on ”air time”, limits the use of the radio channel to less than 2 CAN-messages per second. The conclusion to be drawn is that long distance CAN-bus can be suitable, if the application doesn’t require more than one CAN-message per second.

I dagens informationssamhälle är begrepp som smarta städer och IoT (Internet of Things) heta ämnen. Alla möjliga apparater ska vara uppkopplade på nätet och dessa ska prata och kommunicera med varandra. För att visioner för smarta städer ska förverkligas ställs nya krav på flera befintliga teknologier och även nya tekniker utvecklas för att ersätta eller komplettera de gamla. Denna rapport fokuserar på att jämföra äldre tekniker med nya inom områden för positionering och trådlös kommunikation. För positionering jämförs traditionell GPS (Global Positioning System) med Wi-Fi-baserade tjänster och inom kommunikation jämförs GSM (Global System for Mobile communications) med Sigfox, som är speciellt utvecklat för IoT-applikationer. En mätutrustning konstrueras av elektronikmoduler och en smarttelefon för att samla in data från olika geografiska områden och miljöer. Från insamlade data kan resultat visa hur positioneringstjänster förhåller sig till varandra och hur täckning kan förväntas av kommunikationsteknikerna. En indikation ges också på hur energiförbrukning kan förväntas vid användandet av de olika teknikerna. Till sist ges slutsatser på hur kombinationer av teknologier kan användas och vilka för- och nackdelar som kommer med varje kombination. Detta för att underlätta vid komponentvalet i en produktutvecklingsfas. / In today's information society, concepts like smart cities and IoT (Internet of Things) are hot topics. All imaginable devices should be connected to the internet and "things" should communicate with each other. For smart city visions to be realized, new demands are put on several existing technologies, and new technologies are being developed to replace or supplement the old ones. This report focuses on comparing older technologies with new ones within the areas of positioning and wireless communication. Traditional GPS (Global Positioning System) is compared to Wi-Fi based services and GSM (Global System for Mobile communications) is set against the Sigfox network that is specially developed for IoT applications. A measuring device is constructed by electronics modules and a smartphone to collect data in different geographic areas and environments. From the collected data, results can show how positioning services relate to each other and how coverage can be expected by communication technologies. An indication is also given of how the energy consumption can be expected when using the different technologies. Finally, conclusions are given on how combinations of technologies can be used and what pros and cons arise with the selected combinations. This facilitates component selection in a product development phase.

In today’s system-on-chip (SoC) implementations, power consumption is a key performance specification. The proliferation of mobile communication devices and distributed wireless sensor networks has necessitated the development of power-efficient analog, radio-frequency (RF), and digital integrated circuits. The rapid scaling of CMOS technology nodes presents opportunities and challenges. Benefits accrue in terms of integration density and higher switching speeds for the digital logic. However, the concomitant reduction in supply voltage and reduced gain of transistors pose obstacles to the design of highperformance analog and mixed-signal circuits such as analog front-ends (AFEs) and data converters. To achieve high DC gain, multistage amplifiers are becoming necessary in AFEs and analog-to-digital converters (ADCs) implemented in the latest CMOS process nodes. This thesis includes the design of multistage amplifiers in 40 nm and 65 nm CMOS processes. An AFE for capacitive body-coupled communication is presented with transistor schematic level results in 40 nm CMOS. The AFE consists of a cascade of amplifiers to boost the received signal followed by a Schmitt trigger which provides digital signal levels at the output. Low noise and reduced power consumption are the important performance criteria for the AFE. A two-stage, single-ended amplifier incorporating indirect compensation using split-length transistors has been designed. The compensation technique does not require the nulling resistor used in traditional Miller compensation. The AFE consisting of a cascade of three amplifiers achieves 57.6 dB DC gain with an input-referred noise power spectral density (PSD) of 4.4 nV/<img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?%5Csmall%5Csqrt%7BHz%7D" /> while consuming 6.8 mW. Numerous compensation schemes have been proposed in the literature for multistage amplifiers. Most of these works investigate frequency compensation of amplifiers which drive large capacitive loads and require low unity-gain frequency. In this thesis, the frequency compensation schemes for high-speed, lowvoltage multistage CMOS amplifiers driving small capacitive loads have been investigated. Existing compensation schemes such as the nested Miller compensation with nulling resistor (NMCNR) and reversed nested indirect compensation (RNIC) have been applied to four-stage and three-stage amplifiers designed in 40 nm and 65 nm CMOS, respectively. The performance metrics used for comparing the different frequency compensation schemes are the unity gain  frequency, phase margin (PM), and total amount of compensation capacitance used. From transistor schematic simulation results, it is concluded that RNIC is more efficient than NMCNR. Successive approximation register (SAR) analog-to-digital converters (ADCs) are becoming increasingly popular in a wide range of applications due to their high power efficiency, design simplicity and scaling-friendly architecture. Singlechannel SAR ADCs have reached high resolutions with sampling rates exceeding 50 MS/s. Time-interleaved SAR ADCs have pushed beyond 1 GS/s with medium resolution. The generation and buffering of reference voltages is often not the focus of published works. For high-speed SAR ADCs, due to the sequential nature of the successive approximation algorithm, a high-frequency clock for the SAR logic is needed. As the digital-to-analog converter (DAC) output voltage needs to settle to the desired accuracy within half clock cycle period of the system clock, a speed limitation occurs due to imprecise DAC settling. The situation is exacerbated by parasitic inductance of bondwires and printed circuit board (PCB) traces especially when the reference voltages are supplied off-chip. In this thesis, a power efficient reference voltage buffer with small area has been implemented in 180 nm CMOS for a 10-bit 1 MS/s SAR ADC which is intended to be used in a fingerprint sensor. Since the reference voltage buffer is part of an industrial SoC, critical performance specifications such as fast settling, high power supply rejection ratio (PSRR), and low noise have to be satisfied under mismatch conditions and over the entire range of process, supply voltage and temperature (PVT) corners. A single-ended, current-mirror amplifier with cascodes has been designed to buffer the reference voltage. Performance of the buffer has been verified by exhaustive simulations on the post-layout extracted netlist. Finally, we describe the design of a 10-bit 50 MS/s SAR ADC in 65 nmCMOS with a high-speed, on-chip reference voltage buffer. In a SAR ADC, the capacitive array DAC is the most area-intensive block. Also a binary-weighted capacitor array has a large spread of capacitor values for moderate and high resolutions which leads to increased power consumption. In this work, a split binary-weighted capacitive array DAC has been used to reduce area and power consumption. The proposed ADC has bootstrapped sampling switches which meet 10-bit linearity over all PVT corners and a two-stage dynamic comparator. The important design parameters of the reference voltage buffer are derived in the context of the SAR ADC. The impact of the buffer on the ADC performance is illustrated by simulations using bondwire parasitics. In post-layout simulation which includes the entire pad frame and associated parasitics, the ADC achieves an ENOB of 9.25 bits at a supply voltage of 1.2 V, typical process corner, and sampling frequency of 50 MS/s for near-Nyquist input. Excluding the reference voltage buffer, the ADC achieves an energy efficiency of 25 fJ/conversion-step while occupying a core area of 0.055 mm2.

One way to lower the levelized cost of energy for wave power plants and paving so the way for commercial success, is to increase the power absorption by use of advanced control algorithms. This thesis investigates the influence of the generator inertia, the generator damping and the layout on power absorption and presents a new model free strategy of controlling wave energy converters. The evaluation of all control strategies was done in a numerical simulation and in experimental 1:10 model scale wave tank tests conducted in the COAST laboratory at the University of Plymouth. The WECs used are inspired by the wave energy concept developed at Uppsala University. The influence of the generator inertia on the power absorption was tested with an uncontrolled WEC. Compared to a conventional WEC the power output could be significantly increased for small waves and high wave periods.    As a simple and easy to implement control strategy, a WEC with sea state optimized generator damping was used to create a power matrix. The optimal damping factor depends on both, wave period and wave height. The power absorption increases with the wave height and when the wave period converges towards the oscillation period of the WEC. A genetic algorithm was used to obtain the optimized layouts for wave energy farms, which suggest that the converter should be placed in rows parallel to the wave front, and the position in the array has nearly no influence on the optimal control parameter. Then a collaborative learning approach using machine learning is presented, with several identical wave energy converters in a row to parallelise the search of the optimal control parameter. It was implemented to control the generator damping factor and the latching time. With the latter the power could be increased significantly. / Vågkraft kan bli en viktig del från framtidens elektriska energikälla. Men därför kostnaden per producerat energienheten måste minskas. En väg att minska kostnaden är att förbättra effektiviteten med ett avancerat styrsystem. Den här avhandlingen tester olika kontrollstrategier för att hitta en bra strategi för vågkraftverk i parker. Alla strategier testas med an numerisk simulering och ett fysiskt test med en 1:10 skalad modell i en våg bassäng. Först är en elektrisk vågkraft konverter (WEC) med optimerad naturlig frekvens men utan styrsystem är testad. WECen absorberar hög effekt i ett litet område med de vanligaste vågklimatet. Storlek på området kan varieras med generatorns dämpning och bästa vågperiod kan ändras med WECens tröghet. En generator med optimal dämpningsfaktor testas, för att en justerbar generator dämpning är relativt lätt att implementerar. Numerisk simulering visade att optimal dämpningsfaktor beror på vågperiod och minskar när våghöjden ökar. Beroende av effekten från våghöjd kan ses i numerisk simulation och fysiksals test, men beroende av effekten från vågperiod kan ses bara i numerisk simulation. Därefter, en modell oberoende strategi (som kallas CL) för vågkraftkonverter i arrayer är presenterat och testad för att styra (1) generator dämpningsfaktor och (2) latching tid. Resultat är att den CL kontrollerade generatorn dämpning endast visar små fördelar med absorberat energi. Men med en CL optimerat latching tid, absorberat effekten ökas mer som 100\% i vissa vågklimat. / SUPERFARMS

The main aim of my project is to develop a hardware implementation of the electronic waterheater by choosing different components and minimize the errors in the same. I have consideredseveral options depending on the availability of components, cost, reliability, implementation,financial budget, specification and thinking about the professional technical skills required. Inthis project I designed and implemented, an AVR micro controller based water temperaturemeasurement system using Atmega328p microcontroller.The idea of the project came from a company called Relek production AB, Sweden and theydevelop and supply electrical equipment for heating: such as electric boilers, under floor heatingboilers, IR heaters, emergency power plants, power monitors, etc. Now they want to develop anew version of electronic water heater and according to their specification.The microcontroller (Atmega328p) based temperature control system is used in this project forproviding better functioning of the system and will also serve the following purposes.1) As there will be less usage of energy as it is more energy efficient.2) The microcontroller along with temperature sensor decides when the heater shouldturn on/off.With this project I have designed the schematic diagram by using Eagle Autodesk PCB CADprogram. The seven-segment display is used in this project to show the current temperature. Atemperature sensor (LM35) is used in this project to sense the temperature and give thesemeasured values to the microcontroller. The temperature measurement and heater control areprocessed using C++ program.I have connected the circuit as per the schematic diagram and programed the microcontroller,interfacing all the major components like 7 segment display, temperature sensor, 2 pushbuttons(for manually incrementing and decrementing the set point in the program), and optoisolator (tosense the output from microcontroller and control the heater through thyristor).

Under de senare åren har antalet elbilar ökat i antal och antalet elbilar förväntas också fortsätta att öka under de kommande åren. Då antalet elbilar ökar behövs följaktligen fler laddstationer avsedda för laddning av dessa. Arctic paper Munkedals AB avser att uppföra laddstationer för laddning av elbilar, i första hand för besökande till fabriken. Intill fabriken finns flera parkeringsytor avsedda för personal samt en besöksparkering, ca 120 personalparkeringar har tillgång till uttag avsedda för motorvärmare. Det vore ekonomiskt fördelaktigt att ansluta de tilltänkta laddstationerna till den befintliga anläggningen för motorvärmarcentralerna. Förstudien innefattar en sammanställning av data för befintlig anläggning för matning av motorvärmarcentraler. Utifrån sammanställda data har befintliga kablars belastningstålighet beräknats, resultatet av beräkningarna visar att det i 2 centraler är möjligt att byta till en högre säkring. I rapporten förklaras också övergripande hur elbilar samt laddstationerna fungerar. Från ett urval av leverantörer redovisas produkter som anses vara relevanta för förstudien. Lösningar samt kostnader för dessa har tagits fram utifrån 2 scenarion, där de befintliga motorvärmarcentralerna antingen ersatts av laddstationer eller kvarstår enligt nuvarande utförande. Lösningarna omfattar parkeringsytan vid 40kV ställverket, samt 1 laddstation vid besöksparkeringen avsedd för besökande. Väsentligt för de bägge lösningarna är lastbalanseringssystemet, vilket möjliggör ett större antal laddstationer än vad som annars vore möjligt med avseende på befintlig anläggnings dimensionering. Av de 2 redovisade alternativen för uppförande av laddstationer, anses alternativ 2 där motorvärmarcentralerna ersätts av laddstationer som mest lämpligt att gå vidare med. Alternativet innebär vid en total utbyggnad att 15st laddstationer kan uppföras till en kostnad av ca 525 kkr. Då lösningen är skalbar är rekommendationen att utföra utbyggnaden i etapper, allt eftersom behovet uppstår. Vilket innebär att statistik kring laddning kan sammanställas och analyseras för att få ett bra underlag inför en fortsatt utbyggnad. Genom att utföra utbyggnaden i etapper fördelas den totala kostnaden över tid, initialt innebär ett uppförande av 1 laddstation för besökande en kostnad på ca 110 kkr. / In recent years electric cars has increased in numbers, this increase is expected to continue in the coming years. With an increasing number of electric cars, more charging stations are required. Arctic paper Munkedals AB intends to construct charging stations for charging electric cars, primarily for visitors to the factory. There are several parking spaces for employees located next to the factory, and one parking space for visitors. Approximately 120 of the parking lots for the employees has access to sockets for block heaters. To reduce the investment cost, it is beneficial to connect the intended charging stations to the existing installation for the block heaters. The pilot study includes a compilation of data for the existing installation of the block heaters. Based on the compiled data the maximum current load for the existing cables has been calculated, the result of the calculations shows that in 2 centrals it is possible to switch to a higher fuse. The report explains generally about how electric cars and charging stations work. Products from a selection of suppliers that are considered relevant for this work, are described. Solutions and costs have been developed based upon 2 scenarios, where either the existing centrals for block heaters is replaced with charging stations or remains according to current version. The solutions are covered by the parking space next to the 40kV switchgear and a charging station on the parking lots for visitors. Essential for both solutions are the load balancing system, which enables a larger number of charging stations that otherwise wouldn’t be possible regarding to the dimensions of the existing installation. Of the 2 reported alternatives for the construction of charging stations, alternative 2 where the existing block heaters are replaced with charging stations are considered most suitable to proceed with. With this alternative 15 charging stations can be installed to a total cost of approx. 525 kkr. Because of the scalability of the solution, it is recommended to make the installation of the charging stations in stages as the need arises. This means that statistics for the charging stations can be compiled and analyzed to provide a good basis for further expansion. By carrying out the expansion in stages, the total cost will be distributed over time. Initially this means the construction of 1 charging station for visitors to a cost of approx. 110 kkr.

This master thesis aims to develop a prototype of a wireless sensor network (WSN) using ultra wideband (UWB) radio and communication. The WSN consists of five sensor nodes and one sink which is connected to an Android smartphone. The smartphone acts as a sensor data management unit and has the ability to display sensor measurements. The sensor nodes include the sensors of an inertial measurement unit, an electrocardiogram (ECG) electrode set, a temperature sensor, a humidity sensor, and three ultrasonic sensors, and they are responsible for making measurements, sending the measurements to, and forwarding the measurements from other sensor nodes to the destination. The sink node receives the measurements from the sensor nodes, and the measurements are displayed on the smartphone. The sensor nodes and the sink are equipped with DecaWave's DWM1000 UWB transceiver which is compliant with the IEEE 802.15.4-2011 communication standard and enables the UWB communications, and a microcontroller, ATmega328, that handles sensor data reading and transmission. Due to UWB pulses having high time resolution, a location-based routing protocol based on time of flight distance estimates is implemented. A prototype of a UWB-based WSN has been developed, tested and evaluated. The resulting prototype can operate in a peer-to-peer topology with multi-hop capabilities. The results of the evaluation show that lower data rate, lower center frequency and wider bandwidth increases radio range and a longer preamble sequence increases ranging accuracy. This comes at the cost of increased time of channel occupation and power consumption. From this thesis project it is indicated that UWB radio is a good choice for short-distance radio communication applications such as WSNs. The measurement errors in range estimates can be within 10 cm in line-of-sight. Networks compliant with the IEEE 802.15.4-2011 communication standard should have low throughput requirements as channel access mechanisms and functions related to reliable data transfers introduce latency.