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  • 1.
    Ahmed, Tanvir Saif
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Markovic, Bratislav
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Distribuerade datalagringssystem för tjänsteleverantörer: Undersökning av olika användningsfall för distribuerade datalagringssystem2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis, a study of three different uses cases has been made within the field of data storage, which are as following: Cold Storage, High Performance Storage and Virtual Machine Storage. The purpose of the survey is to give an overview of commercial distributed file systems and a deeper study of open source codes distributed file systems in order to find the most optimal solution for these use cases. Within the study, previous works concerning performance, data protection and costs were an-alyzed and compared in means to find different functionalities (snapshotting, multi-tenancy, data duplication and data replication) which distinguish modern distributed file systems. Both commercial and open distributed file systems were examined. A cost estimation for commercial and open distrib-uted file systems were made in means to find out the profitability for these two types of distributed file systems.After comparing and analyzing previous works, it was clear that the open source distributed file sys-tem Ceph was proper as a solution in accordance to the objectives that were set for High Performance Storage and Virtual Machine Storage. The cost estimation showed that it was more profitable to im-plement an open distributed file system. This study can be used as guidance to choose between different distributed file systems.

  • 2.
    Alameddine, Raged
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Dashtbozorg, Sajad
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Utredning av för- och nackdelar med TN-S respektive TN-C system2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this report analysis the advantages and disadvantages of the TN-C (four conductor system) and TN-S (five conductor system) system. There are different opinion about which system is most appropriate to use in the distribution network and the building main lines. With the help of literature studies and contacts with various power companies and electric companies different opinion have been discussed . TN-C is the most appropriate option in the distribution network and TN-S should be used in the building main lines. This for achieving high and stable electrical environment. This thesis will facilitate the choice of technology and hopefully increase the knowledge about the subject.

  • 3.
    Al-Breihi, Mohammed
    KTH, School of Technology and Health (STH).
    Utveckling av laboration om trefastransformatorn: En studie om transformatorer2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This degree project was carried out on behalf of the unit for Computer

    and Electrical engineering at the School of Technology and Health, KTH.

    This study about transformers, their function and uses, the way they’re

    built, how the core and windings, which are the most important parts of a

    transformer, are made and what kind of materials are used to make them.

    Several types of transformers and their functions are described. A crucial

    part of the study has been to search for different ways to develop

    transformers to make them environmentally safer and to increase their

    life-span. As such this work describes different transformer oils, what

    advantages and disadvantages they have compared to mineral oils, what

    properties they have and in what way they’re less harmful for the

    environment. HVDC units transform high voltages from Alternating

    Current to Direct Current to lessen the resistive losses and energy losses

    which lead to a cleaner environment.

    The theory examination of the transformer is the basis for the formation

    of a lab for educational use, among others in a course about electrical

    power that’s included in Bachelor of Science in Electrical Engineering at

    KTH.

  • 4.
    Andersson, Dan
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Implementation av prototyp för inomhuspositionering2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Development of technology constantly creates new opportunities but it can also mean major chang-es for companies and organizations. Today phones, tablets, laptops, mobile communications and cloud technology make it possible to be no longer bound by the time, location or device in order to work. The change means that a new office type that is more flexible and space efficient due to no fixed workplaces, is becoming more common. A problem with this type of offices that are known as flex-offices is that it is not obvious where or when a colleague is in the office, especially if it is large office with multiple floors.

    The aim of this work is to develop and implement a Location-Based Service for the company Connecta AB. The service will enable users to use their mobile phone to share their current workplace location in an office environment.

    The result of this work is a Location-Based Service that enables a user to use an Android phone with support for Near Field Communcication to share their current workplace position. The cloud-based server solution, Windows Azure is used to store indexed workplace positions.

  • 5.
    Björklund, Johan
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Prestandautvärdering av permanentmagnetmotor2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The project was to evaluate a synchronous three-phase permanent magnet motor with brushless outrunner. It is supposed to be a part of an electric drive system for equipment onboard sailing boats. The goal was to investigate the performance of the motor and find the construction weaknesses and to come up with suggestions how to optimize the performance of the motor.

     

    Tests and measurements were made with a test setup that consisted of inverter, motor and a generator connected to the shaft. The generator stator winding had a short circuit when the load current reached 106,1 A and the tests therefore had to end. The copper wire used in the windings temperature became to high and the isolation of the wire melted.  The tests showed that the motor could handle up to 92,1 A with an efficiency of 70%. It was how much current the winding could withstand together with the power losses that was the limiting factor of the motor construction.

     

    Forced cooling with water cooled stator or improving the winding wires ability to handle higher currents by increasing the cable area are both alternatives to get a better efficiency and motor performance.

  • 6.
    Björnström, Tommie
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Cederqvist, Reidar
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Comparison and Implementation of Software Frameworks for Internet of Things2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There is no established standard for how Internet of Things devices are communicating with each other, every manufacturer uses their own proprietary software and protocols. This makes it difficult to ensure the best possible user experience. There are several projects that can become a standard for how devices discovering, communicating, networking etc. The goal for this thesis work was to compare such software frameworks in some areas and investigate how Inteno’s operating system Iopsys OS can be complemented by implement one of these frameworks. A literature study gave two candidates for the comparison, AllJoyn and Bonjour. The result of the comparison showed that AllJoyn was the most appropriate choice for Inteno to implement into their OS. AllJoyn was chosen because it has a potential to become an established standard and includes tools for easy implementation. To make a proof of concept, an AllJoyn application was created. The application together with a JavaScript web page, can show and control options for an AllJoyn Wi-Fi manager application and AllJoyn enabled lamps.

  • 7.
    Boongerd, Sanhawad
    et al.
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Lindstein, Fredrik
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Analys av datakommunikationssäkerhet för VoIP-protokoll2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Voice over IP (VoIP) is a relatively new technology that enables voice calls over data networks.With VoIP it is possible to lower expenses, and increase functionality and flexibility. FromSwedish Armed Forces point of view, the security issue is of great importance, why the focus inthis report is on the security aspect of the two most common open-source VoIP-protocols H.323and SIP, some of the most common attacks, and counter-measures for those attacks.Because of the level of complexity with a network running H.323 or SIP, and the fact that it hasyet to stand the same level of trial as of traditional telephony, a VoIP-system includes manyknown security-issues, and probably at present many unknown security flaws.

    The conclusion is that it takes great knowledge and insight about a VoIP-network based onH.323 or SIP to make the network satisfyingly safe as it is today, and is therefore perhaps not asuitable solution for the Swedish Armed Forces today for their more sensitive communications.

  • 8.
    Camling, Johan
    et al.
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Lönnegren, Fredrik
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Karttillämpningar för rikstäckande accessnät2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis describes the process of analyzing and evaluating geographic services, and the development of map applications for nationwide networks. The project was performed at DGC, a datacommunications-, telephony- and networks operator which distributes customer access across Sweden where consumers are connected to the backbone network. In whole, the task consisted of an analysis regarding the possibilities of address-to-coordinate lookup for established customer sites, displaying the access network in a map interface and developing one or more tools, aimed at supporting order processes. Architecture patterns, use-cases construed from user requests and analysis of external provider services for geocoding determined the design of the solution. Software was partially integrated in existing systems, and partially distributed as stand-alone applications. The product was finalized with a release. Read further to get a description of the monitoring tool, network mapping with KML, dealing with geographic data, and also the process of fetching coordinates for addresses.

  • 9.
    Cronebäck, Alexandra
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Input interface requirements on board mounted DC/DC converters2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been carried out on behalf of the department of Power Modules at Ericsson.

    In a telecom system interface A is a physical point between the power supply system and the telecommunication equipment described in a European standard called ETSI EN 300 132-2. This interface is also described in the American standard ATIS-0600315.2007. For board-mounted products, such as DC/DC converters, a well-defined input interface description is lacking.

    The goal of this thesis was to evaluate if the requirements in the standards ETSI EN 300 132-2 and ATIS-0600315.2007 are viable for the input interface of DC/DC converters. A part of this goal was also to investigate and analyze how the systems, in which the DC/DC converters operate, works.

    To be able to determine if any of the two standards, ETSI and ATIS, are viable for use for the input interface, both were reviewed and described with focus on voltage levels and transients.

    In the information gathering phase it became clear that an extended limitation was needed. Therefore, in order to investigate what happens from interface A to the input interface of DC/DC converters, the system used in this thesis is the EBS LOD (Ericsson Blade System – Low Ohmic Distribution). EBS is one of the systems in Core sites.

    The report describes the construction of EBS where in the PFM (Power Fan Module), backplanes and various boards are important parts. Furthermore some key principles within Core sites, such as HOD (High Ohmic Distribution), LOD, Two-wire system and Three-wire system, are also described in order to explain how the EBS system works.

    EBS (including PIM (Power Interface Module)) was modeled in OrCad PSpice, with both one board and 26 boards, and was simulated with different transients at an input to the system. The simulation results show that the high voltages never reach the DC/DC converter and that they therefore are well protected from transients in an EBS LOD system.

    In order to determine whether the standards ETSI and ATIS are viable for the input interface of DC/DC converters, it is concluded that more investigations, tests and simulations are needed.

  • 10.
    Dahlberg, Axel
    et al.
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Francén, Jonas
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    IPv6-adresshantering och prefixdelegering i MPLS VPN-nät2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Full migration to IPv6 brings the need to adjust datacommunication services for the new generationof IP protocols with maintained or expanded functionality. This thesis’ goals is to submitone or more solutions that meets requirements and the technical conditions that enables thecompany DGC:s to expand the service IP-VPN for IPv6. This includes address assignmenttechniques like prefix delegation and automatic address configuration in existing network infrastructure.Solutions are presented in six scenarios that have been investigated considering tests, analysis andexperienced problems. The investigation formed the criteria scalability, configuration complexity,compatibility, support by RFC:s and requirements stated by DGC that adds to the evaluationof the most suitable solution.The evaluation has resulted in a recommended scenario that is implementable according to givengoals.Techniques that may influence the choice of most suitable solution, but that is not yet available,are discussed and presented to point out what may needed to be considered in the future.

  • 11.
    Duvheim Bruce, Adam
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Indreeide, Ole Martn
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Beräkning av återmatad bromsenergi på Malmbanan2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Energy is a limited recourse and the use of energy has to be as effective as possible to avoid harmful effects on the environment and to cut spending. Reusing the energy the ore train uses to climb the mountains of northern Sweden through regenerative breaking leads to a more effective use of energy. Calculation of energy uses the trains’ stored energy and the losses during its journey along Malmbanan. This results in a total power save of 20 % for single track and between 20 % and 21 % for double track. Traffic on double track can increase but the relationship between regenerated and consumed energy will be the same. Regenerating energy on the railway reduces today’s negative impact on the environment and leads to savings in energy cost for the company.

  • 12.
    Edlund, Fredrik
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Sarker, Saqib
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Smart Kitchen: Automatisk inventering av föremål2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Internet of Things is growing fast and is predicted to become a part of everyday life. This can be used to create products which will make everyday life easier. Automated object detection combined with an automated inventory check can make it easier to manage what is in stock, this is something that can be used in smart refrigerators as an example, to make life more convenient through Internet of Things. This Bachelor thesis studies methods regarding object detection with the purpose to build a system which automatically identifies objects and manages the inventory status. A prototype was built and tested to see what the possibilities there is with such a system. The Prototype uses a Raspberry Pi as core unit, which uses Dlib libraries to identify predefined objects. The user will identify unknown objects via the mobile phone application, which makes it possible for the system to learn how to identify new objects. The same application is used to check the inventory status for the different objects that has been identified by the system. The prototype can identify objects and learn to identify new ones, according to the goals of the project.

  • 13.
    Engström, Magnus
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Soheily, Nadia
    EKG-analys och presentation2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The interpretation of the ECG is an important method in the diagnosis of abnormal heart conditions and can be used proactively to discover previ-ously unknown heart problems. Being able to easily measure the ECG and get it analyzed and presented in a clear manner without having to consult a doctor is improtant to satisfy consumer needs.

    This report describes how an ECG signal is treated with different algo-rithms and methods to detect the heartbeat and its various parameters. This information is used to classify each heartbeat separately and thus determine whether the user has a normal or abnormal cardiac function. To achieve this a software prototype was developed in which the algorithms were implemented. A questionnaire survey was done in order to examine how the output of the software prototype should be presented for a user with no medical training.

    Seven ECG files from MIT-BIH Arrhythmia database were used for validation of the algorithms. The developed algorithms could detect of if any abnormality of heart function occurred and informed the users to consult a physician. The presentation of the heart function was based on the result from the questioner.

  • 14.
    Eriksson, Niklas
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Lifvendahl, Patrik
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Utbildningssimulator av funktioner i spårfordon: Hårdvarusimulator med felsökning på dörrsystem2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report is a description of a developed educational simulator over rail vehicles and its components. The simulator is a hardware-based prototype over a door system on rail vehi- cles. System specialists and technicians will use the prototype. The Simulator should give the user a technical demonstration on how components work in a door system. The proto- type consists of motor, switch, relay and sensor. The components are used for illustration of the functions in a door system on a rail vehicle. The educational simulator is controlled with a control unit and with pushbuttons for manual control. For demonstration of the boarding security an optical sensor is used as symbolize for the obstacle detection.

    The educational simulation has two embedded common faults: cable fault and ground fault. The instruction manual consists of a circuit diagram and is used for troubleshooting. The circuit diagram over the door system is used to find the faults and to correct them. The fault analysis includes the factors, which is the reason for the most common faults to occur in a rail vehicle. Door system receives diagnostic code from a door computer that control priori- tizing for arrangements that will be made. 

  • 15.
    Ernmark, Niklas
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Utveckling av en CAN-adapter i ett sensorsystem för övervakning av däcktryck.: Development of a CAN-adapter in a sensor system for tire pressure monitoring.2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes a degree project at the Royal Institute of Technology. The purpose was to create a unique system solution in which a CAN adapter card (Controller Area Network) was to be integrated with an air pressure monitoring system for heavy duty vehicles. The goal was to present measurement values ​​from valve sensors on a personal computer. The air pressure monitoring system is called J1939 - TPMS and is a finished product. J1939 - TPMS sends CAN-frames to a CAN-bus in J1939 format. These frames are to be read by the adapter card and presented on a terminal program on a personal computer. The job has been to investigate how the J1939 - TPMS system works in detail. The role of the J1939 protocol and its relationship with CAN has been clarified. Also, a detailed description of how J1939 frames are interpreted and how the measuring data TPMS is decoded is done. Principles for how a CAN node works has been clarified. Based on this, a CAN adapter card has been designed. The design has included component selection, design of electronics schema, design of computer cards and development of embedded software. The result was a ready-to-use CAN adapter card tested with J1939-TPMS. Requirements for the project were met. However, more work with the card will be needed to make it a finished product. The work was carried out at Motion Control in Västerås AB in cooperation with Transeco Däckservice (Transeco Tire Service).

  • 16.
    Ezzeddine, Kassem
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Oskarsson, Robert
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Analys av kondensatorbatteriers tillkopplingsfenomen: Undersökning av de kopplingsfenomen som uppstår vid tillkoppling av kondensatorbatterier och deras påverkan på närliggande komponenter2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Many electrical devices need reactive power to operate. Transmission of reactive power occupies a proportion of the available capacity in the power system and therefore capacitor banks are used near to the end user to generate reactive power. Thus, the reactive effect is generated and consumed in a separate part of the power system. Capacitor banks switching causes transients which may damage the surrounding components.

    Based on the real substation Stallbacka in Trollhättan, this study has analysed capacitor banks switching transients within the medium voltage level. The analysis has covered the size of these transients according to different conditions and scenarios. The result showed that the transients in this case never reached serious levels, thus there was no impact on the components. It is not clear whether the transients affect the power quality because there are no defined limits. 

    A calculation tool to the predicted transients was supposed to be created in the process. This calculation tool was never completed due to the unmanageable solution that was obtained.

  • 17.
    Gabrail, Philip
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Samuelsson, Sam
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Analys av fältfördelning i kabelavslut av linjära och icke linjära material: Analysis of the field distribution in cable termination by linear and nonlinear material2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nowadays XLPE high voltage cables are used in transmission and distribution of electrical power and has an important role in the electrical system. Power transmission that occurs over long distances is diverted from one point to another and is done with the help of cable terminations. These cable terminations have some vulnerabilities that affect the entire power system.

    The theoretical part of the report was carried out with the help of FEM software Comsol Multiphysics. Results showed that the highest field concentration occurs at the insulation of the cable and caused malfunction and vulnerabilities. In the linear case for the electrical part resulted a high permittivity that the potential and the electric field was reduced, which showed the same result for low conductivity. For the nonlinear material the conductivity changes with the electric field and time.

    The temperature of the linear case showed that at high temperatures the material became more conductive. In the nonlinear case the conductive material was reduced. This could be controlled with different threshold value (Eb) which cannot in the linear case.

    The practical part was done in E.ON:s laboratory for different type of cable terminations that were tested with 33kV. Some of the tested cable terminations were used for testing purposes and was picked out of operation because of a malfunction in the cable. An attempt to control field concentration was carried out in the laboratory and resulted to a reduced field  istribution in the cable termination. The result of the practical part showed how the field concentration was distributed in the cable termination and that the field distribution led to the collapse of the cable.

  • 18.
    Gerkens, Rick
    et al.
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Berg, David
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Elkvalitéproblem vid varvtalsstyrd motordrift i industrimiljö2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Harmonics caused by variable speed drives create problems in industrial systems. The purpose of this study is to identify these problems and give recommendations to avoid them. The study was conducted as a bachelor thesis at the Royal Technical University in Stockholm, Sweden for the consultant company Ramboll Energy. A literature review was combined with electrical power quality measurements on variable speed motor operations conducted at Sandvik Mining in Sandviken, Sweden.

    Electrical quality problems caused by variable speed drives origin mainly from frequency inverter control that gives a non-linear current usage which, if the grid is not strong enough, affects voltage quality. Examples of problems are production downtime, disruption and malfunction of equipment and increased wear of equipment.

    This study shows that when making changes in systems containing harmonics, future harmonic levels can be approximated in some cases. Measurements before the change provide input data to model the system, describing the load as a harmonic current generator. With some assumptions on the grid impedance, calculating an approximation on harmonic after the change is possible.

    This study has used a simplified model for the prediction of harmonic levels after a change in the system. The purpose is to propose a cost effective way to approximate so that information on how to prevent problems …in the decision making. Electrical power quality problems could be prevented more often and not doing that is a waste of economical, environmental and social resources.

  • 19.
    Gidlöf Örnerfors, Linus
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Testautomatisering av linjärmotorer2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This diploma work has been carried out on behalf of Stegia AB. Stegia manufacturesand sells linear motors that are tested in a test bench before shipped to thecustomer. Today there is a need for a test bench that collects test results from theperformed tests. The company would like to lower the risk of falsely made tests,and to make the test bench easier for the production staff to use. At this moment,the test of the linear motors is made up of several manual tasks before the test iscompleted. This increases the risk of wrong results because of incorrectly madetests, with no traceability of the results. The goal with this diploma work is to lowerthe risk of incorrect test result by automating the testing process for the productionstaff. The result is presented as a prototype, that should increase the reliability ofthe test result of the motors. The result is then validated and analyzed in this report.

  • 20.
    Grahn, Erik
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Evaluation of MEMS accelerometer and gyroscope for orientation tracking nutrunner functionality2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the production industry, quality control is of importance. Even though today's tools provide a lot of functionality and safety to help the operators in their job, the operators still is responsible for the final quality of the parts. Today the nutrunners manufactured by Atlas Copco use their driver to detect the tightening angle. There- fore the operator can influence the tightening by turning the tool clockwise or counterclockwise during a tightening and quality cannot be assured that the bolt is tightened with a certain torque angle. The function of orientation tracking was de- sired to be evaluated for the Tensor STB angle and STB pistol tools manufactured by Atlas Copco. To be able to study the orientation of a nutrunner, practical exper- iments were introduced where an IMU sensor was fixed on a battery powered nutrunner. Sensor fusion in the form of a complementary filter was evaluated. The result states that the accelerometer could not be used to estimate the angular dis- placement of tightening due to vibration and gimbal lock and therefore a sensor fusion is not possible. The gyroscope by itself can be used to provide the angular displacement around every axis with high accuracy without taking into account the gimbal lock phenomena or external forces in the form of vibration of the tool. The gyroscope provided data with a probability to measure ±1° in future tightenings by 69,76%. The gyroscope provided data with high accuracy and stability and can be used in real world application and production for true angle functionality of the tools. 

  • 21.
    Grip, Johan
    et al.
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Djampou, Serge
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Elkraftsystem för fälttest av Polygeneration system EXC2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In a modern society electricity is a key component for the development of the individual, industry, and society. Natural disaster areas where the electricity has been knocked out face great trials in order to get vital public functions working again. With the help of the mobile eco-friendly energy device Emergency Energy Module (EEM) electricity needs can be eased.

    The goal of thesis was to produce an electrical power system description for the upcoming Export container (EXC), and to generate a correct circuit diagram for the existing Emergency energy module (EEM).

    The electric power description must take into account EXC's specifications and include Bills of Material (BoM) and circuit diagram. The problems lies in getting the various sources of energy (solar, wind and biomass gasifier) to work together in a power system where DC, AC, three-phase and single-phase are mixed. Great emphasis is also given to obtain a flexible electricity systems that can be relatively easily changed for different customer needs.

    The making of this thesis was carried out initially with a gathering facts phase. This was followed by a review and analysis of the EEM's electrical system which resulted in a circuit diagram and a manual.

    Weaknesses in EEM's electrical system was considered to be the lack of overvoltage protection and residual current device, measuring point 5 was misplaced, measuring equipment should for safety reasons be firmly attached and 1-phase generator should be used in biomass gasifier to remove uneven load problems. The existing Power router, whose task is to control the energy flow in the system, was limited because it could only receive one AC power source, handle only one-phase and had a relatively low maximum output power of 5.5 kW.

    Whit the help of the analysis improvement suggestions above and with EXC's specification taking into account was then an electric power system for EXC constructed. with associated BoM, circuit diagram, specifications for subsystems and proposals for candidates that meet these.

    The electrical system is recommended to be built around the Power router Quattro which provides great opportunities for flexibility in terms of being able to scale up the system if such more power would be desired by the customer, or if there is a need for 3-phase systems. A variety of programming settings can then be made which facilitates the construction of specific electrical systems for varying customer needs.

  • 22.
    Gustavsson, Robert
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering. KTH.
    Lind, Alexander
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering. KTH.
    Utvärdering av energiförbrukning av ett IoT-system för övervakning av hundars rörelsemönster2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Tracy Trackers is currently developing an AI platform which purpose is to monitor a dog's movement pattern. The platform consists of hardware with accelerometer, gyroscope, temperature and humidity sensors attached to the dog. The hardware is connected to a mobile through Bluetooth. A study was conducted to investigate which batteries that are available on the market and which ones that fit best for the prototype. The aim of the study was to find a rechargeable battery with long operat-ing hours that is economically and environmentally viable for future production. Hardware for monitoring the battery voltage characteristics was built to determine differences between kinds of batteries and if there was an optimal type of battery for the specific product. The sensors used by the prototype were studied using os-cilloscopes and a self-constructed circuit in order to be able to determine power consumption at different sampling frequencies. Furthermore, a circuit was built for filtering out certain frequencies to determine the current consumption of the DC-components. The current consumption measured by the tests in this study refers to what draws current in the prototype. The developed hardware can be used for measurements of future prototypes

  • 23.
    Haidari, Bahaman
    et al.
    KTH, School of Technology and Health (STH).
    Holm, Isak
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Verifiering av ERTMS-signalprojektering: Tillämpning mot Estland2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    EU has a framework that strives to interoperability to make it easy to travel and do business with all nations in the EU without the need to change trains or drivers. This report discribes the various laws and regulations that issued and specified by the EU Commission, UNISIG and the Swedish national rules that apply for ERTMS signalling project planning for trackside equipment. Today there is a need to more efficient the signal project planning. To achieve this, a checklist for signaling project planning will be developed that clear show, for example, where an Eurobalise in relation to a signal point should be located by referring to the correct subchapter in the right document.

    The mission of the project is to make it easier to design new production of ERTMS signalling project planning. To make this be possible studies has been done to TSI, SUBSET (the documents that controls and regulates the ERTMS signalling), relevant documents and analysis already implemented signalling project planning on Ådallines.

    The report presents a compilation of the signal project and how the different phases will occur, how they will be implemented and their significance.

    In this report, the group has produced a complete compilation of the processed documents for ERTMS signalling project and a checklist for verification of the ERTMS signalling project.

  • 24.
    Herrlin, Emma
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Alternativa reglermetoder för en energieffektiv byggnad2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Ungefär 60 % av den totala energianvändningen för uppvärmning (inklusive varmvatten) i Sverige går åt till att värma upp flerbostäder och lokaler, vilket ger en indikation på att det finns potential att minska energianvändningen ytterligare genom att hitta alternativa metoder för styr- och reglering av befintliga värmesystem. En viktig faktor oberoende av vilken metod som används är att veta byggnadens dynamiska egenskaper. Det finns en rad olika metoder på marknaden för att kunna minska energianvändningen och en del av dem är välbeprövande medan andra fortfarande är på forskningsnivå. Den beprövade metoden är prognosstyrning vilket också utvärderades vidare i examensarbetet genom en studie av tidigare utförda arbeten inom området. En gemensam och viktig faktor för att kunna spara energi för uppvärmning i byggnader är att veta byggnadens tidskonstant, även kallad värmetröghet. För att påvisa dess betydelse utfördes simuleringar i ett program som heter TEKNOsim som är utvecklat av Chalmers tekniska högskola. Resultatet från simuleringarna som utfördes för 6 olika scenarier visade att den stora faktorn som påverkade byggnaden var internvärmen från belysning, apparater och personer. En yttre påverkande faktor som också hade betydelse var solavskärmning för fönsterna vilket gav en jämnare rumstemperatur. Då simuleringarna anpassades till två olika driftfall för ventilationssystemet till ”kontorstid” och ”utanför kontorstid” höll sig rumstemperaturen inom ramen för högsta och lägsta temperatur under tiden då kontoret var bemannat. En annan metod som användes var en litteraturstudie för arbeten inom området prognosstyrning. För de arbeten som valdes ut undersöktes två olika leverantörer som är marknadsledande i Sverige, eGain och Kabona. I snitt visade resultaten en besparing på 10–15% för uppvärmningskostnaderna men den individuella spridningen för eGains prognosstyrning var stor. Vissa fastigheter hade ingen besparing alls medan andra hade en besparing på 26%. Den stora spridningen berodde antagligen på att det nya systemet endast varit igång i 6 månader då studiens utfördes, vilket är för kort tid för att få några tillförlitliga resultat. För Kabonas tjänst Ecopilot var resultaten mer jämna.

  • 25.
    Isaksson, Marcus
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Utvärdering av Windows RT för portning av Mario Framework2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Ericsson har utvecklat ett ramverk för multimediakommunikation som heter Mario. Mario kan användas för att sätta upp video- och ljud-samtal över IP och finns fungerande på Android och iOS. Mario är en del av web browsern Bowser som finns att hämta på Google Play eller App Store. Bowser möjliggör att köra WebRTC applikationer skrivna i HTML5 och JavaScript på Android och iOS.

    Nu när Microsoft släpper sina nya plattformar, Windows RT, Windows 8 och Windows Phone 8 så finns ett intresse att försöka flytta detta ramverk till dessa plattformar. Vi kommer göra ett försök att porta Mario till Windows RT. Anledningen till att Windows RT valdes är för att det är den första plattformen att släppas av de tre nämnda produkterna.

    Plattforms APIet som används i Windows RT kallar för Windows Runtime (WinRT). Många delar av det här APIet delas med Windows Phone 8 och hela WinRT APIet exponeras i Windows 8. Det här betyder att förutsatt att koden designas på rätt sätt så borde den gå att flytta mellan Windows RT, Windows 8 och Windows Phone 8 utan problem. Windows RT är ett operativsystem utvecklat för att fungera på datorer som använder ARM-baserade processorer.

    För att Mario ska kunna fungera på WinRT så måste följande mål uppfyllas:

    • De open-source bibliotek som används av Mario måste byggas på Mario.
    • C/C++ kod måste kunna köras på Windows RT plattformen.
    • Mario ramverket måste integreras med video- och ljudfångning i operativsystemet.

    Vad det gäller open-source projekt så ligger det under en sådan licens (LGPL) som gör att källkoden inte får ändras utan att hela källkoden till de projekten som använder open-source koden också släpps som open-source. Ericsson vill inte att Mario ska släppas som open-source utan vill själva ha kontroll på källkoden. Av denna anledning kommer vi utreda om det är möjligt att bygga dessa bibliotek utan att ändra i koden.

    I och med att Mario är skrivet i C och C++ så måste det också utredas hur vida det är möjligt att köra C/C++ kod i Windows RT. Vad det gäller video- och ljudfångning måste Windows RT APIet utredas för att se hur man använder det för just detta.

  • 26.
    Johansson, Charlie
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Frid, Martin
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Inomhuspositioneringssystem: Personlig navigation inomhus via mobiltelefon2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The GPS is used today for personal navigation, however GPS performs less well in an in-door environment due to the dependency of line of sight. The IPS, Indoor Positioning Sys-tem, will complement the function of the GPS and open doors for new applications. In this thesis studies of methods and techniques are made to enable IPS for a portable device. These techniques and methods are verified that they could be implemented in a smartphone.A prototype was designed to examine the possibility to navigate in an indoor environment. The prototype was built on a RSSI-based radio fingerprinting method over Bluetooth. This method was integrated with a dead reckoning system using an IMU to follow the motions of the user. Tests and simulations are performed along with the results presented in tables and figures. The result shows that it is possible to navigate using the prototype with a mean error of 0.26m. Results are also showing that two methods are to prefer, as they will com-plement each other’s weaknesses.

  • 27.
    Karlsson, Kristoffer
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Den intelligenta pumpstationen -Optimering av energiförbrukningoch utveckling avautomatiseringsfunktion förfelhantering2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This paper has investigated the possibility of optimizing the power consumption of pumps through the control system for a wastewater pumping stations. Further-more, the possibilities of developing new control functions has been investigated, with the purpose to simplify the operation maintenance of the station. To investigate energy consumption, a theoretical model of a pumping station has been made where energy tests for three different control methods have been per-formed. Two of the methods studied were on/off control and a P controller which are commonly used in pump stations. The third method was a Fuzzy controller which, with regard to the level and level change, regulates the speed of the pump.The results from the energy tests showed that on/off control consumed most en-ergy and the Fuzzy controller demonstrated best features to optimize energy con-sumption. The Fuzzy controller’s energy consumption was less in most of the tests compared with the P controller. The Fuzzy controller showed the best properties when the inflow was low relative to the pump’s capacity and the bottom area of the sump was smaller.When investigating new control functions, interviews with management executives has been made to get a picture of the problems that may occur in a pump station. The control functions developed had the purpose of reducing the number of clogged pumps as this was the biggest problem.

  • 28.
    Karnik Macaya, Yohanna
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Vattennivåreglering i Avesta Lillfors: På uppdrag av Fortum Generation AB2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report evaluates different methods to create a stable regulation of the water level in the hydro power plant Avesta Lillfors, in county Dalar-na. Another pair of plants are located just 900 m up the stream, which is why the regulation has to act fast. If the water level can be regulated and automatically adjust to the incoming flow, it facilitates the control of the plant.

    A flow chart is created from measurements in the turbine, using the Win-ter-Kennedy method. The results are used for feedforward control. A PID-regulator with feedback is also simulated in a model of the river. This helps finding the parameters that provide a stable, accurate and fast regu-lation. Fuzzy logic control has also been simulated.

  • 29.
    Kers, Simon
    KTH, School of Technology and Health (STH), Data- och elektroteknik (Closed 20130701).
    Configuration and device identification on networkgateways2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To set up port forwarding rules on network gateways, certain technical skills are requiredfrom end-users. These assumptions in the gateway software stack, can lead to an increasein support calls to network operators and resellers of customer premises equipment. Theuser interface itself is also an important part of the product and a complicated interfacewill contribute to a lessened user experience. Other issues with an overwhelming userinterface include the risk of faulty configuration by the user, potentially leaving the networkvulnerable to attacks.We present an enhancement of the current port forwarding configuration in the gatewaysoftware, with an extensible library of presets along with usability improvements. To helpusers with detecting available services, a wrapper for a network scanner is implemented, fordetecting devices and services on the local network. These parts combined relieves end-usersof looking up forwarding rules for ports and protocols to configure their gateway, basingtheir decisions on data collected by the network scanner or by using an applications nameinstead of looking up its ports. Another usability improvement is an internal DNS service,which enables access to the gateway interface through a human-memorable domain name,instead of using the LAN IP address.Using the Nmap utility for identifying services on the network, could be consideredharmful activity by network admins and intrusion detection systems. The preset libraryis extensible and generic enough to be included in the default software suite shipping withthe network equipment. Working within the unified configuration system of OpenWrt, thepreset design will add value and allow resellers to easily customize it to their services. Thisproposal could reduce support costs for the service operators and improve user experiencein configuring network gateways.

  • 30.
    Klint, Simon
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Laveskog, Magnus
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Energiövervakning och styrning av snarta hem2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Energy monitoring can lead to lowering energy consumption. This infor-mation would help the user to make decisions in regards to the power us-age. The measurements can also give the user the possibility to study the power quality to find bad loads and minimize the effects on the power grid. The choice of thesis was done to give the users the possibility to affect and monitor their environmental effect in a way that is otherwise not possible. A concept was developed that measure the voltage and current peak, the voltage and current RMS, power factor and the voltage waveform. The measurements are then sent to a server that is also containing a website. With the website the user can monitor their power usage and turn on or off the power consumers on the website. Added to the system is also the pos-sibility to add external sensors to increase the monitoring. The result of the project is a functioning concept to demonstrate. Another big result is the amount of improvements discovered to make it a really good base to con-tinue developing on.

  • 31.
    Köyluoglu, Emre Sekvet
    KTH, School of Technology and Health (STH), Data- och elektroteknik (Closed 20130701).
    Värmestrålning för förebyggande av isbildning på strömskenan2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This dissertation has been written with the request from Trafikvörvaltningen. The study's main goal is to investigate whether it is possible to use heat radiation against the surface of the third rail to prevent ice creation during the best efficient of absorptivity.

  • 32.
    Lundmark, Staffan
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Ekholm, Gustav
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Successiv transponering av luftledningar för högspändväxelström2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Three phase high voltage alternating current overhead line systems are associated with losses along the lines and disrupting magnetic fields surrounding the conductors. These negative effects could possibly be combated by twisting the conductors. The twist was achieved by gradually shifting the conductors positions (transposition) over each span of transmission line. A test circuit with a stainless steel wire was made. Geometric and electromagnetic modelling of a successively transposed power line was performed. A miniature three phase overhead line model was constructed.. The model was based on the results from the geometric modeling and data from a real △-configured power system application. Experiments were made with both the steel wire circuit and the overhead line model. Voltage drops in the circuit with a straight - and twisted wire was measured with an oscilloscope. Magnetic flux around the overhead line models were measured with a solenoid. The results from the experiments showed that twisting the conductors resulted in an increase in inductance and a decrease in capacitance. Regarding the magnetic fields, indications of an overall decrease was observed with the twisted configurations compared to the straight. Twisted overhead lines could be viable when an overall decrease in magnetic field is needed. Due to uncertainties in the magnetic field measurements, more extensive experiments should be conducted in order to solidify the results of this work.

  • 33.
    Moradinia, Pourya
    et al.
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Haule, Godfrey
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Portabla enheter: Hot, risker, sårbarheter, lösningar och skyddande motåtgärder2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been written on behalf of the Swedish Armed Forces (Försvarsmakten). The objective of this thesis is to investigate the threats, risks and vulnerabilities that can be caused by portable devices within an organization. Laptop computers with operative system Windows and Mac, tablet PCs and smart phones with operating system Android, iOS and Windows Phone are the only portable devices that have been selected to be part of this report. Proposals on how to prevent these risks are discussed in this work. The report also discusses today's BYOD solutions. Examples of different products from known companies are admitted to more easily describe the actions of the threats, risks and vulnerabilities caused by the portable devices mentioned. Different methods and security solutions are discussed to simplify the understanding of the severity of problems and security risks caused by the portable devices.

     

    The mobile technology has recently become powerful and as a result large enterprises, government workers, small business and private consumers are all using smart phones or other mobile devices to manage both business and personal interactions. Increased employee productivity, improved client services and reduced IT cost are some of the advantages of using mobile devices in an enterprise. Securing these devices at the enterprise level has become a challenge for many IT security experts due to the fact that mobile devices have limited resources (memory, CPU, hard disk space and battery). Therefore, hackers are discovering the economic potential of attacking mobile devices on a course to compromise both business and personal data contained within mobile.

     

    An ideal mobile security solution would be one that is compatible with all the major mobile platforms on the market. Moreover, it would have the capacity to protect data stored on the device as well as data sent between devices or between a portable device and an enterprise network. This solution should also be tailored to the needs of an authority or any large organization, while it also has to be resource-efficient, given that mobile devices tend to have limited resources. Unfortunately at the moment there is no such solution on the market. Therefore, a company or authority at the moment should look around for two or more appropriate mobile security solutions that can be combined to achieve the best possible security level in accordance with their current security policies.

  • 34.
    Nogén, David
    et al.
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Jonsson, Jennifer
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Matbudgetapplikation2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Multiple new services such as “Mina utgifter” and “Smartbudget” show that there is an increased interest among consumers to plan their economy. Groceries represent a large part of the average households budget and is thereby an important thing that can make a large difference in every households economy.This thesis will examine the possibilities to compare food prices with help of an Android application and by taking pictures of the text on receipts. The text will then be processed and sorted to get the necessary data which later can be saved into a database. Premade algorithms and OCR-engines have been evaluated and implemented directly into the Android application by using so called C-Libraries. This makes it possible without major efforts to further develop the application for IOS or Windows Phone.This project and the Android application show the possibilities to use premade libraries and the phones camera to extract and save the necessary information that is relevant for consumers.

  • 35.
    Nordvall, Andreas
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Agile regression system testing2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes the work on automating the testing of nodes at CCS (Common Control System) in Ericsson. The goal was to every three hours configure nodes with the latest build and run the tests. This process is to be fully automatic without user in-put. The existing configuration tool CICC (Core Integration node Control Center) is to be used for configuration. Before work started fault reports were analyzed and creating a usecase for testing restarts should reduce some faults.The first step was to make the configuration tool CICC automated. To schedule the test-ing the continuous integration tool Jenkins was used. But Jenkins can’t by itself run CICC nor interpret the result. Therefore a wrapper layer was implemented. When the wrapper is finished it stores the results of the configuration run in a XML (eXtensible Markup Language) file, which Jenkins reads. Results can then be seen in Jenkins through web interface. If there were any failures during configuration or testing the failed step will have an error message.The project shows that automation is possible. Automating the testing reduce the time for correcting errors because they are more likely to be found early in the process. Be-fore implementing this project in production some improvements should be made. The most significant improvement is making the configuration and testing of each node par-allel with each other, in order to make the time limit for configuration and testing less of an issue.

  • 36.
    Orrevad, Gustav
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Ömsesidig koppling mellan parallellgående friledningar2015Independent thesis Basic level (university diploma), 180 HE creditsStudent thesis
    Abstract [en]

    Parallel overhead power lines induce voltage in one another, which in turn drives a current. In this report an investigation is made in how asymmetrical short circuits on an overhead power line influence the cur-rent in a parallel overhead power lines due to the inductive coupling be-tween the power lines and which hazards it can cause for the electrical delivery dependability as well as high voltage workers.The aim with this bachelor thesis is to increase the accuracy in fault cur-rent calculation in the Vattenfall electricity grid as well as to increase the knowledge within Vattenfall of the phenomena of inductive coupling and the hazards which comes with it.The report could ascertain that inductive coupling can lead to danger for electrical delivery dependability and that there exists a need of analysis on specific parallel overhead power lines within the Vattenfall electricity grid.

  • 37.
    Papadakis, Alexander
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Falge, Emil
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Sensorbaserad riskbedömning av belastningsbesvär2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Musculoskeletal disorders (MSD) is a rising problem in society leading to several socio-economic problems. In combination of the trend of an aging population, MSD can cause even more challenges in the future. Expanding the knowledge of ergonomics is a good way to reduce the risk of stress injury. Today, a visual assessment of ergonomics is primarily used. These observations are individual and not consistent. Availability of cheaper and smaller Inertial Measurement Unit (IMU) has increased the possibility of using objective measurements instead of subjective observations.

    In this thesis work, the Texas Instruments SensorTag CC2650 was used as a sensor, because it is cheap and has many built-in sensors where the 9-axis motion sensor was the most sought one. A web-based development environment called Node-RED was used to develop a prototype and the sensor was connected to a smartphone along with Texas Instruments own application. The data from the sensor was sent from the smartphone to the web application. Measurements were performed on an arm to measure the load on a shoulder, when the hand's position passed the height of the shoulder it indicates that there is a risk of musculoskeletal disorders after an amount of time. To calculate the angle of the arm, sensor fusion of an accelerometer and a gyroscope were used together with a complementary filter.

    Developed system was evaluated by series of tasks exposing the shoulder to a higher risk e.g., painting compare to lower risk tasks e.g., paper sorting. It turned out that measurement are useful for assessment of the risk. However, there are known limitations like low sampling rate of 5Hz (due to limitation in the android app from Texas Instruments). Adding magnetometer to the sensor fusion and evaluation of reliability of calculations are the next natural steps for future work.

  • 38.
    Papp Aminnejad, Benjamin
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Wieweg, Daniel
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Magnetfält i elkraftanläggningar: Ett projekteringsverktyg i Excel för bedömning av magnetfält från elkraftsutrustning på lågspänningssidan2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The exposure of ELF (Extremely low frequency) magnetic field generated by today’s electrical power system, is something that is relatively new to the human body and it is constantly increasing as more technology is developed. As there is no clear answer on how the field actually affects the body, a measure of caution is applied to ensure that the exposure levels are kept down to make sure no harm is done. With the help of previous research in the field, measured values from different locations and approximate calculations, a tool was developed in Excel to estimate the magnitude of the magnetic fields. The tool provides information about the magnitude of magnetic fields from transformers, switchgears, switchboards, powerlines and busbars. The user enters a number of parameters and the tool provides output data with the magnitude of the magnetic field at different distances from the source. This is presented in the form of a table and a graph for each equipment. Since the magnetic field is generated depending on the currents direction, the actual geometry of the electrical system needs to be taken in consideration when calculating the exact magnetic field. This requires an advanced simulation software to be accurate. With this tool, designers have the opportunity to estimate the magnetic fields at an early stage of development.

  • 39.
    Pedral, Jacques
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Abriren, Josef
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Analys av lågspänningsfördelning till signalanläggningar2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report identifies how the system design of low voltage power distribution of the railway can be more cost effective. In the current situation there is a norm on the system design that tends to be replicated each year. This has brought a lack of innovation in the field.

    The purpose of the thesis was to come up with two model stations with the interlocking system M11 respectively M95, where the positioning and nominal size of the UPS:s would be determined to provide a cost effective solution. Furthermore, the cable dimensioning of the model stations was computed as well as the possibility of replacing UPS-systems with rectifier-systems. The model stations were based on two already existing operating sites, Fagersta C (M11) and Skänninge (M95). Lastly, different energy storage alternatives for UPS-systems were compared to acquire the most appropriate choice.

    Through simulations and calculations in, inter alia, the computer program El-Vis, the low voltage power distribution was dimensioned for the model stations. The thesis shows that a distributed UPS-system is preferred in an economical point of view compared to a centralized UPS-system. Furthermore, the thesis establishes that the rectifier system Rectiverter can replace UPS:s. It also states that accumulators are the most suitable alternative for energy storage.

  • 40.
    Persson, Mikael
    et al.
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Andersson, Tim
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Utveckling av en Quadcopter2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The goal of the thesis is to build a quadcopter that can fly and be controlled via a radio transmitter in all directions, stabilizing itself in the air, to land autonomously and detect collisions in the forward direction.In order to achieve the basic goal of being able to fly, a PID controller was implemented which is used to stabilize the Quadcopter in the air by controlling the motors with help from sensor orientation. This sensor orientation is obtained from a complementary filter that merges angle data from an accelerometer and a gyroscope. Both an accelerometer and a gyroscope are required to automatically stabilize the Quadcopter in the air.To achieve the goal of autonomous landing an ultrasonic sensor was used. An algorithm was developed to read the distance from the ground which was a basis for creating our own algorithm for autonomous landing.The Quadcopter has the ability to stabilize itself in the air, be controlled via a radio transmitter and land autonomously. A safety feature that enables autonomous landing if the Quadcopter travels outside the radio coverage is implemented and also a switch that turns off the engines. The only thing that wasn’t implemented was the crash avoidance in the forward direction because the ultrasonic sensor was not suited for this application.

  • 41.
    Rahme, Daniel
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Utveckling och mätning av följdetekteringsalgoritm för V2V med hänsyn till tidsfördröjning2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Traffic accidents are a problem in today’s society and new solutions regarding intelligent transportation systems (ITS) are being requested. One solution to such is vehicle-to-vehicle communication (V2V), where safer traffic can be achieved by vehicles transmitting relevant traffic information to surrounding vehicles. In this report, we researched and developed methods for a follow-detection algorithm for V2V communication. The task was to find a solution for follow-detection by using GPS and FM-RDS, with regards to time delay. An algorithm was developed in a simulated environment, to then be implemented in a prototype for measuring traffic. For efficient usage of FM-RDS packets, the transmitted position was compressed and then decompressed at the receiving side. The results of the simulations and traffic tests indicated that it was possible to detect if a vehicle followed another in traffic, by using GPS positioning and FM-RDS with time delay. The accuracy of the algorithm degraded at higher time delays, however there is potential for improvements. Suggestions for improvements of the reconstruction function and the algorithm are discussed in this report.

  • 42.
    Saadaldin, Saif
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Bechakchyan, Annita
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Säkrad strömförsörjning av järnvägens signalsystem: Brist i ledningsreläskydd orsakade totalhaveri i Arlandas signalsystem.2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den 5 mars 2015 inträffade ett elfel i högspänningssidan av hjälpkraften mellan Häggvik och Arlanda C. Ett isolationsfel uppstod på denna sträcka, exakt mellan Upplands Väsby och Skavstaby och pågick under 18 s utan att skyddsutrustningen kopplade bort den felaktiga delen.

    Konsekvenserna blev att 22 st. kraftaggregat i Arlandas signalanläggning blev utslagna vilket orsakade totalstopp för tågtrafiken förbi Arlanda C.

    Problemet som detta examensarbete lade fokus på är varför skyddsutrustningarna inte kopplade bort elfelet snabbt och hur skyddsutrustningar samarbetar med varandra för att kunna utlösas selektivt.

    Trafikverkets övervakningssystem GELD (Gemensam Eldriftsystem) visade vilka skyddsutrustningar som var inblandade under felförloppet samt de viktigaste händelserna vid respektive tidpunkt och typ av fel. Genom att analysera data från GELD konstaterades orsaken till varför skyddsutrustningarna (jordfelsskyddet i Häggvik) inte reagerade i tid.

    För att säkerställa att inställningsvärdena för jordfelsbrytaren i Häggvik (SKBY:N) är korrekta, gjordes en teoretisk beräkning av dessa värdena.

    Resultatet blev att isolationsfelet orsakade intermittenta jordfel som medförde att jordfelsbrytarna (HGL:N) och (SKBY:N) i Häggvik inte kunde lösa ut i tid (inom 2 s) De intermittenta jordfelen har även gett överspänningar (transienter) som överbelastade de friska faserna och orsakade ytterligare jordfel på andra ställen.

    Analysen av händelserna visade att jordfelsbrytarna (HGL:N) och (SKBY:N) i Häggvik är felriktade, d.v.s. de löste ut oselektivt.

    Som åtgärd för att undvika upprepning av detta elfel bör nya kabelavslut på samtliga faser installeras. För att korrigera jordfelsbrytarnas funktion och säkerställa selektiv utlösning bör ett primärriktningsprov utföras av Trafikverket.

    En förebyggande åtgärd är att lokalisera det andra jordfelet som initierades efter det första intermittenta jordfelet.

  • 43.
    Sandberg, Johnny
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Trådlös strömning av en ljudsignal till multipla mottagare2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has examined which wireless technology that is best suited for use when an audio signal are to be streamed wirelessly to multiple recipients. The technologies that where compared was Wi-Fi and Bluetooth. Other wireless communication technologies, ZigBee, ANT+ and NFC, were excluded because their maximum data rate or range wasn’t sufficient enough. Since it’s required a license to be allowed to use 3G and 4G, these were excluded as well.  As receivers, primarily Android and iOS phones would be used. Furthermore, it has been examined which components that are required for manufacturing a prototype that will be able to stream an audio signal wireless to multiple smartphone’s. Lastly, a circuit diagram for this prototype has been made.

    Wi-Fi WLAN infrastructure was considered to be best suited for this application. The prototype that would stream an audio signal therefore needed to function as a Wi-Fi access point. AR9271, a Wi-Fi chip from Qualcomm Atheros, was selected to be used as Wi-Fi transmitter because it has an open-source firmware and were easier to come by compared to other similar Wi-Fi chip. To be able to use the Linux-based open-source firmware of the Wi-Fi chip, SAM9M10 MCU from Atmel was selected as control unit since it can be used with Linux Embedded. In order to digitize the analog audio signal, VS1063 MP3 encoder from VLSI Solution was selected.

  • 44.
    Sellrup, Jens
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Wilson, Daniel
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Tonfrekvensspårledning: S-förbindningens funktion och dimensionering av alternativa material i förbindningen2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Track circuits are used to detect where the trains are along the railway. This report contains a study of two models of audio frequency track circuit from Alstom called DTC – 921 and DTC - 24. The calculations made in the result section are made on only DTC-921. The different frequencies between two track circuits are divided by an S-bond. The S-bond is made of cupper which is a material that is theft-prone. The purpose of the project was to investigate the functionality of the S-bond and how  a cable with a different kind of material would affect the function. Three different kinds of materials have been investigated: aluminum, iron and safecable from safetrack.

     

    By studying the function of the S-bond and how it interacts with the tuning box the affect off the different materials have been evaluated. The parameters of the materials have been calculated and the function has been simulated in Pspice. 

  • 45.
    Strand, Mathias
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Standardisering av processer och aktiviteter inom kontrollanläggningar och elmontage2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis, a study has been carried out for the consulting company ÅF, and their work method within documentation and control facilities to investigate whether there were any potential for efficiency improvements. The investigation has largely involved interviews with operating consultants within the control facility on substations. The consultants worked as electrical designers and produced drawings mainly for control equipment. The results of the interviews were analyzed to draw conclusions about the efficiency potentials within the business. Different offices in the business were examined and the work approach varied between the offices. One difference was the CAD-software used and a suggestion was to use the same program. Efficiency improvement potentials were also by re-using electrical schematics to some extent from previous projects and another suggestion was to establish databases where electrical schematics can be gathered and shared between the different offices.

  • 46.
    Svensson, Johan
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Mätning av skärgradshöjd på stål2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today, a steel roll is cut within the steel industry in a cutting factory, the steel rollsare divided to smaller part bands with poor control of the burr height quality. Samplesis taken manually, the amount of samples is too low to know the quality of thesteel roll, the steel rolls can be divided up to 150 times and the length will be 30 kilometers. A whole resend for one steel roll costs up against a million SEK and has anegative climatic impact. One software prototype for detection of burr heights witha reference line was programmed. The prototype contained one light sensor, two motors,a PC and one prototype construction. Each task in the software was allocatedan own thread. Operating systems, threads and algorithms was performance testedfor measurement of execution times and period times. The result showed that a burrheight detector where possible to implement. The algorithm could detect burrheights that were too large related to its reference line.

  • 47.
    Svensson Marcial, Alexander
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Gatu, Andreas
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Justerbar modell av transmissionsledning för elkraftsöverföring2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete har utförts på uppdrag av Terco. Tercos PST 2220 Transmission Line and Distribution Module fungerar som en fysisk modell av ett verkligt transmissions- eller distributionsnät där fem olika typer av nät med avseende på längd, spänningsnivå och skenbar effekt är möjliga. Idag finns ett behov av en modell där användaren kan ställa in dessa parametrar så att modellen mer precist kan spegla vilka egenskaper det specifika nätet har. Här undersöks hur längden och dess inverkan på en ledning kan varieras i en modell. En presentation av hur transmissions- och distributionsnät fungerar och beskrivs teoretiskt lägger grunden till den modell och de två approximationer som kan beskriva ett helt näts egenskaper. Då R, L och C komponenterna behöver kunna varieras för att fysiskt kunna realisera denna teoretiska modell undersöks vilka metoder som detta kan genomföras på. För detta undersöks två tillvägagångssätt, kaskadkopplad pi-modell och variabel aktiv-passiv reaktans. Flera aspekter som utrymme, kostnad och variabilitet gör att variabel aktiv-passiv reaktans är att föredra. Dess funktion som en varierbar spänningskälla, uppbyggd av switchar styrda med reglerteknik och pulsbreddsmodulering gör att komponenterna R, L och C och dess egenskaper och inverkan på en transmissionslinje kan åstadkommas. Resultatet är att de nödvändiga R,L,C komponenterna går att variera i storlek för att kunna ingå i en varierbar transmissionsledningsmodell. Resultatet och målen säkerställs med simuleringar där variabel aktivpassiv reaktans visas kunna vidareutvecklas och praktiskt testas för att modellera transmissions- och distributionsnät med olika längd.

  • 48.
    Söderholm, Daniel
    et al.
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Fröberg, Markus
    KTH, School of Technology and Health (STH), Data- och elektroteknik.
    Energismart bevattningssystem2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Energy smart solutions are up to date and all opportunities to save energy are considered essential for protection of nature. Energy can be saved on irrigation systems by not watering if rain is approaching. By monitoring weather forecasts, the rainfall can be analyzed and irrigation adjusted accordingly.

     

    The projects goal is to create an energy smart irrigation system designed to prevent unwanted watering. By using soil moisture sensors and analyze weather data, the irrigation amount will be determined depending on the soil moisture and upcoming rainfall. Through a web page, there are configuration options and information about the system.

     

    This report explains the sensor nodes and its various functionalities in the system. The associated soil moisture sensors characteristics and its calibration are described. The water pump and its associated controlling are also treated. The system’s server and database are described as well as the link between them. There is also a flowchart of the server’s functionality. It explains how the weather data is collected and analyzed to access impending rainfall.

     

    The system's web page is shown and described with its configuration options and its status information. It also explains how the sensor motes are added, removed and edited on the website and in the system.

     

    The results summarize the work with how the different parts are linked together to form the energy smart irrigation system. An installation guide and a user manual have also been created.

  • 49.
    Villabona, Antonio
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Dietrichson, Fredrik
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Effektivisera generering av parameterfiler för betalterminaler2014Independent thesis Basic level (university diploma), 180 HE creditsStudent thesis
    Abstract [en]

    This thesis describes the process of analyzing and evaluating the structure of data storage and improving the performance for generating parameter files destined for card terminals. The work was done in house at Esplanad AB, a company dealing with security solutions and distribution of settings for payment stations.

    The first task was to evaluate the possibilities for improving the database storing the settings for each card reader. The second task was to improve the structure of the code and also improve the file generating systems performance.

    The thesis describes testing performance, both for Esplanad’s old system for generating parameter files, and the new one constructed. The solution presented includes improved performance of the file generating process and a new structure for the database that increases scalability.

    Tests show that the new system is capable of generating parameter files with TLV-format, about 16 times faster. The proposed solution implements parallel processes and database replication.

  • 50.
    Wazir, Omerjan
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Frantsalis, Ioannis
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Prestandautvärdering av Bluetooth och Wi-Fi för en smart hubb2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been carried out on behalf of the consulting company Seavus to re-duce cable usage in their office. Smart hubs (i.e. a central control unit) are made tomake usage of devices more effective.One problem is to decide between Bluetooth and Wi-Fi for communication betweenthe user and the smart hub. The choice may depend upon several factors such asbandwidth (throughput), jitter (variation in delay) and packet loss, which are im-portant parameters for assessing the quality of the communication channel.The HW-platform Raspberry Pi and compatible software was used as a measure-ment tool to test Bluetooth and Wi-Fi in different environments.The result showed that Wi-Fi is best suited for communication systems that requirehigh bandwidth and low jitter, and where high amount of packet loss is tolerable.Bluetooth is best suited for communication systems where low bandwidth and highjitter is tolerable, and minimal packet losses preferred.

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