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  • 1.
    Abbasi, Jasim Aftab
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Test of Rapid Control System Development using TargetLink2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The aim of this thesis is to employ and evaluate an evaluation board with the standard microprocessor freescale MPC5554EVB board for implementation of control algorithms which are created in Matlab/Simulink instead of using dSPACE prototyping hardware. The Simulink real-time model shall be compiled to the MPC5554EVB board. TargetLink is a powerful software tool which allows an automatic generation of efficient C code from Simulink and facilitates model-based control design. The goal of this thesis is to learn how to use TargetLink in a control design workflow from model to real code and what are the limitations of a microprocessor platform and to evaluate the capabilities of TargetLink to generate a working code for a generic microprocessor.

  • 2.
    Bergendorff, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Simuleringsmodell av tröghetsnavigator2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When time for development of new products is shortened, testing and verification must be performed at an earlier stage of development. By simulating the system, tests can be performed without access to the actual system and thus the development process can be accelerated. 

    BAE Systems Hägglunds manufacture combat vehicles and use an Inertial Navigation System (INS) to calculate the combat vehicle’s position without external references. Testing and verification of navigation with this unit in the test bench is not entirely possible. 

    The aim of this thesis is to enable realistic tests, in a test bench in the development phase, by simulating the navigator’s functions. Since communication with the Vehicle Control System (VCS) must take place in real time at the same time as navigation data must be read from external program, the model is required to have sufficient performance to provide a realistic simulation. 

    The overall question in this thesis is whether a model realized on a microcontroller (MCU) has sufficient performance to be used for simulation of an INS. To answer the question at issue, hardware for adapting the interface between the VCS, MCU and external program as well as software for simulating an INS have been created. Thereafter, the model has been verified by measuring the time for selected processes. 

    Not all functions of the navigator have been implemented in the simulation model, but the results show that the model can be used for realistic tests in the test bench.

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  • 3.
    Bergström, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Simulation Framework of embedded systems in armored vehicle design2021Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Embedded systems are a mixture of electric and mechanical hardware along with the software that is controlling them. BAE Systems Hägglunds, which designs and builds armored vehicles, is interested in knowing how to simulate these systems for logic validation and testing different design variations. 

    The goal of this thesis was to create a framework for carrying out these simulations. This was done by analyzing hardware and software design at BAE and Identifying the necessary conditions for creating a model which can be simulated.  Matlab Simulink is suggested as the tool for these simulations. The framework suggests dividing the model into smaller modules which reflects design principles at BAE. These modules will be made up of sub-modules containing hardware and software in layers. The hardware foundation will be made up of pre-designed components created in Simulink’s physical simulation library. The software will be imported into specialized sub-modules and integrated into the hardware using proposed bridge functions, converting information between the two systems.

    The framework is designed to provide a comprehensive solution instead of a deep one that can be adapted to changing circumstances. Tests have been made on small-scale systems, but the framework still needs to be tested on a large-scale system, which was not possible during this thesis. In conclusion, this is a stable foundation that needs to be built upon.  

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  • 4.
    Coenen, Bram
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    MEASURING THE REAL-TIME LATENCY OF AN I.MX7D USING XENOMAI AND THE YOCTO PROJECT2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis the real-time latency of an i.MX7D processor on a CL-SOM-IMX7 boardis evaluated. The real-time Linux for the system is created using Xenomai with both theI-Pipe patch and thePREEMPT_RTpatch. The embedded distribution is built using theYocto Project and uses a vendor i.MX kernel maintained by NXP.

    The maximum latency for thecobaltcore is268μsfor user-space tasks with a loadedCPU. These types of tasks have the highest latency of Xenomai's three task categories.A latency measurement of thePREEMPT_RTpatch showed a maximum latency ofwith an idle CPU. Therefore it is concluded that thecobalt412μscore has a lower latencyand is therefore better suited for real-time applications.

    A comparison is made with other modules and it is found that the latency measured inthis thesis is high compared to for example a Raspberry Pi 3B.

    The source code and congurations for the project can be found at https://github.com/bracoe/meta-xenomai-imx7d

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  • 5.
    Edström, Urban
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Centrum för medicinsk teknik och strålningsfysik.
    Nackvinkelmätningar vid thoraxoperation: Kan prismaglasögon underlätta arbetet för operationssjuksköterskor?2017Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
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  • 6.
    Edström, Urban
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Nackvinkelmätningar vid thoraxoperation: Kan prismaglasögon underlätta arbetet för operationssjuksköterskor?2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
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  • 7.
    Eilertsen, Svein Morten
    et al.
    Bioforsk Nord Tjøtta.
    Karlsson, Johannes
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Electronically sensors system to warn drivers if a reindeer is close to the road or the railway2014In: Nordic Association of Agricultural Scientists: NJF Report, 2014, Vol. 10, p. 30-30Conference paper (Refereed)
    Abstract [en]

    In Norway, Sweden and Finland approximately 9.000 reindeer are killed every year in traffic accidents (road and railway). In field experiments two different electronically sensor system were used. The purpose is to warn car drivers and railway engineers that reindeer are close to, or on the traffic system, and reduce the numbers of accident. The information system developed by Telespor is based on GPS/GSM radio collars. These collars use SMS to inform that the reindeer are close to the traffic system. In addition to the warning, the reindeer owners get information about the reindeer land use throughout the whole year. The collars are expensive (approx. 250 euros/unit) and need battery change every year. At Umeå University a system based on wireless sensor nodes attached to the reindeer collars is developed. This node will send out a periodic warning radio beacon. On road sticks a warning device will be attached containing a radio receiver and LED flashlights that will warn if a radio beacon is received. To further increase the warning distance it is possible to use communication between the roadside warning devices and let several devices flash their LED lights when a reindeer is detected. The radio collar (approx. 15 euros/unit) will have a theoretical battery life of more than 10 years. The radio range is around 500 meters between the radio collar and the roadside warning device, which is more than sufficient.

  • 8.
    Ekvall, Malkolm
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    LiDAR som analysverktyg vid brunnsinspektion2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The use of LiDAR (Light Detection And Ranging) for inspection of manholes is a rather unexplored field. This bachelor thesis explains the basics of LiDAR and investigate possible uses for LiDAR in analysis and inspection of manholes. The use of LiDAR to investigate the depth of water, surface level of the water and 3D-modeling with point clouds of the inside are the three points this thesis investigate. This is achieved through the usage of three different LiDAR units. Two of these units are used for detecting the depth and surface level of water. One of these units is connected to an Arduino Uno which in turn is transmitting data to MATLAB for data processing. The other LiDAR unit is connected to a Raspberry Pi and communicate through Modbus. A program written in Python collects and process the data. The third LiDAR unit is used for collecting point cloud data. This LiDAR rotates in 360 degrees and collect two dimensional data. The LiDAR unit is then moved in a third dimension for enabling third dimensional data collection. This unit is in turn connected to a Raspberry Pi where a program written in Python is used for data processing.Detecting the water depth is hard and fails cause of technical limitations. It does however work for detecting the water level. 3D point clouds are made with plotting of point cloud data. None of the two LiDAR units used for detecting water depth is recommended cause of technical limitations. The two LiDAR units used for detecting the water level are both viable choices. The 3D point cloud can be used as a complement for analysis of manholes. This thesis is done in collaboration with Omicron Ceti AB.

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    LiDAR som analysverktyg vid brunnsinspektion
  • 9.
    El-Tai, Jaffar
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Implementation av ny ARM Cortex-M mikrokontroller i QEMU2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Through emulation of hardware, development can be achieved prior to receiving said hardware.With that, the development process will accelerate.

    The purpose of the thesis is to adapt an emulator for proprietary hardware modules at Cytiva. Towork with hardware during development and testing has some disadvantages. Among other things,the hardware costs money to manufacture and it can take a long time to order and manufacturenew components. Due to this, an emulation solution will be tested for the proprietary hardwaremodels at the company.

    The implementation of the emulated microcontroller lacks some functionality. Among other things,there is no GIPO implementation to be able to send and receive test stimuli. This is due to, amongother things, lack of time. Although, a simple ”Hello World” test program was implemented thatprints to the terminal via USART. This test program shows that the emulated microcontroller andits peripherals are working as intended.   

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  • 10.
    Forsgren, Fredrik
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Active Noise Control in Forest Machines2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Achieving a low noise level is of great interest to the forest machine industry. Traditionally this is obtained by using passive noise reduction, i.e. by using materials for sound isolation and sound absorption. Especially designs to attenuate low frequency noise tend to be bulky and impractical from an installation point of view. An alternative solution to the problem is to use active noise control (ANC). The basic principle of ANC is to generate an anti-noise signal designed to destructively interfere with the unwanted noise.

    In this thesis two algorithms (Feedback FxLMS and Feedforward FxLMS) are implemented and evaluated for use in the ANC-system. The ANC-system is tuned to the specific environment in the driver’s cabin of a Komatsu forest machine. The algorithms are first tested in a simulated environment and then in real-time inside a forest machine.

    Simulations are made both in Matlab and in C using both generated signals and recorded signals. The C code is implemented on the Analog Devices Blackfin DSP card BF526.

    The result showed a significantly reduction of the sound pressure level (SPL) in the driver’s cabin. The noise attenuation obtained using the Feedback FxLMS was approximately 14 dB for a tonal 100 Hz signal and 11 dB using recorded engine noise from a forest machine at 850 rpm.

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  • 11.
    Hedenström, Pontus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Utveckling och utvärdering av lågkostnadssystem för inklinationsmätning på fordon2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This student thesis is carried out togheter with Ålö AB which manufactures front loaders under the Quicke brand and intents to evaluate a system that calculates vehicle incline. The system should prioritize low cost and must use electronics that is classified for vehicle use (AEC-Q100). This thesis deals with selecting components, sensors and motivations of the selected components, theory of sensor signal conditioning in noisy environments and its implementation.

     

    Two sensors where selected that was deemed suitable for evaluation. The first was a 3-axis accelerometer for which a proprietary 2D-positioning algorithm was used to calculate incline. The second sensor that was chosen was a 6-axis IMU that was implemented using sensor fusion with a Kalman filter which was realized with an available software library. The system hardware was implemented with a custom PCB.

     

    The system was tested and evaluated stationary and, on a vehicle, along with a reference sensor to give an indication of how the sensors and their respective algorithms performed in both ideal and a real conditions. The stationary tests showed that both solutions perform well regarding outputting incline close to the actual angle. The reliability of the vehicle tests can be improved and as the results they yielded are not of high enough quality to draw conclusions from them. This leads to a recommendation of further testing and evaluation of both solutions.

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  • 12.
    Ibrahim, Omar
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    SIGNALBEHANDLING MED AVANCERAD BLUETOOTH-TEKNIK OCH OPTIMERADE OPERATIVSYSTEM: Optimera audiosystemet i ett avancerat inbyggt system med en fler-trådad programvara och synkroniserings mekanism2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study is about replacing an old bluetooth module with a new variant, namely the BM83 which is an integrated circuit that contains an internal DSP circuit, profiles and important functions such as noise reduction, acoustic echo removal and EQ filtering. The purpose of this study is to replace the old module with the BM83, as well as explore the internal DSP circuit in the BM83. The goal is to develop the audio system with a high performance bluetooth and explore the BM83's built-in DSP functions and its profiles to optimize sound quality. This study takes different methods and performs different experiments to test the ability of BM83 to replace RN52 in a DSP platform. In addition, it was proposed that an audiosystem should be managed in an operating system with the idea of optimizing data transfer by using some of new operating system mechanism methods. In this study, the differences between BM83 and RN52 were discussed in terms of their profiles, built-in CODEC and DSP algorithm.This study provides how SPP, A2DP and HFP can be used together when the BM83 is controlled by a DSP platform. In addition, it was tested how A2DP and HFP have a great importance in providing events that a DSP platform can decide on and how it chooses its source depending on these events. In addition, the data communication between the BM83 and an STM32F7 was tested via the SPP protocol, with the idea that any data would be sent and received via SPP without loss in data transmission. In conclusion, it was discussed what type of data communication is used between BM83 and an MCU in comparison between RN52 and how the built-in DSP circuit and itsprofiles are important for future research. This project was funded by the Hearing Research Foundation in project FA21-0017 and was carried out under the supervision of Amin Saremi. 

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  • 13.
    Jiang, Zhe
    et al.
    Southeast University, Nanjing, China.
    Dai, Xiaotian
    University of York, United Kingdom.
    Wei, Ran
    University of Cambridge, United Kingdom.
    Gray, Ian
    University of York, United Kingdom.
    Gu, Zonghua
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Zhao, Qingling
    Nanjing University of Science and Technology, China.
    Zhao, Shuai
    Sun Yat-sen University, China.
    NPRC-I/O: a NoC-based real-time I/O system with reduced contention and enhanced predictability2023In: IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, ISSN 0278-0070, E-ISSN 1937-4151, p. 1-1Article in journal (Refereed)
    Abstract [en]

    All systems rely on inputs and outputs (I/Os) to perceive and interact with their surroundings. In safety-critical systems, it is important to guarantee both the performance and time-predictability of I/O operations. However, with the continued growth of architectural complexity in modern safety-critical systems, satisfying such real-time requirements has become increasingly challenging due to complex I/O transaction paths and extensive hardware contention. In this paper, we present a new NoC-based Predictable I/O system framework (NPRC-I/O) which reduces this contention and ensures the performance and timepredictability of I/O operations. Specifically, NPRC-I/O contains a programmable I/O command controller (NPRC-CC) and a runtime reconfigurable NoC (RNoC), which provides the capability to adjust I/O transaction paths at run-time. Using this flexibility, we construct an end-to-end transmission latency analysis and an optimisation engine that produces configurations for NPRCI/ O and the I/O traffic in a given system. The constructed analysis and optimisation engine guarantee the timing of all hard realtime traffic while reducing the deadline misses of soft real-time traffic and overall transmission latency.

  • 14.
    Jorda, Andrei
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Automatisk mikrofonmixer2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
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  • 15.
    Karlsson, Johannes
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Low-Complexity Encoding in Block-Based Hybrid Video Codecs by Moving Motion Estimation to Decoder Side2014In: International Journal of Adaptive, Resilient and Autonomic Systems, ISSN 1947-9220, E-ISSN 1947-9239, Vol. 5, no 1, p. 19-29Article in journal (Refereed)
    Abstract [en]

    In this paper the authors present an approach to provide efficient low-complexity encoding for the block-based video coding scheme. The authors present a method based on removing the most time-consuming task, that is motion estimation, from the encoder. Instead the decoder will perform motion prediction based on the available decoded frame and send the predicted motion vectors to the encoder. The results presented are based on a modified H.264 implementation. The results show that this approach can provide rather good coding efficiency even for relatively high network delays.

  • 16.
    Karlsson, Johannes
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Motion estimation on decoder side for low-complexity video encoding in wireless sensor networks2012In: 1st International Workshop on Wireless Multimedia Sensor Networks (WMSN'12),Barcelona, Spain, October 8-10, 2012, IEEE Computer Society, 2012Conference paper (Refereed)
  • 17.
    Karlsson, Johannes
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Two hop connectivity for uniformed randomly distributed points in the unit square2012In: International Journal of Wireless & Mobile Networks, ISSN 0975-4679, E-ISSN 0975-3834, Vol. 4, no 4, p. 1-12Article in journal (Refereed)
  • 18.
    Lind, Filip
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Inomhuspositionering av djur med hjälp av UWB-teknik och triangulering2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The project was about creating a Real Time Location System for indoor positioning of animals. The system uses Ultra-Wideband technology to measure distance to a number of base stations placed in an area around moving nodes which are going to be positioned. For positioning, triangulation is used. The project is about individually tracking each animal to optimize their breeding. The goal of the project is to finish a working system for testing in Sveriges lantbruksuniversitet’s research barn at Röbäck, Umeå, in the beginning of the summer. To create a complete system, source code from a product named TREK1000, by the Irish company DecaWave, has been ported to the decided modules. That can be done because TREK1000 is preforming the same task which this project is aiming to do. To preserve the applications functionality, only the platform-specific code needs to be changed.

    The project resulted in a working system for distance calculation between the Ultra-Wideband nodes. The ranging have a measured accuracy of +/- 30 centimeters which is really great compared to other alternatives. Only home testing is done so far and no testing of the system in the barn has been done yet. The hopes are that the same accuracy can be accomplished there. However, the final real time system for positioning is not working correctly since the positions of the nodes cannot be shown in the application. This application could later be extended to other applications other than animals, since it can be interesting to determine the position of other moving objects in other places. 

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    Inomhuspositionering av djur med hjälp av UWB-teknik och triangulering
  • 19.
    Lovén, Jimmy
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Prototyputveckling av USB-växel2013Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
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  • 20.
    Lu, Zhihan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. SIAT, Chinese Academy of Science, China.
    ur Rehman, Shafiq
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. SIAT, Chinese Academy of Science, China.
    Multi-Gesture based Football Game in Smart Phones2013In: SA '13 SIGGRAPH Asia 2013 Symposium on Mobile Graphics and Interactive Applications, NY, USA: Association for Computing Machinery (ACM), 2013Conference paper (Refereed)
  • 21.
    Lu, Zhihan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    ur Réhman, Shafiq
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Touch-less interaction smartphone on go!2013In: Proceeding of SIGGRAPH Asia 2013, ACM New York, NY, USA, 2013Conference paper (Refereed)
    Abstract [en]

    A smartphone touch-less interaction based on mixed hardware and software is proposed in this work. The software application renders circle menu application graphics and status information using smart phone’s screen, audio. Augmented reality image rendering technology is employed for a convenient finger-phone interaction. The users interact with the application using finger gesture motion behind the camera, which trigger the interaction event and generate activity sequences for interactive buffers. The combination of Contour based Template Matching (CTM) and Tracking-Learning-Detection (TLD) provides a core support for hand-gesture interaction by accurately detecting and tracking the hand gesture.

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  • 22.
    Lu, Zhihan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    ur Réhman, Shafiq
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Chen, Ge
    Ocean University of China, Qingdao, China.
    WebVRGIS: WebGIS based interactive online 3D virtual community2013In: 2013 International Conference on Virtual Reality and Visualization (ICVRV 2013), Institute of Electrical and Electronics Engineers (IEEE), 2013, p. 94-99Conference paper (Refereed)
    Abstract [en]

    In this paper we present a WebVRGIS based Interactive Online 3D Virtual Community which is achieved based on WebGIS technology and web VR technology. It is Multi-Dimensional(MD) web geographic information system (WebGIS) based 3D interactive online virtual community which is a virtual real-time 3D communication systems and web systems development platform. It is capable of running on a variety of browsers. In this work, four key issues are studied: (1) Multi-source MD geographical data fusion of the WebGIS, (2) scene combination with 3D avatar, (3) massive data network dispatch, and (4) multi-user avatar real-time interactive. Our system is divided into three modules: data preprocessing, background management and front end user interaction. The core of the front interaction module is packaged in the MD map expression engine 3GWebMapper and the free plug-in network 3D rendering engine WebFlashVR. We have evaluated the robustness of our system on three campus of Ocean University of China(OUC) as a testing base. The results shows high efficiency, easy to use and robustness of our system.

  • 23.
    Lu, Zhihan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    ur Réhman, Shafiq
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Khan, Muhammad Sikandar Lal
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Li, Haibo
    Royal Institute of Technology (KTH), Sweden..
    Anaglyph 3D stereoscopic visualization of 2D video based on fundamental matrix2013In: Proceedings of 2013 International Conferenceon Virtual Reality and Visualization (ICVRV 2013), 14-15 September 2013, Xi'an, Shaanxi, China, 2013Conference paper (Refereed)
    Abstract [en]

    In this paper, we propose a simple Anaglyph 3Dstereo generation algorithm from 2D video sequence with monocularcamera. In our novel approach we employ camera poseestimation method to directly generate stereoscopic 3D from 2Dvideo without building depth map explicitly. Our cost effectivemethod is suitable for arbitrary real-world video sequence andproduces smooth results. We use image stitching based on planecorrespondence using fundamental matrix. To this end we alsodemonstrate that correspondence plane image stitching based onHomography matrix only cannot generate better result. Furthermore,we utilize the structure from motion (with fundamentalmatrix) based reconstructed camera pose model to accomplishvisual anaglyph 3D illusion. The proposed approach demonstratesa very good performance for most of the video sequences.

  • 24.
    Mikkelsen, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Development, Modelling and Control of a Multirotor Vehicle2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The interest of drones in all forms has exploded in the recent years. The development of multirotor vehicles such as quadcopters and octocopters, has reached a point where they are cheap and versatile enough to start becoming a part of everyday life. It is clear to say that the future applications seem limitless. This thesis goes through the steps of development, modelling and control design of an octocopter system. The developed octocopter builds on a concept of using the mini computer Raspberry Pi together with the code generation functionality of Matlab/Simulink. The mathematical modelling of the octocopter includes the thrust and torques generated by the propellers, added with gyroscopic torque. These are combined with the aerodynamic effects caused by incoming air. The importance of modelling the later mentioned effects has increased with the demand of precise controlled extreme manoeuvres. A full state feedback based hybrid controller scheme is designed against a linearized model, which makes use of the motor dynamics. The controllers show good performance in simulations and are approved for flight tests, which are conducted on two separate occasions. The octocopter makes two successful flights, proving that the concept can be applied on multirotor vehicles. However, there is a miss-match between the mathematical model and the physical octocopter, leaving questions for future work.

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    DevelopmentModellingAndControlOfAMultirotorVehicle
  • 25.
    Olofsson, Petter
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Utterström, Jimmy
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Hydraulstyrning med konfiguration över Bluetooth2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report encompasses the development of a standalone drive card with an accompanying mobile application for control and configuration of a hydraulic system. The purpose of the project was to - according to an inquiry from the client Bosch Rexroth - investigate whether the pump control module (PCM) from the existing Spider 3 control system could be used as a standalone module. Hardware including a Bluetooth module was assembled and connected to the PCM to allow communication over Bluetooth Low Energy (BLE). A mobile application where developed in Android Studio to allow configuration from a mobile device. The software of the PCM were modified to communicate with the Bluetooth hardware over CAN and also for allowing analog control of the hydraulic pump through a current controlled input.The basic demands for the system were met and a working prototype could be demonstrated at the end of the project. The prototype did show large potential but was lacking some functionality which would be desirable for a commercial product.

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  • 26.
    Olsson, Alexander
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Meshnetwork of wireless IoT sensors2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Internet of things is a scenario where devices such as lighting, household appliances, sensors etc. are connected and communicate with each other via Internet. This puts a demand for a good infrastructure around these devices. One way to handle this is to use radio as a means of communication and let the devices forward each other's traffic in what is known as a mesh network.

    This thesis explores different radio standards that can be used to create a mesh network for sensors. Two different approaches to mesh networking using Bluetooth Low Energy was implemented and evaluated. One approach works by letting all devices broadcast every message they receive, a rather brute force approach. The other approach worked by letting the network find routes between all the nodes in the network and then establishes a connection between the nodes that want to communicate via intermediate nodes.

    It was found that the rebroadcast approach in idle mode used 3.36 mAh while the connection approach used 0.47 mAh for the same configuration. Another test was performed where the percentage of successfully delivered messages was measured. For the rebroadcast approach it was 75 % and for connection it was 58 %. Tweaking the connection network to not be able to adapt to changes increased the throughput to 77 %.

    During the testing numerous ways for improving performance were thought of but not implemented. The need for synchronizing the devices clocks and establishing protocol for when to send and receive became apparent when working with the rebroadcast network. In the connection network there were problems with that the routing maintenance led to unavailable units and reduced performance.

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  • 27.
    Oscar, Eriksson Janze
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Design of auxiliary communication for audio between computers and DSPs: Programming and optimization of computational resources2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis report is about designing a prototype and establishing audio communication between a computer and Digital Signal Processor (DSP) using two preamp circuits using both auxiliary and USB connection. The paper gives the reader an overview on how audio is transmitted from a computer, through the system and to the desired output. The reader should also get a better understanding of how an AD-converter samples the incoming signal to the Discrete plane and how an AUX or phone connector works. This information can be used for designing preamp circuits to communicate between a computer and the DSP. The DSP circuit uses an STM32 processor to control the incoming and outgoing signals with the use of ADC and DAC conversion. The DSP also uses microphones to capture surrounding sound. An addition is to make a prototype on how to use these microphones to  send the signal upstream to the computer. The microphone is then benchmarked with the use of Matlab, calculating Total Harmonic Distortion. Management and optimization of code structure and resources is done in the source files of the project. Using imperative C programing, large functions are broken down into smaller functions to ease readability and control flow. The result is a prototype circuit that can communicate audio signals with both audio jack and USB between computers input and output to the DSP. Using CubeMX in conjunction with CubeIDE to add additional ADC channels to be able to incorporate an automatic source control when the audio jack or USB is connected.

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  • 28.
    Pérez Rodríguez, Arturo
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Quadcopter stabilization based on IMU and Monocamera Fusion2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Unmanned aerial vehicles (UAVs), commonly known as drones, have revolutionized numerous fields ranging from aerial photography to surveillance and logistics. Achieving stable flight is essential for their successful operation, ensuring accurate data acquisition, reliable manoeuvring, and safe operation. This thesis explores the feasibility of employing a frontal mono camera and sensor fusion techniques to enhance drone stability during flight. The objective of this research is to investigate whether a frontal mono camera, combined with sensor fusion algorithms, can be used to effectively stabilize a drone in various flight scenarios. By leveraging machine vision techniques and integrating data from onboard gyroscopes, the proposed approach aims to provide real-time feedback for controlling the drone. The methodology for this study involves the Crazyflie 2.1 drone platform equipped with a frontal camera and an Inertial Measurement Unit (IMU). The drone’s flight data, including position, orientation, and velocity, is continuously monitored and analyzed using Kalman Filter (KF). This algorithm processes the data from the camera and the IMU to estimate the drone’s state accurately. Based on these estimates, corrective commands are generated and sent to the drone’s control system to maintain stability. To evaluate the effectiveness of the proposed system, a series of flight tests are conducted under different environmental conditions and flight manoeuvres. Performance metrics such as drift, level of oscillations, and overall flight stability are analyzed and compared against baseline experiments with conventional stabilization methods. Additional simulated tests are carried out to study the effect of the communication delay. The expected outcomes of this research will contribute to the advancement of drone stability systems. If successful, the implementation of a frontal camera and sensor fusion can provide a cost-effective and lightweight solution for stabilizing drones.

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  • 29.
    Rabiee, Ramtin
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Karlsson, Johannes
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Multi-Bernoulli Tracking Approach for Occupancy Monitoring of Smart Buildings Using Low-Resolution Infrared Sensor Array2021In: Remote Sensing, E-ISSN 2072-4292, Vol. 13, no 16, article id 3127Article in journal (Refereed)
    Abstract [en]

    Knowledge about the indoor occupancy is one of the important sources of information to design smart buildings. In some applications, the number of occupants in each zone is required. However, there are many challenges such as user privacy, communication limit, and sensor’s computational capability in development of the occupancy monitoring systems. In this work, a people flow counting algorithm has been developed which uses low-resolution thermal images to avoid any privacy concern. Moreover, the proposed scheme is designed to be applicable for wireless sensor networks based on the internet-of-things platform. Simple low-complexity image processing techniques are considered to detect possible objects in sensor’s field of view. To tackle the noisy detection measurements, a multi-Bernoulli target tracking approach is used to track and finally to count the number of people passing the area of interest in different directions. Based on the sensor node’s processing capability, one can consider either a centralized or a full in situ people flow counting system. By performing the tracking part either in sensor node or in a fusion center, there would be a trade off between the computational complexity and the transmission rate. Therefore, the developed system can be performed in a wide range of applications with different processing and transmission constraints. The accuracy and robustness of the proposed method are also evaluated with real measurements from different conducted trials and open-source dataset.

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  • 30.
    Ren, Keni
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Zoom in on the precision livestock farming2021Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Global attention to the welfare of zoo animals and livestock results in stronger legislation and higher pressure for achieving higher standards of animal welfare. Monitoring and understanding animal behaviour can assist in optimising the welfare of zoo and livestock animals. Precision livestock farming solutions open the door to increase automation of behaviour monitoring and welfare management. The overall purpose of the thesis was to investigate the possibilities of using computer vision and sensor technology for studying animal behaviour in zoo and production environments. To fulfil this overall purpose, two main research questions were addressed: How can we identify and track individual animals using computer vision and sensor technology? Combining the identity and position information, how well animal behaviour can be monitored and analysed?

    First, we developed and justified methods for identifying and tracking individual animals in different livestock environments: zoo outdoor environment, sheep barn and free-stall dairy cattle barn's indoor production environment. Three methods were developed to identify and track individual animals: a combination of radio frequency identification and camera sensor, a deep learning method based on visual biometrics and behaviour features and an ultra-wideband based real-time location system method. The data quality, in terms of missing data, in one commercially available ultra-wideband system was examined. The choice of method was justified according to different species' natural appearance, breeding strategy and housing conditions. We found that the computer vision system can perform as good as an expert in identifying individual bears based on images. The real-time location system can provide the position of individual animals inside barns with a mean error under 0.4 m. No major obstacles were found to interfere with the ultra-wideband based real-time location system. The between-cow variation was statistically significant.

    Second, two animal behaviour monitoring systems that assist activity registration and analysing social interactions were proposed. To detect sheep's standing and lying behaviour in sheep barn environments, infrared radiation cameras, and three-dimensional computer vision technology were used. Dairy cows' negative and positive social interactions were analysed using a Long-term Recurrent Convolution Networks model. Both systems integrated the real-time location system and computer vision system to perform identification, tracking and analysing animal behaviour tasks. Working with real systems in a real-world application setting made the study more credible and valuable for the related research. The result showed that the system was able to understand animal standing lying activity and social behaviour.

    The developed technologies and the results of the experiments added value for the animal behaviour monitoring by focusing on individual or sub-group in a herd and analysing individual activity and social behaviour continuously. By understanding animal behaviour, it can push the continuous surveillance system towards a welfare decision support system.

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  • 31.
    Ren, Keni
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Karlsson, Johannes
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Animal Tracking in Multi-Modal Wireless Sensor Networks2012In: SNCNW 2012 ( the 8th Swedish National Computer Networking Workshop), June 7-8, 2012, 2012Conference paper (Refereed)
  • 32.
    Ren, Keni
    et al.
    Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Nielsen, Per Peetz
    Alam, Moudud
    Rönnegård, Lars
    Where do we find missing data in a commercial real-time location system?: Evidence from 2 dairy farms2021In: JDS Communications, ISSN 2666-9102, Vol. 2, no 6, p. 345-350Article in journal (Refereed)
    Abstract [en]

    Real-time indoor positioning using ultra-wideband devices provides an opportunity for modern dairy farms to monitor the behavior of individual cows; however, missing data from these devices hinders reliable continuous monitoring and analysis of animal movement and social behavior. The objective of this study was to examine the data quality, in terms of missing data, in one commercially available ultra-wideband–based real-time location system for dairy cows. The focus was on detecting major obstacles, or sections, inside open freestall barns that resulted in increased levels of missing data. The study was conducted on 2 dairy farms with an existing commercial real-time location system. Position data were recorded for 6 full days from 69 cows on farm 1 and from 59 cows on farm 2. These data were used in subsequent analyses to determine the locations within the dairy barns where position data were missing for individual cows. The proportions of missing data were found to be evenly distributed within the 2 barns after fitting a linear mixed model with spatial smoothing to logit-transformed proportions (mean = 18% vs. 4% missing data for farm 1 and farm 2, respectively), with the exception of larger proportions of missing data along one of the walls on both farms. On farm 1, the variation between individual tags was large (range: 9–49%) compared with farm 2 (range: 12–38%). This greater individual variation of proportions of missing data indicates a potential problem with the individual tag, such as a battery malfunction or tag placement issue. Further research is needed to guide researchers in identifying problems relating to data capture problems in real-time monitoring systems on dairy farms. This is especially important when undertaking detailed analyses of animal movement and social interactions between animals.

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  • 33.
    Rezk, Nesma
    et al.
    Halmstad University.
    Purnaprajna, Madhura
    Amrita School of Engineering: Bangalore, Karnataka, India.
    Nordström, Tomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Ul-Abdin, Zain
    Halmstad University.
    Recurrent Neural Networks: An Embedded Computing Perspective2020In: IEEE Access, E-ISSN 2169-3536, Vol. 81, no 1, p. 57967-57996Article in journal (Refereed)
    Abstract [en]

    Recurrent Neural Networks (RNNs) are a class of machine learning algorithms used for applications with time-series and sequential data. Recently, there has been a strong interest in executing RNNs on embedded devices. However, difficulties have arisen because RNN requires high computational capability and a large memory space. In this paper, we review existing implementations of RNN models on embedded platforms and discuss the methods adopted to overcome the limitations of embedded systems. We will define the objectives of mapping RNN algorithms on embedded platforms and the challenges facing their realization. Then, we explain the components of RNN models from an implementation perspective. We also discuss the optimizations applied to RNNs to run efficiently on embedded platforms. Finally, we compare the defined objectives with the implementations and highlight some open research questions and aspects currently not addressed for embedded RNNs. Overall, applying algorithmic optimizations to RNN models and decreasing the memory access overhead is vital to obtain high efficiency. To further increase the implementation efficiency, we point up the more promising optimizations that could be applied in future research. Additionally, this article observes that high performance has been targeted by many implementations, while flexibility has, as yet, been attempted less often. Thus, the article provides some guidelines for RNN hardware designers to support flexibility in a better manner.

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  • 34.
    Sandström, Joakim
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Utveckling av sensorbaserat system för personräkning i inomhusmiljö2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this work, a system is being developed with the purpose of counting people. The system is intended for use in meeting rooms for up to ten persons and utilizes infrared technique using thermopile arrays. For this work, three different sensor have been used for evaluation. A Panasonic Grid-EYE with a resolution of 8×8 and a Field of View (FoV) of 60°×60°, and two Heimann 32×32d sensors, both having a resolution of 32×32, but with the FoV 90°×90° and 105°×105° respectively. The system has been programmed using the microcontroller STM32L476RG, and with the programming language C. In this system, two methods for people counting has been implemented. The first method compares the total change in temperature of a room in relation to when the room is empty and the other method uses image processing methods, such as interpolation, filtering and area calculations. The sensors are also being evaluated individually, based on characteristics such as accuracy, current consumption and implementation cost. To graphically display the temperature values of the sensors, scripts has been made for MATLAB that uses information sent by the microcontroller. The sensor which seem to be best suited for counting people is the Heimann 32×32d with the FoV 105°×105°. The main advantage of this sensor is its wider FoV, covering a larger area, and its higher resolution, which overall yields a higher accuracy when counting people. However, this sensor requires more complex and time-consuming calculations when processing data than the Grid-EYE. Still, these differences are marginal where the accuracy and the larger detectable area for the HTPA outweighs its disadvantages. The experimental results shows that the Heimann sensor with 105°×105° FoV can achieve an accuracy of ≈98.3 % measuring at a height of 2.45 m. At this height, the detectable area for the sensor is ≈39.1 m2 and is being able to count up to at least 4 persons. As for the Grid-EYE and with the same scenario, the accuracy has not been determined, but has a detectable area of ≈7.7 m2 and is estimated being able to count up to a maximum of 4 persons.

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  • 35.
    Saremi, Amin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Spatial audio signal processing for speech telecommunication inside vehicles2022In: Advances in fundamental and applied research on spatial audio / [ed] Brian F.G. Katz; Piotr Majdak, London: InTech, 2022, p. 175-192Chapter in book (Refereed)
    Abstract [en]

    Since the introduction of hands-free telephony applications and speech dialog systems in automotive industry in 1990s, microphones have been mounted in car cabins to capture, and route the driver's speech signals to the corresponding telecommunication networks. A car cabin is a noisy and reverberant environment where engine activity, structural vibrations, road bumps, and cross-talk interferences can add substantial amounts of acoustic noise to the captured speech signal. To enhance the speech signal, a variety of real-time signal enhancement methods such as acoustic echo cancellation, noise reduction, de-reverberation, and beamforming are typically applied. Moreover, the recent introduction of AI-driven online voice assistants in automotive industry has resulted in new requirements on speech signal enhancement methods to facilitate accurate speech recognition. In this chapter, we focus on spatial filtering techniques that are designed to spatially enhance signals that arrive from certain directions while attenuating signals that originate from other locations. The fundamentals of conventional beamforming and echo cancelation are explained and are accompanied by some real-world examples. Moreover, more recent techniques (namely blind source segregation, and neural-network based adaptive beamforming) are presented in the context of automotive applications. This chapter provides the readers with both fundamental and hands-on insights into the fast-growing field of automotive speech signal processing.

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  • 36.
    Savas, Süleyman
    et al.
    School of Information Technology, Halmstad University, Halmstad, Sweden; Department of Computers Science, Lund University, Lund, Sweden.
    Ul-Abdin, Zain
    School of Information Technology, Halmstad University, Halmstad, Sweden.
    Nordström, Tomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    A framework to generate domain-specific manycore architectures from dataflow programs2020In: Microprocessors and microsystems, ISSN 0141-9331, E-ISSN 1872-9436, Vol. 72, article id 102908Article in journal (Refereed)
    Abstract [en]

    In the last 15 years we have seen, as a response to power and thermal limits for current chip technologies, an explosion in the use of multiple and even many computer cores on a single chip. But now, to further improve performance and energy efficiency, when there are potentially hundreds of computing cores on a chip, we see a need for a specialization of individual cores and the development of heterogeneous manycore computer architectures.

    However, developing such heterogeneous architectures is a significant challenge. Therefore, we propose a design method to generate domain specific manycore architectures based on RISC-V instruction set architecture and automate the main steps of this method with software tools. The design method allows generation of manycore architectures with different configurations including core augmentation through instruction extensions and custom accelerators. The method starts from developing applications in a high-level dataflow language and ends by generating synthesizable Verilog code and cycle accurate emulator for the generated architecture.

    We evaluate the design method and the software tools by generating several architectures specialized for two different applications and measure their performance and hardware resource usages. Our results show that the design method can be used to generate specialized manycore architectures targeting applications from different domains. The specialized architectures show at least 3 to 4 times better performance than the general purpose counterparts. In certain cases, replacing general purpose components with specialized components saves hardware resources. Automating the method increases the speed of architecture development and facilitates the design space exploration of manycore architectures.

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  • 37.
    Shafiq, ur Réhman
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Li, Haibo
    Royal Institute of Technology (KTH), Sweden..
    Using Vibrotactile Language for Multimodal Human Animals Communication and Interaction2014In: Proceedings of the 2014 Workshops on Advances in Computer Entertainment Conference, ACE '14, Association for Computing Machinery (ACM), 2014, p. 1:1-1:5Conference paper (Refereed)
    Abstract [en]

    In this work we aim to facilitate computer mediated multimodal communication and interaction between human and animal based on vibrotactile stimuli. To study and influence the behavior of animals, usually researchers use 2D/3D visual stimuli. However we use vibrotactile pattern based language which provides the opportunity to communicate and interact with animals. We have performed experiment with a vibrotactile based human-animal multimodal communication system to study the effectiveness of vibratory stimuli applied to the animal skin along with audio and visual stimuli. The preliminary results are encouraging and indicate that low-resolution tactual displays are effective in transmitting information.

  • 38.
    Stymne, Petter
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Säkerhetskritiska standarder och FPGA2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    IEC 61508, ISO 26262, DO-254 och CENELEC EN 5012x är alla standarder för utveckling av säkerhetskritiska system. Dessa fyra är applicerbara på bilar upp till 3.5 ton (ISO 26262), flyg (DO-254), tåg (Cenelec EN 5012x) samt IEC 61508 vilket är en standard för flertalet industrigrenar.

    När ett säkerhetskritiskt system skall implementeras i en FPGA så kan problem uppstå. Detta för att en FPGA ibland räknas till hårdvara men utvecklingen följer samma mönster som mjukvaruutveckling. Detta examensarbetes huvuduppgift är att klargöra hur de olika standarderna ser på FPGA utveckling samt verifiering med hjälp av utökad funktionell verifiering.

    Uppsatsen är uppdelad i två delar. Den första delen behandlar de säkerhetskritiska standarderna. Vi kommer att gå igenom dessa för att få en översikt samt visa vilka skillnader likheter som finns. Hur ställer de sig till FPGA, hårdvara eller mjukvara.

    Del två går igenom ett projekt i enlighet med IEC 61508, inklusive metoder för funktionell verifiering ingå. Dessa metoder är ABV (Assertion Based Verification) samt täckningsgrad för verifieringen. Har vi verifierat tillräckligt och vilka krav ställs på ett projekt enligt IEC 61508. I den här delen går vi även igenom hur de olika standarderna ser på FPGA:er samt några rekommendationer gällande FPGA utveckling och säkerhetskritiska system.

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  • 39.
    Stymne, Petter
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Säkerhetskritiska standarder och FPGA2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    IEC 61508, ISO 26262, DO-254 och CENELEC EN 5012x är alla standarder för utveckling av säkerhetskritiska system. Dessa fyra är applicerbara på bilar upp till 3.5 ton (ISO 26262), flyg (DO-254), tåg (Cenelec EN 5012x) samt IEC 61508 vilket är en standard för flertalet industrigrenar.

    När ett säkerhetskritiskt system skall implementeras i en FPGA så kan problem uppstå. Detta för att en FPGA ibland räknas till hårdvara men utvecklingen följer samma mönster som mjukvaruutveckling. Detta examensarbetes huvuduppgift är att klargöra hur de olika standarderna ser på FPGA utveckling samt verifiering med hjälp av utökad funktionell verifiering.

    Uppsatsen är uppdelad i två delar. Den första delen behandlar de säkerhetskritiska standarderna. Vi kommer att gå igenom dessa för att få en översikt samt visa vilka skillnader likheter som finns. Hur ställer de sig till FPGA, hårdvara eller mjukvara.

    Del två går igenom ett projekt i enlighet med IEC 61508, inklusive metoder för funktionell verifiering ingå. Dessa metoder är ABV (Assertion Based Verification) samt täckningsgrad för verifieringen. Har vi verifierat tillräckligt och vilka krav ställs på ett projekt enligt IEC 61508. I den här delen går vi även igenom hur de olika standarderna ser på FPGA:er samt några rekommendationer gällande FPGA utveckling och säkerhetskritiska system.

  • 40.
    Sundh, Roger
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Generellt mät- och styrsystem2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis work was to create a general measurement and control system, which is remotely controlled using Internet. The system comprises a controlling computer and several separate modules, each one realizing one or more measurement and control tasks. The possibilities of such a system are wide. It could be used for home automation, industrial process control or by the entertainment business. For example, the system can implement measurement of temperature, distance, pressure and light and control servos, lamps and general digital outputs.A fully implemented system comprises over 100 separate modules, so for practical reasons this thesis work was restricted to only implementing and demonstrating a few of those modules. Since the system is easily scalable, this was a minor restriction, which did not negatively affect the results.The results show that the system works and in general the latency is low. Fast real time processes will not work, but most applications with more moderate timing demands are ideally suited for this system.

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    Generellt mät- och styrsystem
  • 41.
    Thelander Lööf, Hans
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Att styra en konferensenhet med gester2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The project is conducted in cooperation with a company that manufactures conference units. Conference units usually consist of a user interface aimed at the person who sets up the meeting, limiting the other participants' ability to interact with the device. The purpose of the project is to facilitate other participants to interact with conference units, which can be done by means of gestures. The aim of the project is to produce a product for evaluation and testing. The product should be able to convert detected gestures to commands to control speaker volume and microphone. After a comparison of different methods and techniques, a phase-based gesture detection was selected with an infrared proximity sensor. Two PCBs were made, one consisting of a microcontroller and one consisting of a proximity sensor with three infrared LEDs. A software was developed for gesture detection. Test was done with hand movements to the right, left, up and down with a distance of approx. 30 cm between hand and sensor. The result shows a gesture detection of four different gestures. In future developments, these can be converted into commands that can control speaker volume as well as microphone on conference device.

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    Att styra en konferensenhet med gester
  • 42.
    Tjällskog, David
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Optimering av ultraljudssändare- och mottagare avseende räckvidd, strålningsvinkel och energiförbrukning2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Embedded Systems Lab at Umeå University is currently part of a research project with the purpose to examine the behavior of dairy cows inside a barn. Each cow needs to be tracked with a precision of 50 cm, and since GPS-technique has poor functionality at indoor environments, an indoor positioning system needs to be developed.

    Embedded Systems Lab has already developed an indoor positioning system using IR-light and radio, but since this system demands extensive infrastructure and is rather expensive, an alternate positioning system using ultrasonic pulses and radio is being examined.

    In this report the range, beam angle and current consumption of ultrasonic transmitters- and receivers are investigated. Three different driver stages for the transmitter is tested, and two amplifier solutions for the receiver. The report also describes how the length of the transmitted ultrasonic pulse affects the received signal, accessibility of a “shadowed” signal, and the effect of different sound frequency.

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    Optimering av ultraljudssändare
  • 43.
    Vidmark, Stefan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Röstigenkänning med Movidius Neural Compute Stick2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Omicron Ceti AB company had an Intel Movidius Neural Compute Stick (NCS), which is a usb device that may be loaded with neural networks to process data. My assignment was to study how NCS is used and to make a guide with examples. Using TensorFlow and the TFLearn help library a test network was made for the purpose of trying the work pipeline, from network training to using the NCS. After that a network was trained to classify 14 different words. Many different configurations of the network were tried, until a good example was found that was expanded upon until an accuracy of 86% with the test data was reached. The accuracy when speaking into a microphone was a bit worse at 67%. To process data with the NCS took a longer time than with TFLearn but used a lot less CPU power. However it’s not even possible to use TensorFlow/TFLearn in smaller systems like a Raspberry Pi, so whether it’s worth using the NCS depends on the specific usage scenario.

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    Röstigenkänning med Movidius Neural Compute Stick
  • 44.
    Viklander, Johan
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Simulation of a TCU Node on a Virtual CAN Bus2016Independent thesis Advanced level (degree of Master (Two Years)), 300 HE creditsStudent thesis
    Abstract [en]

    Electrical Control Units (ECUs) communicating on Controller Area Networks (CAN buses) are widely used in vehicle electrical systems. Being able to simulate these circuits and buses in a computer environment is beneficial during the development phase when access to test benches is limited and expensive. Simulations can also give a very detailed view of the entire system which in an ordinary lab setup would be practically impossible.

    BAE Systems Örnsköldsvik SIL Lab department works in the simulation environment CANoe supplied by Vector Informatik GmbH. BAE Systems have a simulation model of their central communication circuit. Unlike the less complicated circuits on the bus it cannot be integrated in the CANoe simulation environment. The less complicated nodes are modelled to usable extent but this is not possible with the central communication circuit. This report presents a possible solution to facilitate communication between the simulated ECU and the CANoe simulation environment under certain real-time constraints.

    A solution was achieved with a combination of an external program which handled shared memory with callback functions and Vector's Fast Data eXchange protocol (FDX).

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  • 45. Vreča, Jure
    et al.
    Sturm, Karl J. X.
    Gungl, Ernest
    Merchant, Farhad
    Bientinesi, Paolo
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Leupers, Rainer
    Brezočnik, Zmago
    Accelerating Deep Learning Inference in Constrained Embedded Devices Using Hardware Loops and a Dot Product Unit2020In: IEEE Access, E-ISSN 2169-3536, Vol. 8, p. 165913-165926Article in journal (Refereed)
    Abstract [en]

    Deep learning algorithms have seen success in a wide variety of applications, such as machine translation, image and speech recognition, and self-driving cars. However, these algorithms have only recently gained a foothold in the embedded systems domain. Most embedded systems are based on cheap microcontrollers with limited memory capacity, and, thus, are typically seen as not capable of running deep learning algorithms. Nevertheless, we consider that advancements in compression of neural networks and neural network architecture, coupled with an optimized instruction set architecture, could make microcontroller-grade processors suitable for specific low-intensity deep learning applications. We propose a simple instruction set extension with two main components-hardware loops and dot product instructions. To evaluate the effectiveness of the extension, we developed optimized assembly functions for the fully connected and convolutional neural network layers. When using the extensions and the optimized assembly functions, we achieve an average clock cycle count decrease of 73% for a small scale convolutional neural network. On a per layer base, our optimizations decrease the clock cycle count for fully connected layers and convolutional layers by 72% and 78%, respectively. The average energy consumption per inference decreases by 73%. We have shown that adding just hardware loops and dot product instructions has a significant positive effect on processor efficiency in computing neural network functions.

  • 46.
    Wennström, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Kontinuerlig temperaturmätning i bädden på gratevagnar2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Luossavaara-Kiirunavaara Aktiebolag (LKAB) is a mining group with iron ore mining as the main business. One of the products is produced by refining iron ore to iron pellets, which is a quality and environmentally clever product  in steel production.

                                       

    When iron pellets are produced by roasting green pellets the temperature is very important. The goal is to get as much oxidation as possible from hematite to magnetite and to get correct mechanical properties. To control the process it’s important to know the temperature of the green pellets specifically and not the surrounding mechanical structure, ceramics lining in the furnace and the influence from radiation.

     

    The goal of the project is to examine possibilities to measure temperature with a permanent measurement system of green pellets which are transported on grate cars trough pellet plant. The measurement system has to meet some requirements of environment, portability and operating time.

    Analysis of the environment has been made to get specification of what a measurement system has to withstand. Proposition about assembly location has been investigated by analysis of the environment. A thermal analysis has been made of electronic components, especially electronic components that can be used in a measurement system. A analysis has also been made of which electronic components that are suited for a measurement system and can withstand the heat. A development measurement system has been developed from the results of the analysis. The system has been constructed to measure the temperature of what a system can be exposed of on a grate car. This with wireless and data-logging support and future measurements possibilities with three thermocouples of type S.

     

    Wireless data transfer was examined to see what type is most suited for the task with knowledge of environment, transmission range, radiation and power consumption. Power sources was examined to find a power source with longest working time and highest functionality. Heat insulation and reflective materials has been investigated with the goal to get the temperature in the system enclosure as low as possible. Some different types of temperature sensors that can measure temperatures up to 1500°C and which can be mounted on a grate car has been evaluated.

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    Kontinuerlig temperaturmätning i bädden på gratevagnar
  • 47.
    Yekeh, Farahnaz
    et al.
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Pordel, Mostafa
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Almeida, Luís
    University of Porto.
    Behnam, Moris
    Mälardalen University.
    Portugal, Paulo José
    University of Porto.
    Exploring alternatives to scale FTT-SE to large networks2011In: 6th IEEE International Symposium on Industrial Embedded Systems, 2011Conference paper (Refereed)
    Abstract [en]

    Nowadays, most complex embedded systems follow a distributed approach in which a network interconnects potentially large numbers of nodes. One technology that is being increasingly used is switched Ethernet, but real-time variants of this protocol typically limit scalability. In this paper, we focus on the scalability of the Flexible Time Triggered communication over Switched Ethernet (FTT-SE), which has been proposed to support hard real-time applications in a flexible and predictable manner. Moreover, time-triggered and event-triggered communication methods are supported in this protocol. FTT-SE has already been explored and investigated for small scale networked applications. In this paper we address the protocol scalability and suggest three different solutions with a qualitative assessment. © 2011 IEEE.

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