The Orbital Systems Company faces the really important issues such a lack of water, sewerage and even public health infrastructure. Its proposition of the Shower of the Future, which is a high-tech purification system that recycles water was inspired by the NASA, spaceship technology with limited sources of water and can be the solution of these problems. Due to the patented technology, which bases on the special filters, it is possible to reuse water. This idea, which is used in the shower, allows on more than 90% savings in water usage and 80% savings in energy, while producing water that is cleaner than average tap water. The company aims to provide this special technology not only to the hotels or hospitals, but also to the regular house to maintain the sustainability issue and even achieve the economic profit. The Shower of the Future is a new technology still in the developing phase. To achieve the goals of the company, in the software part of the system, two important problems have to be solved. First of them is the management issue. At this moment, three different versions of the showers, which differ in hardware and in software are in used. Much more versions adjusted to the place of destination such as hotel or hospital are planned. To manage the codes and integrate all of the possible version of the shower, the company desires to create one compatible software to control all of them. The mechanisms to integrate the codes by managing the configurable parameters of the system and to auto detect the version of the shower are proposed in the work. The second company’s issue is the improvement of the control system. As performed research and tests show, the temperature control in the Shower of the Future is too slow and inaccurate. To solve this problem, the identification process of the model was conducted and the PID controllers for the heater were designed. Due to specific structure of the shower, which introduce delays and disturbances, a single PID controller is not sufficient to maintain the control system. As a final controller, the switching PID controller created from previously designed PID controllers is proposed. Thanks to it, the temperature rising time is reduced 2 times, the overshoot, which was equal to 5 °C does not appear and the steady state error is diminished. Thanks to improvement of the temperature control system, much less water is wasted and much more energy is saved. The Shower of the Future of the Orbital System, which nevertheless needs improvements and more work, is only the first step in creating a new paradigm for daily water usage. The company and its product seriously consider the sustainability and environment aspect.

Modern embedded systems development poses new challenges to a designer due to the global reachability of the contemporary market. One product shipped to different countries or customers should satisfy varying conditions, standards and constraints. Variability of a developed system should be taken into account by a designer. In a case of the embedded heterogeneous systems, this problem becomes challenging. Along with the variability heterogeneity of a system introduces new tasks, which should be addressed during design process. In this work, we propose a technology independent design flow. The proposed solution is supported by state-of-the-art tools and takes into account variability, partitioning, interfacing and dependency resolving processes. This thesis is conducted as a case study. We explored a design process of an industrial project, identified existing challenges and drawbacks in the existing solutions. We propose a new approach to a design flow of heterogeneous embedded systems. Also, a tool, supporting the presented solution, is implemented, which would allow a developer to include this approach into everyday design flow in order to increase a development speed and enable a task automation.

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Today’s embedded systems require more and more performance but they are still required to meet power constraints. Single processor systems can deliver high performance but this leads to high power consumption. One solution to this problem is to use a multiprocessor system instead which is able to provide high performance and at the same time meet the power constraints. The reason that such a system can meet the power constraints is that it can have a lower clock frequency than a similar single processor system. The focus of the project is to explore possibilities when developing new multiprocessor systems. The project makes a comparison of asymmetric multiprocessing (AMP) systems and symmetric multiprocessing (SMP) systems in terms of task management and communication between the processors. A comparison is made between the Advanced High-performance Bus (AHB) interface and the Advanced eXtensible Interface (AXI). The fixed priority and round-robin arbitration algorithms is also compared. The project also contains a practical part where a demo is developed to show that an inter-processor communication using exclusive access is possible to implement. The theoretical part of the project containing the comparisons result in good comparisons that can be used to get an overview of what to use when developing new Multiprocessor System on Chip (MPSoC) designs. The demo developed in this project failed to meet the requirement of having a fully functional spinlock. This problem can be solved in the future if new hardware is developed. / Dagens inbyggda system kräver mer och mer prestanda men de måste fortfarande klara av kraven kring strömförbrukning. System med en processor kan leverera hög prestanda men detta leder till hög strömförbrukning. En lösning till detta problem är att använda ett multiprocessorsystem istället som klarar av att leverera hög prestanda och samtidigt klara av kraven kring strömförbrukning. Anledningen till att denna typ av system klarar av kraven kring strömförbrukning är att de kan använda en lägre klockfrekvens än ett system med en processor. Fokuset på detta projektet ligger på att utforska möjligheterna som finns när nya multiprocessorsystem ska utvecklas. Projektet gör en jämförelse mellan asymmetriska och symmetriska multiprocessorsystem i termer av uppgiftshantering och kommunikation mellan processorerna. En jämförelse har gjorts mellan Advanced High-Performance Bus (AHB) gränssnittet och Advanced eXtensible Interface (AXI) gränssnittet. Fixed priority och round-robin algoritmerna för hantering av krockar mellan processorerna har också jämförts. Det finns även en praktisk del i projektet där en demo har utvecklats för att visa en fungerande kommunikation mellan processorer som använder funktionaliteten för exklusiv åtkomst till den gemensamma bussen. Den teoretiska delen av projektet som innehåller jämförelserna resulterar i bra jämförelser som kan användas när nya multiprocessorsystem utvecklas. Demon som har utvecklats i detta projekt misslyckades med att klara av kravet kring att ha ett fullt fungerande lås. Detta problemet kan lösas i framtiden ifall ny hårdvara utvecklas.

During the last decades, improved sensor and hardware technologies as well as new methods and algorithms have made self-driving vehicles a realistic possibility in the near future. Thanks to this technology enhancement, many leading automotive and technology companies have turned their attention towards developing advanced driver assistance systems (ADAS) and self-driving vehicles. Autonomous vehicles are expected to have their first big impact in closed areas, such as mines, harbors and loading/offloading sites. In such areas, the legal requirements are less restrictive and the surrounding environment is more controlled and predictable compared to urban areas. Expected positive outcomes include increased productivity and safety, reduced emissions and the possibility to relieve the human from performing complex or dangerous tasks. Within these sites, different truck and trailer systems are used to transport materials. These systems are composed of several interconnected modules, and are thus large and highly unstable while reversing. This thesis addresses the problem of designing efficient motion planning and feedback control frameworks for such systems. First, a cascade controller for a reversing truck with a dolly-steered trailer is presented. The unstable modes of the system is stabilized around circular equilibrium configurations using a gain-scheduled linear quadratic (LQ) controller together with a higher-level pure pursuit controller to enable path following of piecewise linear reference paths. The cascade controller is then used within a rapidly-exploring random tree (RRT) framework and the complete motion planning and control framework is demonstrated on a small-scale test vehicle. Second, a path following controller for a reversing truck with a dolly-steered trailer is proposed for the case when the obtained motion plan is kinematically feasible. The control errors of the system are modeled in terms of their deviation from the nominal path and a stabilizing LQ controller with feedforward action is designed based on the linearization of the control error model. Stability of the closed-loop system is proven by combining global optimization, theory from linear differential inclusions and linear matrix inequality techniques. Third, a systematic framework is presented for analyzing stability of the closed-loop system consisting of a controlled vehicle and a feedback controller, executing a motion plan computed by a lattice planner. When this motion planner is considered, it is shown that the closed-loop system can be modeled as a nonlinear hybrid system. Based on this, a novel method is presented for analyzing the behavior of the tracking error, how to design the feedback controller and how to potentially impose constraints on the motion planner in order to guarantee that the tracking error is bounded and decays towards zero. Fourth, a complete motion planning and control solution for a truck with a dolly-steered trailer is presented. A lattice-based motion planner is proposed, where a novel parametrization of the vehicle’s state-space is proposed to improve online planning time. A time-symmetry result is established that enhance the numerical stability of the numerical optimal control solver used for generating the motion primitives. Moreover, a nonlinear observer for state estimation is developed which only utilizes information from sensors that are mounted on the truck, making the system independent of additional trailer sensors. The proposed framework is implemented on a full-scale truck with a dolly-steered trailer and results from a series of field experiments are presented.

Arbete på kandidatnivå som behandlar 3D skanning vid olika vinklar och de resultat de ger vid olika avstånd.

This thesis uses one of Brain Computer Interface (BCI) products, NeuroSky headset, to design a prototype model to control window blind by using headset’s single channel electrode. Seven volunteers performed eight different exercises while the signal from the headset was recorded. The dataset was analyzed, and exercises with strongest power spectral density (PSD) were chosen to continue to work with. Matlabs spectrogram function was used to divide the signal in time segments, which were 0.25 seconds. One segment from each of these eight exercises was taken to form different combinations which were later classified.The classification result, while using two of proposed exercises (tasks) was successful with 97.0% accuracy computed by Nearest Neighbor classifier. Still, we continued to investigate if we could use three or four thoughts to create three or four commands. The result presented lower classification accuracy when using either 3 or 4 command thoughts with performance accuracy of 92% and 76% respectively.Thus, two or three exercises can be used for constructing two or three different commands.

Sensors with very low power consumption are required so that they can last a long time without the need to replace the batteries very often. Low power sensors can save significant cost and time incurred in battery replacement, especially in establishments and organizations that span over several buildings, floors and rooms. In this thesis, we investigate the use of the low-power wireless protocol Z-wave for sensors solutions that can last for approximately 10 years. An algorithm was created and we concluded that 10 years on a 480 mAh battery is not possible and the expected years need to be lowered or we need to increase the battery capacity.

The demand for computing power and performance in real-time embedded systems is continuously increasing since new customer requirements and more advanced features are appearing every day. To support these functionalities and handle them in a more efficient way, multi-core computing platforms are introduced. These platforms allow for parallel execution of tasks on multiple cores, which in addition to its benefits to the system's performance introduces a major problem regarding the timing predictability of the system. That problem is reflected in unpredictable inter-core interferences, which occur due to shared resources among the cores, such as the system bus. This thesis investigates the application of different optimization techniques for the offline scheduling of tasks on the individual cores, together with a global scheduling policy for the access to the shared bus. The main effort of this thesis focuses on optimizing the inter-core data propagation delays which can provide a new way of creating optimized schedules. For that purpose, Constraint Programming optimization techniques are employed and a Phased Execution Model of the tasks is assumed. Also, in order to enforce end-to-end timing constraints that are imposed on the system, job-level dependencies are generated prior and subsequently applied during the scheduling procedure. Finally, an experiment with a large number of test cases is conducted to evaluate the performance of the implemented scheduling approach. The obtained results show that the method is applicable for a wide spectrum of abstract systems with variable requirements, but also open for further improvement in several aspects.

The aim of this thesis is to create a port of the Zephyr realtime operating systemfor the LEON processor platform. The LEON is a frequently used computing corefor spaceflight applications, with ample flight heritage. It is based upon the wellestablished SPARC v8 instruction set, and offers many extensions to ease softwaredevelopment and increase overall processor performance. An overview of the nec-essary steps towards a functional architecture port is given in this report. Specialemphasis is put upon the interrupt handling and context switching. One LEONspecific feature introduced with the GR716 LEON3-FT microcontroller, registerwindow partitioning, is used to increase the performance of the context switchingmechanism in the operating system. By using this feature, context switching timehas shown to decrease significantly, while easing verification of the overall softwaresystem by providing dedicated partitions for tasks with hard realtime requirements. / Det övergripande målet med examensarbetet är att porta Zephyr realtidsopera-tivsystem (OS) till LEON processorplattformen. LEON processorn är ursprungligendesignad för och förekommer ofta i datorsystem inom rymd p.g.a. sina feltolerantaegenskaper. LEON är kompatibel med den öppna SPARC v8 instruktionsuppsät-tningen vilken också tillåter utökning och anpassningar. Rapporten ger läsaren enöverblick av vilka steg som är nödvändiga för att skapa en fungerande arkitektur-port av ett OS. Vidare beskriver rapporten mer i detalj designen kring trådväxlingoch avbrottshantering, samt hur dessa anpassas för att utnyttja LEON specifikautökningar av SPARC till att nå högre prestanda. GR716 LEON3-FT introducerarpartitionering av SPARC registerfönster för att kunna minska tiden det tar opera-tivsystemet att växla trådar. Denna funktion har inte använts tidigare i något OS,och är därför av särskilt intresse att studera och karakterisera. Resultaten visar atttrådväxlingstiden minskat signifikant, samtidigt som determinismen blivit bättreoch därigenom är det nu enklare att designa system med hårda realtidskrav.