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Due to close coupling to hardware and lack of software engineering technologies, the control software in digitally controlled power conversion systems is difficult to design and maintain. This is a natural consequence of a topology- or application-driven design approach. This research work proposes a distributed, modular, open control architecture for power conversion systems to reduce control design complexity, encapsulate and localize design dependencies, reduce unnecessary redesign effort and improve software quality. Dataflow style is chosen as the architectural style for the proposed control architecture based on comparative analysis. The detailed implementation of the dataflow architecture is presented. The resulting dataflow control software is evaluated in comparison to the legacy approach to control design used in industry and academia. The dataflow control software for a 3-phase voltage source inverter is also tested on a real PEBB-based converter system. To further explore the flexibility of control composition that is brought by the dataflow approach, the feasibility of dynamic control reconfiguration is also presented as an important future research direction. / Ph. D.

With ever increasing contents (safety, driver assistance, infotainment, etc.) in today's automotive systems that rely on electronics and software, the supporting architecture is integrated by a complex set of heterogeneous data networks. A modern automobile contains up to 100 ECUs and several heterogeneous communication buses (such as CAN, FlexRay, etc.), exchanging thousands of signals. The automotive Original Equipment Manufacturers (OEMs) and suppliers face a number of challenges such as reliability, safety and cost to incorporate the growing functionalities in vehicles. Additionally, reliability, safety and cost are major concerns for the industry. One of the important challenges in automotive design is the efficient and reliable transmission of signals over communication networks such as CAN and CAN-FD. With the growing features in automotives, the OEMs already face the challenge of saturation of bus bandwidth hindering the reliability of communication and the inclusion of additional features. In this dissertation, we study the problem of optimization of bandwidth utilization (BU) over CAN-FD networks. Signals are transmitted over the CAN/CAN-FD bus in entities called frames. The signal-to-frame-packing has been studied in the literature and it is compared to the bin packing problem which is known to be NP-hard. By carefully optimizing signal-to-frame packing, the CAN-FD BU can be reduced. In Chapter 3, we propose a method for offset assignment to signals and show its importance in improving BU. One of our contributions for an industrial setting is a modest improvement in BU of about 2.3%. Even with this modest improvement, the architecture's lifetime could potentially be extended by several product cycles, which may translate to saving millions of dollars for the OEM. Therefore, the optimization of signal-to-frame packing in CAN-FD is the major focus of this dissertation. Another challenge addressed in this dissertation is the reliable mapping of a task model onto a given architecture, such that the end-to-end latency requirements are satisfied. This avoids costly redesign and redevelopment due to system design errors. / Ph. D.

Energy consumption is increasingly affecting battery life and cooling for real- time systems. Dynamic Voltage and frequency Scaling (DVS) has been shown to substantially reduce the energy consumption of uniprocessor real-time systems. It is worthwhile to extend the efficient DVS scheduling algorithms to distributed system with dependent tasks. The dissertation describes how to extend several effective uniprocessor DVS schedul- ing algorithms to distributed system with dependent task set. Task assignment and deadline assignment heuristics are proposed and compared with existing heuristics concerning energy-conserving performance. An admission test and a deadline com- putation algorithm are presented in the dissertation for dynamic task set to accept the arriving task in a DVS scheduled real-time system. Simulations show that an effective distributed DVS scheduling is capable of saving as much as 89% of energy that would be consumed without using DVS scheduling. It is also shown that task assignment and deadline assignment affect the energy- conserving performance of DVS scheduling algorithms. For some aggressive DVS scheduling algorithms, however, the effect of task assignment is negligible. The ad- mission test accept over 80% of tasks that can be accepted by a non-DVS scheduler to a DVS scheduled real-time system.

SOFA-HI is an extension of the SOFA 2 component system,which is developed at Department of distributed and dependable systems. SOFA-HI focuses on support for development of real-time embedded applications using component-based approach. This thesis extends existing SOFA-HI implementation with support for development and deployment of SOFA-HI application to nxtOSEK platform which is a small-footprint real-time operating system and board support package for LEGO Mindstorms NXT. In particular, existing tools for application development and deployment are extended to support nxtOSEK platform. The thesis further provides pre-made components to allow communication with standard NXT sensors and actuators. Powered by TCPDF (www.tcpdf.org)

Embedded in circuit emulator (EICE) is the most common and widely used debugging techniques for microprocessors. Because the ICE is capable to provide diverse debugging and testing mechanisms, such as: single-step debugging, breakpoints setting and detection, monitoring, and modification of internal resources. However, the shortcoming of the conventional embedded in circuit emulator (EICE) is that the operation of the processor has to be suspended during debugging, which is categorized as static debugging (Static Debug) and is infeasible for real-time debugging. Therefore, this paper proposes a design alternative to support the real-time system debugging without suspending the microprocessor via the debug hardware Coprocessor14 (the Debug Coprocessor). In this paper, the embedded in circuit emulator is combined with Coprocessor 14 to provide both the static debugging and Run-time system debugging. After incorporating CP14 with the debugging mechanism, the control of the debug hardware is no longer limited to use the IEEE 1149.1 test port during debugging. On the other hand, the set of debugging constraints and the observation of the internal state of the microprocessor can be achieved by inserting the Coprocessor instruction at the program level.

Networked Control Systems (NCS) are distributed control systems where the sensor signals to the controllers and the control data to the actuators are enclosed in messages and sent over a communication network. On the one hand, the design of an NCS requires ensuring the stability of the control system and achieving system response that is as close as possible to that of an ideal system which demands network resources. On the other hand, these resources are limited and have to be allocated efficiently to accommodate for future system extensions as well as applications other than control purpose. Furthermore the NCS design parameters for the control system messages and the message transmission over the network are interdependent. In this thesis, we propose &ldquo / Integrated NCS Design (INtERCEDE: Integrated NEtwoRked Control systEm DEsign)&rdquo / a novel algorithmic approach for the design of NCS which ensures the stability of the control system, brings system response to that of an ideal system v as close as desired and conserves network bandwidth at the same time. The core of INtERCEDE is a bargaining game approach which iteratively calculates the message parameters and network service parameters. Our experimental results demonstrate the operation of INtERCEDE and how it computes the optimal design parameters for the example NCS.

This document is a master’s thesis analyzing an automated fuel pump management system. In the first chapters we take a general overview of the system and the main problems that we will be facing during the planning and design phases of the project. Later we propose and analyze possible solutions for these problems. Technical system information is revealed in the later chapters. Functional and non functional requirements are discussed along with the main UML diagrams. The research phase of the thesis provides detailed system analysis and software quality reports which later are used to create proposed changes to the system. These changes are analyzed, designed and coded in the final - experimental part of the thesis. The main proposal is to convert the system architecture from flow driven to event driven. This change helps to solve several uncovered architectural problems as well as improve the general quality of the system. These changes are tested and analyzed in the experimental chapter of the thesis and finally the conclusions are made. The main conclusion is that the proposed architectural changes were chosen correctly. This is also supported by the experimental data.

Roboto kūrimas yra nepaprastai brangus procesas. Sukonstruoti prototipą sunaudojama daug lėšų, o paaiškėjus trūkumams gali tekti jį perdaryti ne vieną kartą. Nemažiau sudėtingas yra algoritmų kūrimas roboto valdymui. Išbandyti valdančią programą su realiu prototipu sudėtinga, nes klaidos gali sukelti tiek smulkių gedimų tiek stipriai apgadinti įrangą. Šiame dokumente yra gilinamasi į roboto elgesio simuliavimą virtualioje erdvėje. Nagrinėjamos roboto simuliavimo aplinkos, teikiančios galimybę suprogramuoti ir išbandyti robotą valdančius algoritmus. Kreipiamas didelis dėmesys į tokios sistemos naudojimo paprastumą ir galimybę ją naudoti moksleivių skatinimui domėtis programavimu. Autorius pateikia projektą naujos simuliavimo aplinkos kūrimui ir realizuoja šią sistemą. Atliekamas tyrimas siekiant nustatyti kaip yra kuriamos roboto valdančios programos. Yra palyginama naujai sukurtos sistemos galimybė realizuoti valdymo algoritmus su rinkoje esančiu komerciniu sprendimu – Webots. Yra pateikiamos dvi roboto konstrukcijos su apibrėžtu roboto elgesiu ir suprogramuojamas valdymo kodas abejose sistemose. Roboto elgesio reikalavimuose atliekamas pakeitimas ir tiriama kokią įtaką tai turi robotą valdančios programos kodui. Galiausiai yra pristatoma naujai sukurta roboto simuliavimo aplinka. Aprašomas sistemos vartotojo vadovas, paaiškinama grafinė vartotojo sąsaja. / The process of robot creation is extremely expensive. It requires a lot of expenses to build a prototype and mistakes in design can lead to several rebuilds. No less expensive is a challenge of designing control program for the robot, as testing it with a prototype can cause harm to the construction or even destroy it. This document focuses on the simulation of robot behavior in virtual environment. Egzisting simulation environmets, that allow programming and simulating of control scripts, are being explored here. A lot of attention is paid to simplicity of the software interface and possible usage for children to learn and enjoy programming. The author makes a proposal for new simulation environment and implements the software. The research is made on the implementation of control programs for robots. The way how the control program is implemented is compared to an egzisting comercial simulation environment – Webots. The two specifications for robot design and behavior is provided and the solutions for control programs are designed and compared. The modification in robot specifications are brought up and those solutions are modified to comply with the change. Finally the designed software is presented and explained. The chapter contains user guide, a specification for graphical user interface and an explanation of it‘s usage.

Real-time systems are systems which must produce a result within a given time frame. A result given outside of this time frame is as useless as not delivering any result at all. It is therefore essential to verify that real-time systems fulfill their timing requirements. A model of the system can facilitate the verification process. This thesis investigates two possible methods for modeling a real-time system with respect to CPU-utilization and latency of the different components in the system. The two methods are evaluated and one method is chosen for implementation.The studied system is the decoder of a WCDMA system which utilizes a real-time operating called system OSEck. The methodology of analyzing the system and different ways of obtaining measurements to base the model upon will be described. The model was implemented using the simulation library VirtualTime, which contains a model of the previously mentioned operating system. Much work was spent acquiring input for the model, since the quality of the model depends largely on the quality of the analysis work. The model created contains two of the studied systems main components.This thesis identifies thorough system knowledge and efficient profiling methods as the key success factors when creating models of real-time systems.