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Modern embedded systems---autonomous vehicle-to-vehicle communication, smart cities, and military Joint All-Domain Operations---feature increasingly heterogeneous distributed components. As a result, existing communication methods, tightly coupled with specific networking layers and individual applications, can no longer balance the flexibility of modern data distribution with the traditional constraints of embedded systems. To address this problem, the investigation herein presents a domain-specific language, designed around the Representational State Transfer (REST) architecture, most famously used on the web. Our language, called the Communication Language for Embedded Systems (CLES), supports both traditional point-to-point data communication and management and allocation of decentralized distributed processing tasks. To meet the traditional constraints of embedded execution, CLES' novel runtime allocates processing tasks across a heterogeneous network of embedded devices, overcoming limitations from other modern distribution methods: centralized task management and limited operating system integration. CLES was evaluated with performance micro-benchmarks, implementation of distributed stochastic gradient descent, and application to the design of versatile stateless services for vehicle-to-vehicle communication and military Joint All-Domain Command and Control (JDAC). From this evaluation, it was determined that CLES meets the data distribution needs of realistic cyber-physical embedded systems. / Master of Science / As computers become smaller, cheaper, more powerful, and energy efficient, they are increasingly used in cyber-physical systems such as planes, trains, and automobiles, as well as large-scale networks such as power plants and smart cities. The field of embedded computing is facing new challenges involving the communication and coordination of large numbers of different devices. Some of the software challenges within embedded device communications are: flexibility both in ability to run on different devices and use different communication links such as cellular, Wi-Fi, or Bluetooth, performance constraints of low-power embedded devices, latency and reliability to ensure safe operations, and the schedule and cost of development. To address these challenges, this thesis presents a new programming language, designed around the Representational State Transfer (REST) architecture, most famously used in HTTP to drive the web. Our language, called the Communication Language for Embedded Systems (CLES), supports both traditional point-to-point data communication designed to prioritize latency and reliability, as well as a standalone application or runtime that can be run on an embedded device to accept requests for processing tasks. CLES and its supporting Software Development Kit (SDK) is designed to allow for quick and cost effective development of flexible low-latency device to device communications and large scale distributed processing on embedded devices.

Gas Chromatography (GC) is one of the most important and widely used tools in analytical chemistry. However, they are bulky, have a longer measurement cycle, and consume a high amount of power. Micro-Gas Chromatography (µGC) is portable and energy-efficient, which allows onsite, real-time biological, forensic, and environmental analyses. This thesis presents a ready-to-deploy implementation of microfabricated gas chromatography (µGC) system capable of separating complex samples. We describe robust, modular, and scalable hardware and software architecture based on Real-Time Operating System (RTOS) and Python Graphical User Interface (GUI) integrated with various microfabricated devices to realize a fully functional µGC system. A sample heater for headspace injection, microfabricated separation column (µSC), a Photoionization Detector (PI-D), and a flow controller unit are integrated with the modular hardware and software to realize a fully functional Vacuum Outlet µGC system. We have designed a novel auto-calibration method for temperature calibration of the microfabricated devices which does not require changing the electronic circuitry or reprogramming the device. The vacuum outlet µGC setup is tested with various mixture of analytes. For these experiments, an average relative standard deviation (RSD) for retention time repeatability of 2.5% is achieved. Data processing techniques for raw chromatograms, including baseline correction and peak detection, are implemented on a microcontroller board and tested extensively as a part of this work. A novel algorithm for multidimensional analysis for the identification of co-eluting compounds in complex samples is implemented with a prediction accuracy of 94%. / Master of Science / Toxic volatile organic compounds (VOCs) such as benzene and toluene found in gasoline and xylene used in ink, rubber, and leather industries are of concern as they are present at elevated concentrations due to their higher vapor pressure. Sufficient exposure to these toxicants, even at lower concentrations like 100 parts-per-billion-volume (ppbv), may cause adverse health effects. Gas Chromatography (GC) has been the established method for assessing the presence and concentration of VOCs in the environment. Traditional GC systems are bulky, power-hungry, expensive, and require expert supervision for analysis. Recent research in microelectromechanical systems (MEMS) has reduced the size of the GC components, also called micro-GC (µGC), while improving the performance. The majority of the research and development of µGC is aimed at advancing microfabricated components such as preconcentrators, separation columns, and gas detectors. However, the integration of these different components is an important topic that requires more investigation. In this thesis, we present a robust and scalable software and hardware architecture that can be used to develop a portable and modular µGC system. The thesis discusses different experiments to calibrate various microfabricated devices, which are then used to build a fully modular µGC system. We show the separation capacity of the modular µGC system by passing complex compounds like kerosene and diesel. As the chromatogram from the µGC system has noise, the second part of the thesis explores data analysis techniques such as baseline correction, peak detection. These data analysis tools are used to filter the noise, detect relevant peaks in the chromatograms, and identify the compounds in a complex sample.

A ready-to-deploy implementation of microfabricated gas chromatography (microGC) system characterized for detecting hazardous air pollutants (HAPs) at parts-per-billion (ppb) concentrations in complex mixtures has been described. A microfabricated preconcentrator (microPC), a MEMS separation column with on-chip thermal conductivity detector (microSC-TCD), the flow controller unit, and all the necessary flow and thermal management as well as user interface circuitry are integrated to realize the fully functional microGC system. The work reports extensive characterization of microPC, microSC and micro]TCD for target analytes: benzene, toluene, tetrachloroethylene, chlorobenzene, ethylbenzene, and p-xylene. Limit of Detection (LOD) of ~1 ng was achieved, which corresponds to 10 min sampling time at a flow rate of 1 mL/min for analyte present at ~25 ppbv concentration. An innovative method for generating very sharp injection plugs from the microPC even in the presence of flow sensitive detectors like micro]TCD is described. A one-to-one comparison between microGC system and conventional Automated Thermal Desorption-Gas Chromatograph-Flame Ionization Detector (ATD GC-FID) system for real gasoline samples in simulated car refueling scenario is reported. / Master of Science

This thesis presents the design and implementation of a transparent messaging protocol for distributed communication between processors. The processors are designed using dataflow architecture. The protocol ensures transparent asynchronous communication between distributed processes. The protocol is designed such that an application can run without change in virtually any kind of distributed configuration, where configuration is the number of controllers used in the system plus the processor allocation strategy used. It also enables an automated processor allocation strategy to transparently configure an application for any number of processor nodes without requiring any changes or recompilation. The protocol works well even for single-controller applications and for a pre-defined allocation of processors to controllers. The thesis further includes an analysis of the time required for one complete cycle of inter-processor communication. / Master of Science

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.

Automotive embedded systems used much in the main body control system. Also because the system needs to meet functional requirement, environment requirement, timing requirement, interface requirement and Failure Mode and Effects Analysis (FMEA) so it is necessary to have an automotive embedded systems modeling methodology. Therefore, this study proposes an automotive embedded systems modeling methodology which combines MDA and UML, and detailed description of the model diagram used by each modeling phase and the diagram modeling method and steps. System development team can be clearly implemented in accordance with the methods and steps for automotive embedded system modeling. The methodology also can be used as the communication standard of the system development team. Systems modeling during system modular can promote module reuse rate in order to enhance the efficiency of system development. The methodology of this study is based on design science research methods, usability evaluation of the modeling methodology is implemented for the modeling of demand for Parking aid control unit, the PIM modeling and code conversion. With prove the availability of this modeling methodology. From the results of the assessment system development team can be based on the methodology of modeling methods and procedures to express the results in line with the needs and systems analysis and design of automotive embedded systems and convert the system operating platform and code.

Generating code from software models is considered to be a new generation leap within software development methods. The objective of this M.Sc. project is to evaluate how different approaches to modelling and code generation affect embedded systems software development and propose recommendations on how to improve software development. Two product areas at Saab Surveillance EW Systems in Järfälla, Stockholm, are used as study objects. A research overview is made to highlight themes regarding modelling, code generation and software development in general. Based on these, interviews are held with system engineers and software developers at each product area, where they use different modelling and code generation approaches. The two development processes are described thoroughly. Challenges and advantages related to each area’s approach are investigated. Software development within product area A is affected by the product complexity and the larger scale of the development, including projects running over a longer time with more teams involved. Recommendations include enabling code generation by aligning it with other investments on process improvement and limiting the approach to generating some system components. Software developers within product area B can use full code generation, enabled by the limited product complexity. The product area is affected by software standards and external requirements on the process. Recommendations include extending the modelling approach to make it easier to trace functionality from system to software level. Conclusions are that both product areas can apply modelling and code generation to more software development activities to improve their respective development processes.

In this work I have evaluated a method to model, measure and analyze the power consumption of embedded systems. The method combines current measurement with debug trace data telling which parts of the systems that are enabled. This makes it possible to compute the individual current consumption of the parts in the system from a single measurement point. The method allows an embedded systems engineer to determine the power consumption of individual parts in a system to either get an overview or to compare several revisions of hardware and/or software with each other. The method also captures the system dynamics of the power delivery route. This makes the model consumption behave more like the actual system around state transitions. The case study is focused on the Arm-based microcontroller CC2650 from Texas Instruments and uses the I-scope/I-jet probe from IAR Systems to measure current consumption and collect trace data.