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This paper aims to bring a different view and approach to embedded device design. The main focus of this article is to enumerate the key components of a resilient design, define them and try to apply them to a real-life scenario. This can show possible approaches and rules which can make the overall design of a device or a systen more resilient to various adverse conditions and situations.

Using modern methods to control vehicle access is becoming more common. At present, various approaches and ideas are emerging on how to ensure the access in use cases reflecting car rental services, car sharing, and fleet management, where the process of assigning car access to individual users is dynamic and yet must be secure. In this paper, we show that this challenge can be resolved by a combination of the PKI technology and an access management system. We implemented a vehicle key validation process into an embedded platform (ESP32) and measured the real-time parameters of this process to evaluate the user experience. Utilizing the SHA256-RSA cipher suite with the key length of 3072 bits, we measured the validation time of 46.6 ms. The results indicate that the user experience is not worsened by the entry delays arising from the limited computing power of embedded platforms, even when using key lengths that meet the 2020 NIST recommendations for systems to be deployed until 2030 and beyond.

This paper attempts to describe redundancy as an important source of resilient properties within the Safety-II concept. The document first describes the resilience itself and mentions both the genesis of the term and several definitions across disciplines. Last but not least, it provides an appropriate definition of general resilience. The first part also describes the basic attributes of resilience and the principles, that can be used to secure these attributes. The next section describes the fault hypothesis. This section discusses the act possibility of system faults and their consideration in safety design. This section also describes the 3-dimensional failure model, which allows simplification of fault analysis. The following sections describe Safety-I and Safety-II concepts. The context of these two concepts is described here. Chapter 6 describes the use options of resilient properties within the Safety-II concept. The last chapter tries to describe the possibilities of classification of resilience using redundancy. Firstly, the importance of redundancy for resilience and then the use of a 3-dimensional model for redundancy classification are explained.

The paper presents a SkuBATCh system for batch process control designed and implemented based on ISA-88 and ISA-95 standards. The multitier system is based on the .NET framework, using modern OPC UA protocol for communication. The system is used in the teaching laboratory and serves to teach students and to demonstrate the principles described in the standards. The paper describes both the way of implementation and potential use. It is a combination of modern technologies namely OPC UA and control by superior batch system. You can find the mapping of the procedural model to the PLC and the data flow. SkuBATCH is then tested on a virtual production model. This whole solution is then taught as an example of batch production.

This paper discusses automatic code generation utilizing the Matlab/Simulink environment for safety-critical systems. According to IEC 61508 and other relevant standards, the developed product has to comply with appropriate requirements, and the same rule applies to the development process. The underlying environment comprises multiple user tools; in this article, therefore, the sophisticated use of well-combined tools is characterized into a tool-chain assembly supporting the automatic model-based deployment within the ARM Cortex-R architecture. The code generation process is suitably illustrated via an exemplary application. The presented workflow then generates reports, and these are briefly discussed in the given context. Using the real development kit, a PIL simulation is assembled and performed. Based on the results, compliance with the functional safety standard is addressed. This tool-chain assembly, set up within the employed environment, provides an alternative view on the standard V-model and enables the model-driven architecture concept to be incorporated into the commercial area.

This paper discusses usability of an adaptive human control model in the context of a simple Human-in-the-loop Cyber Physical Systems (HiLCPS). The first part of the paper characterizes human factor assessment with an emphasis on the modeling of human behavior. This section is followed by a description of the human control model structure, including a definition of the individual components and their roles during the control phases. Exploiting relevant theoretical background, the authors present an example of a human controller comprising the feedback component and two different implementations of a pursuit controller. The parameters of the controllers are obtained from data measured on a flight simulator controlled by a pilot during the defined task. The first results presented in this paper indicate the possibility of use the described human control structure in HiLCPS modeling and its potential for other, more complex experiments within human factor assessment.

This paper attempts to summarize information related to ensuring system resilience across disciplines. The first part outlines the reasons why the security in current systems is inadequate, generating the need to deepen the knowledge of the second generation of safety (Safety II). The authors also compare the views on safety from the perspectives of the current methods and resilience. Further, the paper also discusses the basic features required for a resilient system and presents the ideal definition of such a system. The final analysis then characterizes the methods to be applied in ensuring the resilience of industrial systems; importantly, this section also provides an example of how the current security scenarios can fail in high complexity systems. In this context, the demands on an industrial resilient control system are outlined, together with how the second generation safety approaches differ from the previously applied concept.

The goal of this paper is to present the possibilities of energy harvesting using the modern components called energy management systems. These circuits are integral parts of modern energy harvesting systems and are responsible for management of power supply, energy storage and flow of energy between individual components. This paper focuses on the E-PEAS AEM10940 circuit. It is a small device usable for low power embedded systems. Thus, its basic characteristic and properties obtained by repeated short-term and long-term measurements are presented and evaluated.

This paper presents the introduction to the Human-in-the-loop issue connected to the concept of the Cyber-physical systems (CPS). In this context, the brief overview of CPS is provided, with emphasis on the role of human in cooperation with CPS. Such systems are often called Human-in-the-Loop Cyber-Physical Systems (HiLCPSs). The following part of this paper brings the short background of HiLCPS and approaches for human performance assessment. The last part deals with example of human performance assessment based on the real data. For these purposes, several approaches is used, e.g. evaluation of measured human responses or evaluation of human dynamic properties based on the modelling of human behavior. The input data was collected using measurements with real human/pilots. Due to many realized tests with pilots in the different stage of training, there is statistically relatively significant set of input data.

In AC installations the Arc Fault Detection Devices are well established. However emerging high power (high current) DC application fields represent several challenges wit respect to arc faults and their detection. This paper presents arc fault signals in time domain and in frequency domain, discusses challenges associated with arc fault detection in the DC application domain and application of the UL1699B standard testing procedure for arc fault detection development in high current applications.

This paper describes an approach and implementation issues of client-side data encryption for thin client-web browser. Since the service provider may be a competitor of the service user, sensitive parts of data are encrypted and decrypted by the client. Cipher key generation and distribution issues are discussed: although the cipher key is kept in private, the paper shows the way for the key validation by the server side to maintain data consistency.

The goal of this article is to present and discuss the main parts in designing a CNC embedded motion controller. Firstly, usable motor and drivers are discussed. Then usable control components are presented. About the software, the velocity motion profiles are presented and discussed. Regarding the multi-axis control, some interpolation methods are presented and compared. The practical architecture of the motion controller is discussed and some approaches are compared. In the last part, some fault-tolerant techniques suitable for the controller are discussed. A new approach of fault tolerant method is presented and discussed.

The goal of this paper is to clarify the differences between ontologies and databases. The article describes, in a step-by-step manner, the parts in which differences occur. However, there are also similarities proving that ontologies and databases are not completely different. Based on these aspects, this paper presents various approaches to transforming a database to ontology. The conclusion summarizes and highlights the most important similarities and differences.

Introduction of real-time pricing models for the price of electricity may lead to a reduction in both economic and environmental burden compared with existing models. Thanks to the timely response to price changes during the day the user can achieve a reduction in the payments for energy. However, recent studies show that lack of knowledge of users and their unwillingness to adapt their habits to changing energy prices is the biggest obstacle to successful implementation of the model. In our work, we propose to solve this problem by introducing automatic optimal energy consumption scheduling framework. This article presents the authors extension in the past created MILP model for the optimization of household appliances. The model is extended by rules of behavior that allows preserving logical links in the course of periodically triggered optimization (so called receding horizon). We also present and test the software simulator, in which the designed model is implemented. The application simulates the operation of Building Energy Manager, which based on user preferences, prediction electricity prices and other important parameters controls the operation of appliances in the house.

The work aims at a development of positioning algorithm suitable for low-cost indoor or urban pedestrian navigation application. The sensor fusion was applied to increase the localization accuracy. Due to required low application cost only low grade inertial sensors and wireless network based ranging were taken into account. The wireless network was assumed to be preinstalled due to other required functionality (for example: building control) therefore only received signal strength (RSS) range measurement technique was considered. Wireless channel loss mapping method was proposed to overcome the natural uncertainties and restrictions in the RSS range measurements. The available sensor and environment models are summarized first and the most appropriate ones are selected secondly. Their effective and novel application in the navigation task, and favorable fusion (Particle filtering) of all available information are the main objectives of this thesis. Tato práce se zaměřuje na vývoj navigačního algoritmu pro systémy vhodné k lokalizaci osob v budovách a městských prostorech. Vzhledem k požadovaným nízkým nákladům na výsledný navigační systém byla uvažována integrace levných inerciálních senzorů a určování vzdálenosti na základě měření v bezdrátových sítích. Dále bylo předpokládáno, že bezdrátová síť bude určena k jiným účelům (např: měření a regulace), než lokalizace, proto bylo použito měření síly bezdrátového signálu. Kvůli snížení značné nepřesnosti této metody, byla navrhnuta technika mapování ztrát v bezdrátovém kanálu. Nejprve jsou shrnuty různé modely senzorů a prostředí a ty nejvhodnější jsou poté vybrány. Jejich efektivní a nové využití v navigační úloze a vhodná fůze všech dostupných informací jsou hlavní cíle této práce.

Modern wireless technologies didn't avoid smart metering as an integral part of smart grids. They have a high flexibility and can be easily integrated into existing installations, it is feasible to use them for communication with meters. The goal of this paper is to give awareness of commonly used protocols/technologies in smart metering, provide basic characteristics of them and describe their deployment in smart grids and the consequent advantages/disadvantages.

Prepaid energy meters are relatively widespread in the world. These meters allow for distribution of electricity in developing and politically unstable countries. In developed countries, prepaid meters help distributors to solve problems with defaulters and they help underprivileged customers to better control the finances spent on consumption of energy. Currently smart metering technologies are being tested and introduced on the market. The Smart Meters bring significant changes in the measurement and billing of energy consumption. This paper deals with possible solutions for prepaid energy in the smart metering age.

With decreasing price and growing computational power FPGAs become interesting solution for growing set of embedded applications. It is often considered competitor for MCU or ASIC based solutions, mainly for their good ratio of computational capacity to price and its flexibility. Unfortunately the FPGA technology has some specifics that complicate their deployment in systems with requirements on high reliability and safety integrity. The most severe reliability issue is susceptibility to radiation induced errors. This paper introduces to this problem, techniques that are used to cope with it and gives comparison to MCU based solution.

Industrial automation has been dominated by fieldbuses for several decades. Legacy fieldbuses, such as Profibus, were able to provide the required functions, as they were precisely tailored to automation needs. Fieldbuses represent a complex communication solution for automation, and they define automation-specific physical and link layers and a dedicated communication object model. Nevertheless, Ethernet-based communication ubiquitously appearing in offices fostered temptations to bring Ethernet to production. Ethernet provides market-proven cost-effective hardware components with high data rates and immense integration and network management support using the overlaid management protocols. However, Ethernet has not been designed for industrial applications and would fail to fulfill requirements of industrial automation in its generic form. Hence, adaptations in both end devices and sometimes even switching devices had to be carried out. Finally, various industrial requirements were met, and Ethernet-based fieldbuses became state-of-the-art technologies competing with legacy fieldbuses.

The paper presents description of three different protocol gateways for interfacing HART pressure sensors. The gateways have been designed, programmed and realized as hardware prototypes. The first gateway is a wireless transducer between the HART interface of the sensor and a Bluetooth network. The second gateway connects the sensor to an Ethernet network with Modbus protocol. The third gateway is a wireless transducer for ZigBee networks. The gateways are based on embedded microcontrollers with the required interfaces. The software implementation is done in C using protocol libraries. Hardware and enclosure are designed for industrial applications. The gateways are adapted for use with HART pressure sensors.

The paper describes results of analysis of interoperability issues encountered when interconnecting systems that use heterogeneous communication interfaces. The initial analysis has been focused to issues faced when interconnecting heterogeneous fieldbuses. However the results obtained from the study are generally applicable to all systems that need to exchange information through incompatible interfaces using a broker that transforms data from one interface to the other. However, the research has shown that many interoperability problems can be eliminated by use of common concept for expression of sensor data regardless of the protocols used for the actual data exchange. The root cause of interoperability problems has been identified in the heterogeneity of concepts used for description of the reality. The authors argue, that common concept for sensor-actuator networks (SANETS) is needed to prevent unnecessary interoperability problems especially when building platforms for generic SANETS.

This paper describes security features of Bluetooth PAN wireless network. Security aspects are explained step-by-step from the basic items and key management to the authentication and data encryption. Finally, current problem with the Bluetooth security are presented.

The ZigBee communication standard is intended for use in various applications. Specific one is the building automation. Here plays an essential role the radio range in the building environment. As the propagation of the radio signal inside a building is almost impossible to be calculated, some practical tests have been conducted. The concept of the tests and the most important results are shown in this paper.

Contribution deals with recent development in smart sensors that are widely used all over automation projects. Authors present design and development of Internet oriented data concentrator as well as world first Internet oriented single pressure sensor with Ethernet 10BaseT interface, indicate and discuss problems with implementation of advanced communication technologies in industrial area. In the next part of the paper there are presented solutions of indicated problems by author’s own design and development. Second part of the paper deals with wireless technologies for automation purposes. Authors present a unique smart pressure sensor communicated by wireless Bluetooth technology with PDA and Smart Phone.

The paper shows the challenges associated with attempts to utilize Bluetooth communication interface for automation purposes like control and data acquisition. The paper describes major challenges, selected approach, first tests, first experiences with Bluetooth on Linux and first prototypes of embedded devices used for testing. Moreover the paper discusses some specific challenges associated with utilization of wireless communication techniques (with focus to Bluetooth) in automation. Finally the paper presents ideas (formal methods) that could be used to analyze, and improve reliability of such system, and approach (time triggered approach with clock synchronization) that could be used to improve the deterministicity of wireless communication channels.

Most power line communication (PLC) models are designed to date simulate power lines as two-wire lines. However, in alternating current (AC) electrical distribution, the two-wire option is seldom applied, and medium-voltage lines are most often based on the three-phase configuration. In this context, the influence of the ground, which constitutes another conductor with specific parameters, cannot be neglected. Two-wire models are characterized by limited accuracy, not allowing us to simulate certain major phenomena affecting PLC. This, for example, could embody the answer to the question of whether it is more advantageous to transmit a signal independently through each phase, reference the signal with respect to another phase or to use the ground as a reference. This paper discusses a multi-conductor model that eliminates the disadvantages outlined above; the proposed model exploits the multi-conductor telegrapher’s equations. In order to be able to include medium-voltage (MV)/ low-voltage (LV) transformers in medium-voltage network models, we constituted a transformer model. The designed models were validated on a real medium-voltage network. To be able to evaluate the suitability of the PLC, the noise in the medium voltage network was measured in order to determine the signal-to-noise ratio (SNR).

One of the most important components of recent automation systems of machines, production lines and technological processes is the communication subsystem. Instead of parallel bus connections, the serial buses on various hierarchical levels of control structures are used. This contribution deals with problems of implementation of serial communication buses in a heterogeneous control instrumentation environment in industrial plants. It presents an aid for dealing with such problems on basis of a laboratory of industrial automation with heterogeneous communication testbed.

This paper deals with the utilisation of Ethernet based system directly on the sensor bus level. It describes several problems encountered when designing a sensor with embedded Ethernet interface. A realisation of such sensor is described.

Nowadays ontologies are more and more often put on work in diverse industrial areas thanks to their high potential of applying. In this paper we extend work of other developer groups that are interested in ontologies and purvey frameworks for ontology using. To make clear meaning of ontology, we describe it with a set of properties that points out its diversity. Next we focus on possibilities of using ontologies in diagnostic systems with emphasize of interoperability. We illustrate several scenarios for engaging ontologies into these systems for sharing diagnostic datasets or terms meanings of dynamical systems that cause their better understanding and manipulation with them. Each scenario include role of ontology and a list of advantages that ontology implementation brings.

The paper deals with Smart Grids. After slight introduction, the Home Area Network is described. The paper focuses on the device called Home Coordinator. The Home Coordinator controls all home appliances in the home with respect to reach their maximum efficiency and cost saving. A basic approach and algorithm to schedule home appliances is presented.

We consider the problem of implementing security algorithms into embedded systems deployed in automation applications. Such systems are typically built on embedded microcontrollers with limited resources and as hardware changes may not be possible or convenient, the software based cryptography is a suitable solution. In this paper we present results of performance benchmarks of different software-implemented symmetric cryptography algorithms on 8 and 16-bit microcontroller platforms. The contribution of the work is in comparing performance of different algorithms, embedded microcontroller platforms, effects of optimizations and different implementations.

Traditional way of interconnection of industrial fieldbuses is used for data acquisition and operator control. This type of interconnection is not suitable for realtime control as it usually uses MS Windows based software gateways that are not capable of real-time processing of information. To assure real-time data transfer it is necessary to use different principle of interconnection. This new approach is based on hardware gateways. Hardware gateways can transfer data in predictable time. At present time hardware gateways are already used to interconnect fieldbuses of different level. Our paper presents that it is possible to use hardware gateways to interconnect fieldbuses of same level.

The objective of our work is to provide industrial communication based on IP networks with an increased level of determinism and reliability compared to the office IP networks. Our approach is based on the established methods of Quality of Service used in telecommunication networks and verification of our approach by both empirical and analytical means. In this paper, we propose an extension of Network Calculus in form of Rate-Variable-Latency (RVL) service curve which is capable of modelling of step changes of latency during data congestions caused by flow aggregation. Furthermore, we introduce several properties of the RVL service curve. Finally, we provide a comparison of the outgoing port congestion simulation using the RVL service curve and our empirical measurements.

This paper describes security features of ZigBee and Bluetooth PAN wireless networks. On examples of those two wireless systems are demonstrated challenges associated with utilization of present wireless systems for applications requiring secure data exchange. Recent penetration of wireless technologies into building and process automation applications even increases the need to fully understand the limitations of the security concepts used.

A smart pressure sensors equipped with wireless communication interface (Bluetooth) and Ether- net/Internet communication capabilities have been devel- oped. The smart pressure sensors are based on a LMK351 standard pressure sensor. The presented sensors represent new family of products with state-of-the-art communication interfaces.

The paper shows the challenges associated with attempts to utilize Bluetooth communication interface for automation purposes like control and data acquisition. The paper describes major challenges, selected approach, first tests, first experiences with Bluetooth on Linux. and first prototypes of embedded devices used for testing. Moreover the paper discusses some specific challenges associated with utilization of wireless communication techniques (focused to Bluetooth) in automation. Finally the paper presents ideas (formal methods) that could be used to analyze, and improve reliability of such system, and approach (time triggered approach with clock synchronization) that could be used to improve the deterministicity of wireless communication channels.

The demand for integration of all levels of plant control into a single system has been increasing during last years. However the plants have been built on heterogeneous communication technologies that use various approaches for representation of data. Heterogeneity of the plants is faced using combinations of various software and hardware gateways. The presented paper describes why the use of gateways is not a good solution in general, and presents a technology that can be the ultimate solution of interoperability issues in automation. The paper presents disadvantages of gateway based interoperability solutions in heterogeneous control environments and emphasizes possible interoperable solution. The proposed solution is based on emerging open technologies that promise to deliver interoperable services for exchange of all kinds of data among computer systems without the need to perform frustrating conversions between disparate protocols and incompatible data structures. Moreover the proposed interoperability solution will guarantee both interoperability in the field of process automation, and interoperability with future applications of ubiquitous computing too. Disadvantages of proposed solution compared to present communication technologies are mentioned as well.

Paper deals with two significant trends in the automation and control theory of the last decade. The problems are evoked by a lack between control theory and the automation praxis in the case of Networked Control Systems (NCS) and by penetration of wireless communication used in case of Sensor Networks. Authors define serious theoretical problems in Networked Control Systems analyses in the design of digital control such as non-periodical sampling period, variable delays in control feedback, lower dependability of feedback information and some other issues. Network Calculus is proposed as a possible mathematical and description tool. The paper also mentions an ambitious research program of the Deutsche Forschungsgemeinschaft to develop new theory of the NCS synthesis. In the second part of the paper the Sensor Networks as the new phenomenon in process values measurement and data acquisition systems are described. It is the opinion of the authors, that sensor networks represent totally other look on the utilization of sensors, than represents classical measurement engineering used in data acquisition systems.

Paper deals with existing situation in industrial communication. Apart from proprietary serial communication systems exist many standardized fieldbuses. Due to increasing requirements on rapid data transfer and in hope of better transparency of communication in the overall plant control architecture, Ethernet has established as a well known and broadly used industrial communication technology. The paper shows one of possible methods for at least partial overcoming of the existing heterogeneity and incompatibility in large highly distributed control applications. The way is virtual automation networks and paper specify requirements and key features of the solution. The most important part of the paper deals with questions of the real - time features of virtual automation networks and the data security in heterogeneous communication environment.

The aim of the paper is creation of an easily interpretable model of human driver during a simulated elementary car driving task. This is achieved using a Hammer- stein model whose non-linearity is modelled by a simple Mamdani fuzzy system. Derived closed form formulae of the model are employed to facilitate convergence of the iden- tification algorithm and render it more accurate. The experimental results suggest that the method is suitable for modelling of lane changing manoeuvres on a motorway.

With increasing oil price and environment pollution, especially in large cities, electric vehicles are getting to be more interesting than they were several years ago. Using electric vehicles in cities and large agglomerations lead to less pollution caused by common cars combustion engines (nitrogen oxides, carbon oxides, dust particles). Electric vehicles are more considerate to the environment than traditional cars even when the energy produced by non-renewable energy resources is used for their charging. The lack of the infrastructure prevents electric vehicles spreading. This paper describes standards and ideas how to integrate electric vehicle charger to the home area network. Home area network is a local part of SmartGrid network usually situated in homes. All devices connected to this network should implement several specifications. Basic requirements to charger properties are summarized.