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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.

Vehicle safety remains a topic of major interest, and diverse assistance systems are implemented that focus primarily on analyzing the immediate vicinity of the car and the driver’s control inputs. In this paper, by contrast, we emphasize understanding the driver’s control performance via obtaining valuable data and relevant characteristics. To acquire the data, we employed an in-house-designed, laboratory-built vehicle driving simulator. This simulator exploits the Unreal Engine 4 framework to deliver a high level of realism. The fact that the actual designing and associated processes were materialized through our own efforts has brought advantages such as simplified data acquisition, possibility of creating custom scenarios, and modification of the virtual elements according to our specific needs. We also developed an application to analyze the measured data from the perspective of control theory, establishing a set of parameters that provided the basis for an early version of a driver performance index indicator.

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.

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 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.

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.

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.

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.

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.

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.

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.

Band-limited signal extrapolation and spectral super-resolutions are closely related. They both can be achieved using Slepian series. This method is often believed to be dependent on computing definite integrals. Instead of using numerical integration, a simple and reliable method, which can be implemented in MATLAB, is presented. This way, it is much easier to investigated the extent to which a signal can be extrapolated from its samples taken in a finite interval. The proposed method is tested with data from a real microphone array.

This paper describes the creation of a vehicle driving simulator that collects and implements data acquired from a driver’s inputs. These data are stored for future analysis of the driver and his style of driving. The paper explains vital steps of the process such as theoretical background for modelling human behaviour, analysis of typical traffic situations that offer relevant information about a driver, simulator scenarios that reflect such traffic situations and an overview of gathered data.

We discuss the possibility of using simulation technologies for human factor assessment. In this context, a simple car-driving simulator was developed in MATLAB/Simulink. A human driver controls a simulated drive via an input HCI (Human-Computer Interface) device, i.e., a joystick or a steering wheel with pedals, exploiting the perception of the current situation in the visualized scene. To enable the human factor assessment, several testing scenarios were designed and implemented; some of these were subsequently used for measuring the driver’s responses to the simple visual stimuli. We analyzed the acquired data and evaluated the basic parameters of the human operator, such as the reaction delay or the attitude to control. The results indicate the potential for more complex experiments in this field.

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.