Ing. Jan Sobotka, Ph.D.

COVID -19 pandemic and its restrictions bring new challenges to all aspects and phases of higher education. At universities, new remote formats have been developed and deployed for lectures and laboratory exercises. This article addresses challenges and introduces the new experience with lectures and laboratory classes during the pandemic time at the Department of Measurement of the Czech Technical University in Prague, Faculty of Electrical Engineering. Based on the student survey of more than 250 students describes the possibilities of how to adapt the lectures during the lockdown. The article also introduces the Home Lab, a tool developed in the department that helps in distance teaching practical electronic classes. Home Lab includes two parts with functional groups, a Laboratory Experimental Device and a System of Measurement Instruments. The article also shows the opportunity for suitable remote exercises and variants of circuits that can be easily assembled and measured using Software Defined Instrument based on various microcontrollers. A detailed description of all Software Defined Instruments is also present. During the Pandemic, the home lab model was successfully practically verified during distance learning in three subjects, with more than 150 students per semester. It has also been shown that the Home Lab can be successfully deployed for a semester project. The article also presents experience with the teaching software-oriented courses. At the end of the article, practical knowledge and an experience from distance teaching during a three-semester lockdown are shared.

Výzkumná skupina zaměřená na problematiku automobilové elektroniky a vozidlových komunikací se zformovala na katedře měření ČVUT FEL na přelomu století pod vedením doc. Petra Kocourka. Celá její existence je spojena s úzkou a dlouhodobou spoluprací s několika odděleními vývoje Škody Auto, takže lze říci, že veškeré výsledky výzkumu a vývoje jsou vzápětí aplikovány v praxi. Spolupráce se zaměřuje zejména na problematiku automatizovaného testování, která v současné době nabývá na významu vzhledem ke stále se rozšiřujícímu portfoliu uživatelských funkcí vozidel, jízdních asistentů, informačních a komunikačních systémů apod. Během uplynulých více než 20 let bylo navrženo a realizováno několik generací automatizovaných testerů chování řídicích jednotek vozidel na vozidlových sítích CAN a LIN; v rámci jejich vývoje byly vyvinuty a následně publikovány unikátní měřicí metody.

Pandemie COVID-19 prakticky přes noc dramaticky změnila nebo dokonce dočasně zastavila výuku na mnoha univerzitách. Tato situace byla výzvou zejména pro technické univerzity s původně spoustou praktických činností a laboratorních cvičení, protože vyžadovala vytvoření stabilního a plnohodnotného online vzdělávacího systému. Vše, co dosud probíhalo formou přímého kontaktu, od samotných přednášek, seminářů, praktických ukázek a laboratorních cvičení, přes písemné testy až po ústní zkoušky, bylo nutné převést do digitální podoby, o dalších právních a administrativních procesech pro zajištění výuky nemluvě. Významnou výhodou FEL ČVUT bylo, že drtivá většina pedagogů již měla předchozí zkušenosti s poskytováním online vzdělávání a disponovala řadou nástrojů, které bylo možné k tomuto účelu použít. Rychlý přechod z prezenční formy studia na distanční nicméně vyžadoval přehodnocení koncepce organizace výuky a zajištění řady souvisejících činností, zejména v oblasti komunikace, plánování vzdělávacích aktivit a výběru vhodných metod.

Covid-19 related restrictions bring new challenges to all aspects and phases of higher education. At universities, new remote formats are deployed or even developed both for lectures and laboratory exercises. This article addresses new challenges and describes the experience with lessons during the pandemic time at the Department of Measurement of the Czech Technical University in Prague, Faculty of Electrical Engineering. It introduces the best practices exercised using the Home Lab, which helps in distance teaching of practical electronic classes. Home Lab includes two models with functional groups, a Laboratory Experimental Device and System of Measurement Instruments. The article also shows the possibilities of suitable remote exercises and variants of circuits that can be easily assembled and measured using Software Defined Instrument based on STM microcontrollers. During the pandemic, the home lab model was successfully practically verified during distance learning in three classes, with more than 150 students. The article also presents experience with the teaching of software-oriented courses. At first glance, their transformation can be viewed as straightforward. However, practical realization reveals few remarkable details.

This paper deals with problematics of structure of Timed Automata models suitable for Model-Based Testing of automotive systems. Previous ex-periments, primarily focused on the environmental models, have shown that their structure does not significantly affect the coverage speed of testing process. How-ever, similar questions regarding the observer part of the system model remained open. This paper analyzes those remaining questions and focuses on uncovering possible relation between an observer model structure and the quality of gener-ated test sequences according to multiple criteria. Goal of presented experiments is to compare multiple modeling approaches and discover which one is most suit-able for automotive systems.

This paper aims to present a software facility designed to accompany the currently developed automotive radar target simulation platform. This simulation platform, together with the software facility presented in this paper, is envisioned to confront recent challenges introduced by rising complexity of radar-based automotive systems. The presented software facility allows to easily control the companion target simulation platform and design traffic scenarios for the radar testing. The trajectory design used by the app is implementation-agnostic and is based on the interpolation of linear trajectory segments with selectable velocity profiles. That enables future integration of the platform into the testing process and virtual reality-based testing platform.

Radar sensors are becoming standard equipment in modern cars. They are an integral part of systems for blind-spot detection, adaptive cruise control, or emergency braking. All these systems have to be thoroughly tested to achieve a high-quality standard of produced vehicles. One of the commonly adopted techniques is Hardware-in-the-Loop testing. A Radar sensor-based systems Hardware-in-the-Loop testing requires the capability of simulation a target to the sensor. The paper presents a purely digital approach to simulation of static as well as moving target (E.g., car) to an automotive radar sensor. The absence of analog or mechanical parts significantly reduces the solution costs.

Adaptive Random Prioritization is a Test Case Prioritization technique which orders test cases within a test suite with a goal of earlier fault detection using a semi-random heuristics. Compared to other Test Case Prioritization methods, Adaptive Random Prioritization has only an average fault detection performance. However, it is less sensitive to some test suite features which negatively affect fault detection performance than other TCP techniques due to its semi-random nature. The article proposes an improved version of Adaptive Random Prioritization technique. The key idea behind the presented enhancement is to extend the test case selection process with additional information about control flow and change of test statements coverage of a test suite. The enhancement replaces the original Test set distance function with a Multi-Criteria Decision-Making method. Validity of the proposed method is evaluated on data from six embedded systems. The evaluation criterion is fault detection performance expressed by Average Percentage of Faults Detection metric and Â12 statistic. The proposed improvement achieved better fault detection performance for all examined systems.

This paper is focused on particular issues related to the modeling of automotive systems as a network of timed automata. During experiments with application of the Model-Based Testing on automotive systems, a few modeling related inquiries were raised. This paper analyzes the question of influence of an environment model complexity on the coverage of an observer part of a system model. The goal is to uncover, which modeling approach is most suitable for the environment models.

Deployment of the Model-based Testing methods in practice has not achieved the level it deserves. To help dissemination, as well as to improve the testing process in a particular domain, this paper presents a new Test Generation tool on a case study. The domain is automotive integration testing. The new tool is named Taster and utilizes Timed Automata for the online Model-based test generation. The objective of these tests is testing of integration of automotive comfort systems. The proposed concept, the system modeling, and the new software tool is evaluated on testing of a Keyless Access System. Purpose of the paper is to present an approach for automatic test generation intended for automotive integration testing.

Network operation of FlexRay Electronic Control Unit (ECU) in passenger cars is influenced by the significant number of parameters that have to be written into the ECU FlexRay controller. To keep the FlexRay network robust, the correct parameter values must be set in all ECUs of the FlexRay communication cluster. This is not a trivial task since particular ECUs are supplied by different manufacturers and any manufacturer can change some parameter either by mistake or even intentionally. The effect of such a change is generally unpredictable and can often be observed under specific operational conditions only. The most serious effect is a global FlexRay network failure, which usually leads to the fatal vehicle malfunction. Hence it was necessary to develop, implement and validate new dedicated measurement methods, enabling the evaluation of actual values of the most critical FlexRay parameters at the Open Systems Interconnection (OSI) data-link layer and thus the ECUs individual acceptances testing for system integrator verification purposes. As the mass production of FlexRay controllers is not applicable due to a lack of test specific features, deployment of these methods is enabled by utilization of unique FPGA-based FlexRay controller implementation. Proposed measurement methods are focused on parameters specifying the FlexRay wakeup protocol, FlexRay startup procedure, and the FlexRay synchronization mechanism. Each measurement method is described in detail, including its limits and prerequisites. All the developed methods were validated by experiments on real FlexRay networks and results are included in the paper. Two different types of FlexRay controller core (Freescale and Bosch E-Ray) were used in ECU under test (EUT) to eliminate the risk of measurement method dependence on a specific controller implementation.

Model oriented testing methods are known relatively long time, but the right time for viable deployment is coming up now with the continuously growing amount of vehicle electronic systems. Paper proposes a new Model-Based Testing approach to testing of automotive electronics systems. The key concept is the utilization of Timed Automata for online testing of automotive electronic control units. System modeling, the new tool, a bit of necessary technology and preliminary results intended to identify future research goal are presented.

Goal of this paper is to propose an improvement of an automotive distributed system testing process, namely the part called integration testing. The improvement is focused on test cases development, which is today done mostly manually by test engineers. The work is focused on deployment of Model-Based Testing method on field of integration testing.

FlexRay is an incoming communication standard for automotive applications. Paper deals with an implementation of unique FlexRay communication controller in FPGA and shows examples of its usage for FlexRay Wakeup and Startup configuration parameters evaluation.

FlexRay is an incoming standard of automotive distributed system intended for safety critical applications like x-by-wire. The first part of the chapter provides an introduction to the FlexRay standard, presents an analytic model of FlexRay Synchronization Mechanism, validation of this model and offers its usage for measurement of parameters of synchronization mechanism in real FlexRay networks. The second part of the chapter presents a case study of FlexRay application in a distributed implementation of ABS (Anti-lock Braking System) in vehicle. The anti-lock braking system is nowadays a part of almost every vehicle. In order to work properly, the anti-lock braking system needs to have actual information about the rotation of every wheel. Currently, the information about the frequency of wheel rotation is being transmitted via the current loop. This paper describes a method, where the information from the rotation sensors of the wheels is transmitted into the control unit through the FlexRay bus. Additional wireless acceleration sensors located on the wheels are used to improve the ABS performance.

For FlexRay fault free communication it is necessary to ensure correct parameterization of each network node. This paper describes methods for evaluation of basic internal timing parameters of a single FlexRay node. Methods reflect common situation in automotive industry, where each electronic control unit comes from different manufacturer. No direct access to ECUs actual parameters is usually available, thus the independent methods to validate specific parameters are needed.

FlexRay is an incoming standard for automotive distributed systems. For safety critical applications like x-by-wire systems it is necessary to develop techniques for their verification and validation. This paper presents a model of FlexRay Synchronization Mechanism, validation of this model and offers its usage for validation of parameters of synchronization mechanism in real FlexRay networks.