Oto Haffner
@stuba.sk
Associate professor, Faculty of Electrical Engineering and Information Technology of STU in Bratislava
Slovak University of Technology
I am a young researcher and educator working on applications of computer and machine vision in mechatronic systems using modern ICT such as microcomputers, cloud, computational intelligence, etc. My current focus is on the use of deep learning in practical applications for Industry 4.0 such as visual quality control. I am also involved in modelling and simulation of production processes in manufacturing. I have experience in leading research teams in domestic projects. I have been responsible for 2 projects of the Young Researchers Support Programme. I was in the position of deputy head of the KEGA project, which ended with an excellent evaluation and the societal benefit of its results was stated. Currently, I am also the deputy project leader of a KEGA project. In addition to my professional interests, I am also interested in multimedia, film, video, photography and 3D graphics.
EDUCATION
Third level of higher education (PhD.)
Faculty of Electrical Engineering and Information Technology STU in Bratislava [ 2013 – 2016 ]
study programme Mechatronic Systems
Second degree of higher education (Ing.)
Faculty of Electrical Engineering and Information Technology STU in Bratislava [ 2011 – 2013 ]
study programme Robotics
First degree of higher education (Bc.)
Faculty of Electrical Engineering and Information Technology STU in Bratislava [ 2008 – 2011 ]
study programme Industrial Informatics in the combination of the fields of study Automation and Applied Infrormatics
RESEARCH, TEACHING, or OTHER INTERESTS
Computer Vision and Pattern Recognition, Artificial Intelligence, Industrial and Manufacturing Engineering, Control and Systems Engineering
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Filip Žemla, Ján Cigánek, Danica Rosinová, Erik Kučera, and Oto Haffner
MDPI AG
We are now living in a time when the fourth industrial revolution is bringing new technologies with intensive digitalization of all levels of production. This paper presents a complex solution for the monitoring, diagnosis, and control of the production process, in our case, discrete event systems. The proposed solution—a mechatronic platform—further develops and extends our recent results where the overall concept was outlined and some partial tasks were studied. The present paper provides the complete structure of the proposed platform together with implementation details for all functionalities. The developed platform uses the latest technologies, such as OPC UA; industrial communication and visualization protocols and tools; and augmented reality, which enables comfortable interaction with real processes. The laboratory-scaled case study shows the qualities of the proposed solution.
Filip Žemla, Ján Cigánek, Danica Rosinová, Erik Kučera, and Oto Haffner
MDPI AG
This paper presents a proposal of a complex mechatronic system that enhances the effectivity of obtaining energy from renewable resources. The main focus is on the photovoltaic energy system, which obtains electricity from the conversion of solar radiation through photovoltaic crystalline silicon-based panels. The design of the complex mechatronic system consists of several steps. The structural design of the photovoltaic panel positioning unit in the form of a three-dimensional model is made in the selected modelling programming environment. Subsequently, a propulsion system is proposed for the designed structure, the functionality of which is verified in the programming environment Automated Dynamic Analysis of Mechanical Systems. The control system design using a programmable logical controller is also presented. The corresponding control algorithm is designed in the programming environment Step7 and covers the optimal positioning of photovoltaic panels. The developed application in the WinCC environment provides a visualization of the positioning control process. The conclusion is devoted to the assessment of the obtained results for the proposed complex mechatronic system for photovoltaic panel positioning in comparison with photovoltaic panels in fixed installation. The presented results were obtained by simulations.
Michal Balla, Oto Haffner, Erik Kučera, and Ján Cigánek
MDPI AG
In today’s industry, the fourth industrial revolution is underway, characterized by the integration of advanced technologies such as artificial intelligence, the Internet of Things, and big data. One of the key pillars of this revolution is the technology of digital twin, which is rapidly gaining importance in various industries. However, the concept of digital twins is often misunderstood or misused as a buzzword, leading to confusion in its definition and applications. This observation inspired the authors of this paper to create their own demonstration applications that allow the control of both the real and virtual systems through automatic two-way communication and mutual influence in context of digital twins. The paper aims to demonstrate the use of digital twin technology aimed at discrete manufacturing events in two case studies. In order to create the digital twins for these case studies, the authors used technologies as Unity, Game4Automation, Siemens TIA portal, and Fishertechnik models. The first case study involves the creation of a digital twin for a production line model, while the second case study involves the virtual extension of a warehouse stacker using a digital twin. These case studies will form the basis for the creation of pilot courses for Industry 4.0 education and can be further modified for the development of Industry 4.0 educational materials and technical practice. In conclusion, selected technologies are affordable, which makes the presented methodologies and educational studies accessible to a wide range of researchers and solution developers tackling the issue of digital twins, with a focus on discrete manufacturing events.
Lukáš Beňo, Rudolf Pribiš, Erik Kučera, Oto Haffner, Martin Pajpach, and Ján Baranovič
IEEE
Enlightenment about containerization is crucial for staying up-to-date with modern software development practices. It enables effective utilization of container orchestration platforms, efficient application deployment and management, enhanced portability and scalability, cost savings, and future technology adoption. However, the integration of containerization education in universities is often limited, highlighting the need for educational resources to bridge this knowledge gap. To address this gap, this work aims to create a web application dedicated to promoting awareness and providing educational resources on containerization.
Oto Haffner, Erik Kučera, Lukáš Beňo, Rudolf Pribiš, Matin Pajpach, and Dominik Janecký
IEEE
Human-robot interaction (HRI) is the study of how humans interact with robots and how to design robots that can interact effectively with humans in a wide range of environments. The aim of this work is to design and implement an HRI system that uses motion capture suit and artificial neural networks to recognize dynamic gestures for improved user interaction. The design of the system takes the form of a simple graphical user environment application, in which the user sees his own movement in real time, also with the prediction of the gesture performed. The work laid the theoretical and practical foundation for future research in the area of reading motion data from mocap suits for the purpose of dynamic gesture detection. The contribution can be used in the design and implementation of other HRI systems in the future.
Rudolf Pribiš, Oto Haffner, Lukáš Beňo, Dominik Janecký, Erik Kučera, Martin Pajpach, Adam Juriš, Michal Hamrák, and Šimon Zajac
IEEE
This document deals with the challenges in the teaching process that must respond agilely to the challenges of technological advances and other unexpected stimuli (the recent COVID pandemic, assertion of power interests, etc.). It confronts the terms Industry 4.0 and Industry 5.0 and illustrates the importance of interoperability and enumerates the technologies to achieve it. It also presents an experimental platform for Industry 4.0 that addresses several Industry 5.0 challenges at the Institute of Mechatronics at the Slovak Technical University in Bratislava. It explains the importance of teaching Industry 4.0 technologies as a whole and introduces the development of an e-learning web application as a way of learning the necessary skills and shares its benefits and results.
Erik Kučera, Oto Haffner, Lukáš Beňo, Rudolf Pribiš, Martin Pajpach, and Dominik Janecký
IEEE
This paper deals with the interfacing of open-source PLC (Programmable Logic Controller) with augmented reality. The goal is to create an interactive environment for monitoring and control of automation processes. Creating new types of human-machine interfaces (HMIs) is one of the challenges of the Industry 4.0 concept and also relates to the Industry 5.0, which is the coming revolution to be human-centric. The practical part of the project focuses on the implementation of interfacing between PLC and augmented reality using OPC UA (Open Platform Communications Unified Architecture) and MQTT (MQ Telemetry Transport) interfaces. The work results in creation of working prototype that uses 3D engine Unity and ARCore library to create an interactive augmented reality environment.
Zuzana Záňová, Vladimír Kutiš, and Oto Haffner
IEEE
The paper deals with the modeling of the vehicle suspension, which consists of dampers, springs, and tires. The paper focuses on the dynamic analysis of vertical vibration of the suspension, which is described by a mathematical quarter car model. The suspension model is excited by stochastic road profiles. Spectral responses are obtained from the quarter car suspension model through the solution of differential equations. The objective of this paper is to evaluate conventional passive suspension in terms of ride comfort, which affects the passengers in the vehicle, and also in terms of road holding, which impacts safety. The article presents the relationship between comfort and road holding of the vehicle. This relationship assesses suspension from both perspectives and shows that increasing comfort and road holding simultaneously are conflicting objectives.
Martin Pajpach, Ľubos Sekerák, Erik Kučera, Oto Haffner, Rudolf Pribiš, Lukáš Beňo, and Dominik Janecký
IEEE
Food waste has been a major challenge in recent decades, with up to 1.3 trillion tonnes of food waste produced annually. With the advent of modern technologies and apps such as Exspiro, which make it easier to manage food in the home, there is an opportunity to reduce this unnecessary food waste. The app offers, among other things, several functionalities that are designed to lead to sustainability - notifying the user of the impending consumption of food, recipes with such food, and also a statistical module that informs the user what food is wasted the most in the household.
Dominik Janecký, Erik Kučera, Oto Haffner, Juraj Kišš, and Martin Pajpach
IEEE
This work focuses on the research, design and development of an application that enables collaboration with a software framework for robots. Foxy Fitzroy's Robot Operating System 2 was used as the robot software framework and Gazebo - Classic was used to simulate the robot. In the introduction of the paper we will discuss the problem analysis, history and applications. Later in this work we will analyze the hardware that is already in use, analyze the solutions that are now on the market, and then the actual design and implementation of the solution. The result of our work is a fully functional application that can be used to demonstrate the three interface options that work with ROS 2.
Martin Pajpach, Rudolf Pribiš, Peter Drahoš, Erik Kučera, and Oto Haffner
IEEE
The development of Industry 4.0, especially in the areas of interoperability and the design, implementation and use of digital twins, has been enormous in recent years. This article discusses three key aspects that Industry 4.0 brings with it - virtualization through digital twins (DTs), interoperability based on the OPC UA standard, and the use of Industry 4.0's Administration Asset Shell (AAS) components. For the purpose of development and education, a design of an education and development platform has been developed, in which these key attributes of Industry 4.0 are conveniently combined into a single entity.
Erik Kučera, Oto Haffner, Peter Drahoš, and Ján Cigánek
MDPI AG
The current trend in industry is the digitalisation of production processes using modern information and communication technologies, a trend that falls under the fourth industrial revolution, Industry 4.0. Applications that link the world of information technologies (IT) and operational technologies (OT) are in particular demand. On the basis of information from practice, it can be stated that there is a shortage of specialists in the labour market for the interconnection of PLCs with information and communication technologies (cloud, web, mobile applications, etc.) in Slovakia and neighbouring countries. However, this problem is beginning to affect other countries in Europe as well. The main objective of the work was to prepare case studies suitable for educational purposes, which would address the modelling and control of a virtual discrete-event system using a PLC program and its subsequent interfacing to a cloud application. Within the scope of the work, three case studies were prepared to demonstrate the control of discrete-event system using different programming systems and their communication with the developed cloud applications. These applications are to be used for data monitoring and emergency intervention of the discrete-event system. The characteristics of the prepared case studies, which combine operational and informational technologies, predestines them for use in the sphere of education of engineers for digitalisation of production processes. They can also be helpful in research on the creation of digital twins, which represent a type of symmetry between real and virtual systems.
Erich Stark, Oto Haffner, and Erik Kučera
MDPI AG
This paper is focused on the possibilities of data collection via photogrammetry methods, using smartphone cameras and post-processing. The aim of this paper is to refer to progressive technologies that are part of smartphone devices, which bring more performance and variability of usage year by year. The theoretical part starts with looking to the past, describing problems of measurements and solutions invented by famous mathematicians, which we use nowadays. The following section deals with the background of measuring the human body and photogrammetry. The next section is about measuring and using calibration methods. The results section presents the architecture design of the system and a visual representation of how the application works. The result of processing a 3D person is a data object with measurements in real world metric units with minimum deviation. The conclusion is that we created our own low-cost method for 3D body measurement which partially or completely removes the shortcomings that were identified during the review of similar solutions. Our method is based on the use of open-source libraries, the use of a single smartphone mobile device and the creation of a true 3D human body model.
Erik Kucera, Oto Haffner, Peter Drahos, and Alena Kozakova
Institute of Electrical and Electronics Engineers (IEEE)
Discrete event system is a type of system, which changes its state based on asynchronously occuring events. One of many approaches of describing this category of systems is a mathematical formalism called the Petri Net. This article introduces an original software solution, leveraging the graphical representation of this formalism in conjunction with the communication standard OPC Unified Architecture. This combination enables the user to model and control discrete event and hybrid systems using an intuitive, user-friendly graphical interface. The software application also brings new possibilities into scope of this academic domain due to the implementation of a Petri Net formalism extension - continuous elements, which greatly expands the area of systems, which can be modelled and controlled using this tool. The developed software tool was successfully verified in control of a virtual systems. Offering a graphical environment for the design of discrete event / hybrid system control algorithms, it can be used for education, research and practice in cyber-physical systems (Industry 4.0).
Peter Drahos, Erik Kucera, Oto Haffner, Rudolf Pribis, and Lukas Beno
IEEE
The article presents a short review in the field of industrial communications and networks, which are key to the digital transformation and the rise of Industry 4.0. It captures the latest developments in communication technologies in three application domains: process automation, factory automation and wireless technologies in industry.
Oto Haffner, Peter Drahos, Fredrik Valocky, and Erik Kucera
IEEE
The aim of this paper is to communicate the partial results of project: Development of an autonomous vehicle using open electric car platform. It presents the requirements for a visual system for an experimental platform of an autonomous electric vehicle. The visual system can be divided into 2 main functions: safety and localization. The article describes the technical specifications for both systems and the experimental results of the systems.
Ondrej Kolimar, Kamil Kusnirak, Erik Kucera, and Oto Haffner
IEEE
Purpose of this paper is to evaluate methods used in management of delivery team in 9 years of practice of a small size software company in Slovakia. First it focuses on summarizing difficulties that arise in this setup and traditional well-known approach on how to overcome it using waterfall or agile methodology approach. Main goal is to emphasize differences between theory and real-world scenarios where no existing methodology fits the criteria for small software project management. Key metrics this paper will focus on is delivery team performance on projects and satisfaction with work on projects. Performance is evaluated based on the historical project data from the company while satisfaction data are derived from the regular employee questionnaire.
Michal Hlavaty, Alena Kozakova, and Oto Haffner
IEEE
Programming is not easy to learn or teach because different students need different explanations to understand such a complex concept. Traditional teaching methods and learning approaches are no longer appropriate for many kids. According to studies, such approaches impair students’ motivation and interest in studying programming. According to research, games can help learn Python programming. The aim of this paper is to present our educational game that we developed in the Unity 3D game engine. The game focuses on pure basics of programming in Python language. Before and after completing the game the player has to fill out a survey that helped us analyze the project.
Erik Kucera, Oto Haffner, and Dominik Janecky
IEEE
In this paper, we will address the issue of digitalisation of various production processes, using modern information and communication technologies. This trend falls under the fourth industrial revolution, Industry 4.0. One of the challenges is the creation of advanced human-machine interfaces (HMIs) for cyber-physical systems. New forms of interfaces can be implemented in augmented reality. The paper therefore deals with the connection of a discrete-event system with 3D engine Unity. 3D engines are used to develop augmented reality applications.
Dominik Janecky, Erik Kucera, and Oto Haffner
IEEE
Almost everyone experiences some form of phobia an overwhelming fear and inappropriate response to particular stimuli - directly or indirectly at some point in their existence. Even those without phobias themselves probably know someone who is affected by them in their daily lives. This article presents a cutting-edge educational tool to control phobia-related dread. Teaching a phobia sufferer to recognize and manage his fear is a crucial part of the therapy process. Utilizing virtual reality software, the client may be exposed to a variety of terrifying events connected to his or her phobia and watch how they affect him or her. This enables a more precise assessment of the severity of the phobia and, as a result, an improvement in patient coaching to control the fear. Another method of treating phobias is augmented/mixed reality. We chose to work with the Microsoft HoloLens 2. Using these glasses, images, videos and 3D models can be displayed and rendered into the participant’s real environment. Which means that the participant can be in contact with their phobia directly in an environment they are familiar with (e.g. their apartment, room, etc). With arachnophobia, spiders can appear all over the floor and walls of his room which would be projected directly in the glasses he would be wearing on his head.
Kamil Kusnirak, Ondrej Kolimar, Erik Kucera, and Oto Haffner
IEEE
This paper provides insights on how to lead projects from different perspectives into successful finale after 10 years of project management of micro software development projects. Considering different roles, experiences and positions on client’s side as well as on delivery partner’s and tracking client’s satisfaction and coverage of expectation over time. Standard methodologies of software development and project management like waterfall and agile combined with tool-based techniques are ineffective on micro projects software project environment by their defaults. Modifications of these approaches are required to achieve a golden ratio between client’s satisfaction and project effectiveness. System of suggested rules should provide better understanding of the client’s true needs, expectations and satisfaction and still cover at least 80% of project plan and budget without any compromises. Rest of 20% situations are considered as unpredicted and unspoken requirements and this paper is also covering the topic.
Erik Kučera, Oto Haffner, Dominik Janecký, and Danica Rosinová
Springer International Publishing
Martin Pajpach, Oto Haffner, Erik Kučera, and Peter Drahoš
MDPI AG
The main purposes of this paper are to offer a low-cost solution that can be used in engineering education and to address the challenges that Industry 4.0 brings with it. In recent years, there has been a great shortage of engineering experts, and therefore it is necessary to educate the next generation of experts, but the hardware and software tools needed for education are often expensive and access to them is sometimes difficult, but most importantly, they change and evolve rapidly. Therefore, the use of cheaper hardware and free software helps to create a reliable and suitable environment for the education of engineering experts. Based on the overview of related works dealing with low-cost teaching solutions, we present in this paper our own low-cost Education Kit, for which the price can be as low as approximately EUR 108 per kit, for teaching the basic skills of deep learning in quality-control tasks in inspection lines. The solution is based on Arduino, TensorFlow and Keras, a smartphone camera, and is assembled using LEGO kit. The results of the work serve as inspiration for educators and educational institutions.
Erik Kučera, Oto Haffner, Peter Drahoš, Roman Leskovský, and Ján Cigánek
MDPI AG
Petri nets are an important tool for creation of new platforms for digitised production systems due to their versatility in modelling discrete event systems. For the development of modern complex production processes for Industry 4.0, using advanced mathematical models based on Petri nets is an appropriate and effective option. The main aim of the proposed article is to design a new software tool for modelling and control of discrete event systems using Arduino-type microcontrollers and code generation techniques. To accomplish this task, a new tool called “PetriNet editor + PetriNet engine” based on Petri nets is proposed able to generate the code for the microcontroller according to the modelled Petri net. The developed software tool was successfully verified in control of a laboratory plant. Offering a graphical environment for the design of discrete event system control algorithms, it can be used for education, research and practice in cyber-physical systems (Industry 4.0).
Frederik Valocký, Peter Drahoš, Oto Haffner, Miloš Orgoň, and Alena Kozáková
IEEE
In this article, we design a road identifier (R-ID). The R-ID must be easily and quickly recognizable by a camera mounted on the vehicle. The camera captures this R-ID and then calculates the position information from it. The article describes the decision-making procedure for the design of an R-ID using camera recognition of geometric shapes. Parameters such as the uniqueness of the R-ID also play a role in this recognition, so that it is not interchangeable with other traffic signs. Another parameter is the percentage needed for the R-ID to be correctly recognized by the camera to obtain the necessary data from the overlay image. The outcome of this article is therefore a road identifier (a pattern) placed on the road which will be captured by the camera mounted on the vehicle.
RECENT SCHOLAR PUBLICATIONS
MOST CITED SCHOLAR PUBLICATIONS
RESEARCH OUTPUTS (PATENTS, SOFTWARE, PUBLICATIONS, PRODUCTS)
Utility models registered:
PUV 148-2021: Method of controlling the vehicle's steering posture and wiring
PUV 156-2020: Handler safety system
PUV 200-2019: Method of monitoring and controlling mechatronic systems using augmented reality and technology assembly
PUV 153-2019 Method for correcting the centre of gravity of a car and wiring
PUV 86-2018: Vehicle remote control method and system
PUV 145-2017: System for visual assessment of Lemna minor growth inhibition in ecotoxicity tests
PUV 129-2017: System for remote automatic quality control of draft beer
PUV 105-2017: System for automatic visual inspection of welds
PUV 68-2017: System integration for control of hybrid systems via microcontrollers with nested logic petri nets
PUV 67-2017: Wiring of system for control of hybrid systems via microcontroller and computer with nested logic Petri nets
PUV 5023-2015: System to protect the driver's vision from being blinded by oncoming vehicles
PUV 5050-2013: Process for creating a wood imitation surface
Patents pending:
P 99-2022: Method for localisation of an autonomous vehicle and integration of a visual system for localisation of an autonomous vehicle
PP 158-2019: Method for monitoring and operating mechatronic systems using augmented reality and technology assembly
Utility models pending:
PUV 127-2022: Method for localisation