
Aleksander NawratSilesian University of Technology · Institute of Power Systems and Control
Aleksander Nawrat
Prof. PhD. DSc. Eng.
About
150
Publications
21,597
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
963
Citations
Introduction
CyberSecurity , AI , Quantum Calculations
Publications
Publications (150)
This paper presents the developed device created for detection and tracking of people and their faces and temperatures. The solution does not require internet access to operate, so it can be used anywhere. The so called Covid camera is designed to automate the process of measuring temperature and verifying that a person is wearing a mask. The resul...
Automatically analyzing financial data is the subject of much ongoing research. The purpose of this study was to research the possibility of using deep learning methods to predict and forecast the value of selected financial data in financial quarterly reports: cash flow from operating activities, cash flow from investing activities and cash flow f...
The goal of the article was the detection of anomalies and attacks in Software Defined Networks (SDN) with the appropriate selection and use of artificial intelligence algorithms and their parameters. The main challenge of the work was to determine which ensemble learning algorithm and with what parameters will allow the best detection of attacks a...
The article presents the concept of implementing a mobile system for determining the geographical location of the observed point using a network of unmanned flying objects tethered, called virtual masts. The presented concept was developed taking into account the possible loss of GPS signal and the related need to efficiently determine the geograph...
Photogrammetry allows a three-dimensional reconstruction of the object based on its multiple photographies. The quality of the reconstruction result depends mostly on the gloss, the diversity of the texture, the lighting conditions, the quality of the camera calibration and the shape of the object. The article presents the results of a simulation o...
The goal of the paper was to shorten the calculation time by realising all used signal processing algorithms in the form of stack filters. The architecture of these filters allows us to process signals using the advantages of hardware processing and simultaneous signal processing. This paper elaborated on the synthesis of stack filters which realis...
Video stream magnification allows people to see otherwise not visible subtle changes in surrounding world. In the article we present a method for GPU-based touchless object vibration measurement using IR video camera in order to process video stream in real time. We compare acquired results by the proposed method with the results from accelerometer...
The paper presents the use of the modified BLT method for the synthesis of the control system which task was to suppress disturbances. The controlled plant constituted a linearized multivariable model for the helicopter-type UAV. The first step of the modified BLT method is to tune PI controllers for each main channel. The article proposed the meth...
In the article a system for swarm management in the Prepar3D environment was presented. The system allow to simulate and control via graphical user interface swarm of UAVs. From the user’s perspective, the main advantages of such a system over a single machine would be: speed, no need to restock the UAV, elimination of the problem of transport spar...
This paper concentrate mainly on the indoor navigation aspects and secondly on inertial measurement unit (IMU) filtering. Presented reckoning navigation algorithms, are named odometry algorithms and are based on double acceleration integral algorithms. Acceleration before being integrated is multiplexed with orientation data that both are acquired...
The goal of the following paper was to devise a method of object tracking in a case when we have preliminary knowledge of an object. Tracking the object which state or some properties are known may be conducted with the pattern vector modification basing on this knowledge. The object which has the same visual images and different thermal images, de...
Training of officers, soldiers, guards and security personnel as representatives of the state security system responsible for ensuring public safety is a complex and multifaceted process, especially in terms of use of firearms. This process should be conducted at each level of tasks, which include the level of intervention, tactic and strategic whi...
The goal of the following paper was to devise a method of object tracking with the application of the tracked objects’ coloured images. The proposed solution was based on the calculation of an indicator which described the colour features of the object. The ratio between the red and green components as well as the ratio between red and blue compone...
In this chapter the concept of the system to locate objects in real time based on RFID tags was presented. RFID is a radio frequency identification technology (Radio Frequency IDentification). The technology is based on the use of radio waves of different frequencies to read coded information from the RFID tag to identify the object. The chapter pr...
During temperature tests of 18 acceleration sensors in 6 IMU modules, conducted in a climate chamber at a temperature range from −10 to +60 °C, temperature characteristics of zeros and gains of tested sensors were obtained. An algorithm is presented for compensation of the sensor readings using temperature characteristics. We also report results of...
Correct conducting of the geometric and photometric calibration of the image projection system provides the seamless and uniform visualization. In this publication an author’s method was introduced to the manual calibration enabling the calibration of the any number of DLP projectors, on-screen consisting of many planar surfaces. Based on tests the...
The aim of the article is to present augmented reality as an innovative technology used to create interactive applications. As part of the work there was created a computer game based on the three-dimensional image reconstruction technique. Achieving of the effect of augmented reality in application requires the use of techniques for mapping real o...
This book presents advanced technologies used in practice to enable early recognition and tracking of various threats to national security. It discusses practical applications, examples and recent challenges in the application fields using sophisticated sensory devices, embedded designs and airborne and ground unmanned vehicles. Undeniably rapid ad...
The article presents the development of innovative multimedia shooting detection system solving problems of existing solutions and characterized by four major advantages: algorithm of photometric recalibration, a gun bullet's hit detection video analysis algorithm using thermal imaging camera, IR laser spot tracking algorithm, implementation of bal...
The goal of the article is to present a novel Multimedia
Firearms Training System. The system was developed in order to
compensate for major problems of existing shooting training systems.
The designed and implemented solution can be characterized by five
major advantages: algorithm for automatic geometric calibration,
algorithm of photometric reca...
This paper presents the results of the study of influence of ambient temperature on the measurements of 3-axis linear acceleration sensors and gyroscopes used in IMU modules. The study was conducted using a climatic chamber, in which the six IMU modules were tested. Conducted tests covered a range of temperatures from −10 C to +60 C. The effect of...
The chapter presents a novel long-term object tracking method called SETh. It is an adaptive tracking by detection method which allows near real-time tracking within challenging sequences. The algorithm consists of three stages: detection, verification and learning. In order to measure the performance of the method a video data set consisting of mo...
The aim of the following study was to examine the influence of image thresholding on the correctness of the pattern recognition in the grey scale images. The method based on moment invariants, which were the elements of feature vectors defining the features of the recognised object, was used by authors in order to recognise the objects. The paper p...
The chapter presents a concept of utilization of active thermal camouflage combined with friend or foe recognition system. The main purpose of the system is automatization of decision-making, whether utilization of thermal camouflage is ought to be used. Moreover, the described system should react properly, when an enemy is detected. Implementation...
Anisotropic diffusion is well-known edge-preserving noise removing filter. Unfortunately, estimating parameters of this method can cause some problems. We aimed to find efficient solution to resolve this issue and decided to use GPU compute ability, because of that almost every operation is performed on GPU in parallel. It let us to estimate each p...
The aim of the following study was to examine the influence of image resolution in the pattern recognition in the grey scale images. In order to recognise the pattern, the authors used the method based on moment invariants which were the elements of feature vectors defining the features of the recognised object. The paper presents the influence of...
Video motion magnification (VMM) allows people see otherwise not visible subtle changes in surrounding world. VMM is also capable of hiding them with a modified version of the algorithm. It is possible to magnify motion related to breathing of patients in hospital to observe it or extinguish it and extract other information from stabilized image se...
Image enhancement is a challenging problem in the world of digital technology. Currently, producers of video cameras, are providing devices working with increasingly higher frequencies and resolutions of acquired video frames. However, that creates a need of development of methods used in image enhancement. Furthermore, real time processing of a si...
Video motion magnification (VMM) allows to amplify hardly visible changes in the video input sequence. It is possible to amplify breathing motion of hospital patients or oscillations of some mechanical element without need to connect measuring devices. On the other hand modified VMM algorithm can be used to extinguish motion before processing with...
The system which allows for visualisation of range of motion examination has been developed. The visualisation is clear and in simple manner presents measured angles in the joints. Measurement is based on data from motion capture system about location of the markers on the patient. Markers are place at key locations in this way that connection of n...
OVAD (Fraś et al. in Vision based systems for UAV applications, Springer International Publishing, pp. 123–136 [1]; Kwiatkowski et al. in Recent advances in electrical engineering and computer science, pp. 58–61 [2]) is a device, which is purposed for multi directional video acquisition. Further development of the device includes hardware implement...
We present the example of Attitude Indicator Augmented Reality (AR) control for the unmanned aerial vehicles (UAV) ground control station. The article describes perspective heads-up display overlaid on the image, which is acquired from the UAV rotatable camera. Article shows the mechanisms of aircraft camera calibration with the AR artificial horiz...
The goal of the following paper was the synthesis of multivariable control systems. Due to the popularity and usability of the BLT method for tuning such systems, we proposed a certain modification. The BLT method uses the Ziegler-Nichols (ZN) method for tuning the PI regulators for the main channels. The limitations caused by the ZN method for the...
The following paper presents of the use of the modified BLT method for the synthesis of the control system of the UAV. The small helicopter was the example of the UAV. This method was used for controlling the linear acceleration in the vertical axis and angular velocities around the UAV’s symmetry axes. The linearized multivariable model was used a...
Laser Point Tracking (LPT) is algorithm dedicated to rapidly moving laser-generated blob. By usage of few features: brightness, area and velocity, it is able track blurred and dark trail of laser. Further research were made to overcome problems, which occur while tracking two lasers simultaneously. The acquired results are promising. The presented...
The goal of the following paper was to develop the methodology of recognising a given object out of other objects in the grey scale images. We have presented the method which utilises moment invariants for creating model vectors which define the features of the recognised object. Moreover, we have discussed the rules of creating the model vectors w...
The aim of the following study was to develop a procedure which guarantees the separation between the part of an image where we have the recognised object and the part of the image which corresponds to the terrain where the object moves. This research is conducted for grey scale images. The authors have presented the method which uses moment invari...
This monograph provides comprehensive guidelines on the current and future trends of innovative simulation systems. In particular, their important components, such as augmented reality and unmanned vehicles are presented. The book consists of three parts. Each part presents good practices, new methods, concepts of systems and new algorithms. Presen...
We present the concept and implementation of unobtrusive wearable network of sensors and distributed control system for integrated monitoring - acquisition, processing, analysis of human motion and other physiological modalities. The entire system, hardware and software are scalable and compliant with the Wireless Body Area Network model. The weara...
The article presents a novel long-term object tracking method called SETh. It is an adaptive tracking by detection method which allows near real-time tracking within challenging sequences. The algorithm consists of three stages: detection, verification and learning. In order to measure the performance of the method a video data set consisting of mo...
Range of motion measurements are used by physicians, physical therapists and veterinarians. There is a need for a solution that would increase the accuracy and repeatability of the measurements obtained. Commonly used methods are based on tests using a classical goniometer are often inaccurate and depend on the individual interpretation of result b...
Laser Point Tracking is algorithm dedicated to rapidly moving lasergenerated blob. Even if common tracking problems like occlusion, intense background noises or illumination changes do not exist there we found it challenging to track that simple shape. Proposed method, by usage of few features: brightness, area and velocity, is able to overcome sev...
The paper presents design of Remotely Operated Vehicle - ROV prototype.
To date, the operator has the ability to seamlessly move and maneuver both
horizontal (geographic change in direction, moving from point to point) and vertical
(change of depth of submerged position). Solid construction provides resistance
to mechanical damage, and the ergonomi...
The paper presents the modules of the control system remotely operated
unmanned underwater vehicle used to stabilize the exchange rate and maintain the
direction of motion. The authors present a simple control algorithms, and presented
the verification of the assumed conditions of a real object. The control algorithms
used information from the acce...
The first idea to replace the human factor in danger zone with unmanned robotized vehicles that was defined and implemented at Military University of Technology has been presented in this article. The concept of implementation of components of the remote control system to transform the main battle tank T-72 into Unmanned Ground Vehicle to perform m...
The article presents a method for camera calibration for tracked vehicles augmented reality applications. The method does not require any additional optical markers or symbols placed within the observed scene. The approach can be used regardless the quality of placement of optical markers, which could be disturbed due to object’s damage or contamin...
The article presents the potential use of computer systems for remote evaluation of soldiers’ vital signs and the transfer of results to the Command and Control Center or the Medical Support Centre. This article also suggests a number of possible solutions that can be successfully adopted both in training and in combat conditions. Furthermore, it i...
The following paper examined the significance of the velocity limitations in the camera head control system. A prerequisite for the control system was that it should quarntee the tracking of an object moving on the ground, even in the case of disturbances such as the rapid rotations and shifts of the UAV. Equipping the UAV with the flight trajector...
The goal of the paper was to examine the changeable gain in the camera head control system which is applied to object tracking. The study assumed that in order to track objects moving on the ground, the UAV with the mounted camera would be used herein. During the flight of the UAV, there may appear various disturbances such as rapid rotations and s...
The purpose of this article is to present the designed and implemented Mobile Ground Base Station for UGVs. It was designed by the team from Silesian University. The MGBS (Mobile Ground Base Station) was tested using two different types of loopbacks: SIL (Software In the Loop) and HIL (Hardware In the Loop). After performing tests in virtual realit...
The problem of impact resistance the vehicles is described in various articles and standardization documents. Mainly concerns on small size of explosive device. In the case of large charges like a 25 to 1000 kg, the literature of subject is very poor. Practically, when the mass of charge is over 1000 kg the level of security of vehicle do not have...
In this paper the Master Control System is presented, which allows remote manual control of a number of robots by means of chosen input devices. Main focus is placed on the problem of user friendly control, reducing operator workload and computer controlled intervention increasing safety of subject vehicle.
The purpose of this article is to present the influence of the environment on the propagation of shock wave and the dynamic response of the plate and the special vehicle load by shock wave. In the course of research in this field experimental study was performed. Experimental study concerns the test plate load by shock wave, formed after the detona...
The paper presents an approach to modelling of explosion on a vehicle. The studies take into account the impact of the secondary wave on a crew inside the vehicle. It is known that the impact of explosion on the crust (hull) of a vehicle creates a secondary wave phenomenon. The phenomenon rests on the interaction of the bottom and sides of the vehi...
This book has been motivated by an urgent need for designing and implementation of innovative control algorithms and systems for tracked vehicles. Nowadays the unmanned vehicles are becoming more and more common. Therefore there is a need for innovative mechanical constructions capable of adapting to various applications regardless the ground, air...
In this paper we propose the upper, and in some cases, lower bounds for norm of solution of linear discrete time-varying system by coefficients matrices. We show that our estimates have two merits. Firstly, we do not need to know eigenvalues or spectral norm of matrices because we can simply calculate it by matrix
coefficients. Secondly, our bounds...
The purpose of this paper is to present some results on the effects of parametric perturbations on the Lyapunov exponents of discrete time-varying linear systems. We fix our attention on the greatest and smallest exponents.
In this note we describe the maximal and the minimal values of Lyapunov exponents for second-order discrete time-invariant linear system perturbed by time-varying bounded perturbations. An interpretation of the results in terms of generalized spectral radius is given. An application of obtained formulas to the robust stability problem is demonstrat...
In this paper we present a sufficient condition for continuity, called in the paper stability, of Lyapunov exponents of discrete time-varying linear system. Basing on the result we show that Lyapunov exponents of time-invariant systems depend continuously on the time-varying perturbations.
Measuring the orientation of the mobile objects is essential for autonomous navigation. In order to construct low cost, miniature aerial vehicles a miniature inertial measurement unit was designed and constructed by the research team from Silesian University of Technology. Presented device can be distinguished by many times smaller volume than the...
In the article a group of vi libraries ("virtual instrument") of the simulation - programming LabVIEW environment, enabling the construction of a program that would be the basics of the image programming and analysis system, are presented. Presented libraries are dedicated for the Vivotek, supporting the SDK module ("VitaminCtrl"). They provide the...
In this chapter we present simulation results of an algorithm designed to planning collision free path based on probabilistic search. The aim of this study is to design an algorithm for off-line planning a set of way-points which make the collision free route of an Unmanned Aerial Vehicle (UAV). The planning process is based on the graph that repre...
This article presents design and implementation of a gyro-stabilized platform for visible light and infrared image acquisition. The process of selection of appropriate vision sensors and their calibration is presented. Additionally there are presented results of conceptual work, design and construction of the working prototype of the device.
The aim of this methodology is a creation of a tool which would be able to construct a system for obtaining information about objects in the environment of the vision system. This task is often defined as a sub-task in the primary problem of the automatic task completion by the independent UAV unit using visual information. These researches concern...
This article describes communication system designed and implemented on Silesian University of Technology based on experience acquired in previews projects. Communication system was designed for micro UAVs. First part of this work describes physical layer and second part describes software layer such as data encryption, establishing and maintaining...
This paper presents a novel approach to the problem of managing mobile robots. It is presupposing the existence of the virtual space in which the calculations are made and the real space containing registered mobile robots. Developed and implemented system combines the best features of agent systems and mobile robot management systems based on a ce...
The main goal of this paper is to implement and test various target detection algorithms in thermal imagery. The topic of target detection and moving target detection in infrared video streams is considered as a very challenging research topic in computer vision discipline. Although there is a huge number of different algorithms developed for targe...
Night time surveillance is an important task for existing monitoring solutions. There is a need for low cost and high light-insensitivity solution. In this paper we present a results acquired during night indoor surveillance using three common vision devices and RGB-D camera. Experiments were performed in full light, minimal light and pulsating lig...
Unmanned aerial vehicles (UAV) are very useful platforms for detecting and tracking objects which are located on the ground. The crux of the considered problem is the tracked object which disappears from a field of view. The above mentioned may be caused by rapid camera movements. One of the examples of such a situation is the camera being attached...
The solution of the camera head control problem was presented in the paper. The main goal of developed control algorithm is the object tracking in rapid disturbance conditions. The changes of the helicopter position and orientation during the time of disturbance result in losing tracked object from the field of view. Due to this fact the helicopter...
The article presents designed and implemented system for multi-axial mechanical stabilization. The quality of stabilization using closed-loop control, open-loop control and open-loop control with prediction was experimentally measured. Acquired results are presented and discussed
This article concerns prototyping of the control algorithms for unmanned flying objects using the virtual reality. More specifically, there is discussed an integration between simulation environment and unmanned aerial vehicle (UAV) control software. This integration is based on software in the loop simulation. The control software uses PI controll...
This paper presents a designed and created prototype of stabilized UAV gimbal for day-night surveillance. There is a need for UAV gimbals capable of stable target detection and tracking, regardless the time of the day. The prototype gimbal is capable of pan and tilt rotations in range of full 360 degrees with 10 bit turning resolution. Full turn ta...
This article provides information on smart grid and smart measurement systems with a special focus on the advantages of their implementation as well as concerns present at the stage of design and component selection. The tests conducted on a selected group of measurement devices used in smart grid systems made it possible to compare power losses ch...
Omnidirectional video acquisition device (OVAD) is an innovative concept that may find many applications both civilian and military. It can be used to observe areas that may need wide area monitoring such as shops, banks, petrol stations. In military installations OVAD may be used to patrol the area from the ground or from the air. Application allo...
This paper presents how the Virtual Reality (VR) technology and Computer Graphics (CG) is used nowadays by industry to reduce productions costs, minimize learning curve and eliminates hazard situations. Few examples of procedural training and VR simulators are being presented, as well as the usage of CG for military training and troops support.
In this article is described used in Research and Development Center of Mechanical Appliances OBRUM sp. z o.o. method of vehicle R&D cycle support using serious gaming (SG) solution. Implemented in OBRUM sp. z o.o. solution is described on example of Multipurpose Engineering Machine (WMI) with remote control functionality requirement. Short serious...
In the paper a method for fast IMU calibration is described. The method need previously calibrated IMU, called standard IMU. Standard IMU and IMU to be calibrated have to have a solid mechanical connection. Then a sequention of movement is done and an outputs from both IMUs are recorded simultaneously. Outputs can be recorded with different samplin...
One of the world’s leading problems in the field of national security is protection of borders and borderlands. This book addresses multiple issues on advanced innovative methods of multi-level control of both ground (UGVs) and aerial drones (UAVs). Those objects combined with innovative algorithms become autonomous objects capable of patrolling ch...
This monograph is motivated by a significant number of vision based algorithms for Unmanned Aerial Vehicles (UAV) that were developed during research and development projects. Vision information is utilized in various applications like visual surveillance, aim systems, recognition systems, collision-avoidance systems and navigation. This book prese...
This paper presents Embedded Inertial Navigation System designed and manufactured by the Department of Automatic Control and Robotics in Silesian University of Technology, Gliwice, Poland. Designed system is currently one of the smallest in the world. Within it there is implemented INS-GPS loosely coupled data fusion algorithm and point-to-point na...
Concealed weapon detection (CWD) is an important part of everyday law enforcement. There are numerous facilities that are endangered of an terrorist or an fanatic individual attack. Commercially used weapon detection gates are very expensive and sometimes impossible to install into already existing security infrastructures. Here we present a miniat...
We present the prototype of unmanned aerial vehicle (UAV) as a platform for multispectral acquisition. We are connecting the real-world simulation environment and control software to perform flight tests in SIL simulation. The full control system is based on the cascade of PI controllers with Anti-Windup mechanism, which stabilize the aircraft in t...
This note studies the problem of bounds for the Lyapunov exponent of a parameter perturbed system when the perturbation has finite average value. Such a bound is presented in terms of Bohl exponent of the unperturbed system. In particular, it has been shown that the Lyapunov exponent of perturbed system is not greater than the Bohl exponent of the...
The paper explores possibilities of applying the IR thermography for integrity evaluation and quick detection of failures in natural gas delivery stations. The natural gas stations typically comprise overground facilities for filtering, pressure reduction, flow metering and odorizing. The facilities and the interconnecting pipelines are subject to...
In this paper we discuss different types of controllability of jump linear systems. We start with the weakest of the concepts of controllability for jump linear system namely the problem of controllability of the expectation of the final state. The main result of this section gives a necessary and sufficient condition for this type of controllabili...
In the article aspects of classified information protection in data bases and IT&T systems were presented. Attention was drawn to formal and legal requirements which in an obligatory manner must be fulfilled by such systems. In the article the issue is discussed of the necessity to obtain system accreditation by the Agency for Internal Security (AB...
Security of endangered strategic areas like gas delivery stations is at the moment almost completely dependent on security officers and visual inspection of the scene. Observation of multiple screens displaying images captured from video cameras installed at the station is a monotonous task, therefore there is a great risk of occurring oversights....
In this paper we describe the maximal and the minimal values of Lyapunov exponents for second order discrete time invariant linear system perturbed by time varying bounded perturbation. The results may be interpreted in terms of generalized spectral radius and applied to obtained formulas for robust stability problem.