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This paper deals with the calculation of 3D flow in a gas turbine and a nozzle with variable geometry of small jet engine ISTC-21V placed in a laboratory LIRSLM at Faculty of Aeronautics. It was used methods of meshing around the geometry of the CAD model and the CFD calculations for viscous flow. The resulting data was then compared to the measured in the laboratory and calculated from the analytical model of the engine. The evaluation has proved the credibility of the calculation to be used as additional knowledge of engine parameters.

The paper deals with approaches in controlling of a complex electro-mechanical system. The proposed system is servomotor as a part of camera gimbal intended for UAVs (Unamnned Aerial Vehicles). Camera gimbal is a non-linear system with hysteresis and transport delays. The paper deals with experimental data driven method of servomotor modeling and also with classical control algorithms method and control algorithms based on fuzzy logic. The presented methods, approaches and applications are directly usable for similar electro-mechanical systems. The presented solution is cost effective, precise and fast using advanced algorithms.

The article presents a method for implementation of "anytime" algorithms into digital real-time control system for a small turbojet engine iSTC-21v. This method presents an approach that will be used for future work in design of the control system. The presented method is an extension of the actual developed control system of engine, which uses the theory of situational control of complex systems. This control system uses progressive control algorithms. For practical implementation of this control system it is important to think about computational complexity. Control systems of aircraft engines use computer (Full Authority Electronic engine control — FADEC) with limited computation resources. Aircraft engines work in environment with stochastic conditions. It is necessary to ensure reliable and stable operation of engine. Anytime algorithms can help to solve this problem and to meet the safety requirements.

How to use an old turbo-compressor (turboshaft) engine and transfer it into a laboratory system used for design and development of progressive control, diagnostic and modeling algorithms transforming it into an intelligent turbo-compressor engine? The intelligent turbo-compressor engine currently designated as iSTC-21v is a small turbojet engine with a single sided radial compressor, bound combustion chamber, single stage un-cooled turbine and variable exhaust nozzle. The engine is equipped with a real-time measurement and intelligent digital control system using two degrees of freedom (fuel supply and exhaust nozzle diameter). The article describes transformation of an old TS-20/21 engine into such engine, which is suitable for laboratory use, research in different areas of cybernetics with perspective applications in different areas of technical practice like unmanned aerial vehicles, ground auxiliary energetic units, generators, etc. The article is aimed to be inspirative also for hobby engine builders, scale modelers and people who work with small turbo-compressor engines.

The goal of this article is to develop a linear mathematical model for a small scale turbojet engine with variable convergent nozzle, and validate it on existing laboratory hardware owned by the authors’ Departments.Control of gas turbine engines plays an essential role in the safety of aviation. Although its role is constantly expanding, ranging from pilot workload reduction to detailed diagnostics, the basic competence is to regulate the thrust output of the power plant with maximum available accuracy, rapidity, stability, and robustness. The linear quadratic control is one possible solution for the above mentioned criteria.Although civil aircraft engines include fixed exhaust nozzle geometry, in military applications the exhaust nozzle geometry is also adjustable to reach optimum efficiency due to better matching of individual engine components, etc.In the present article the authors deduce the members of state space governing equations to acquire the basis of the LQ control.The established model is based on the physical laws describing the operational behavior of the engine as well as its complexity should be reduced to an acceptable level where still enough details remain to reflect the nature of the controlled object.

This contribution presents a proposal and practical implementation of a digitally controlled fuel system for control of fuel supply into a small turbojet engine, iSTJ-21V. In the past, for the purposes of fuel metering to the engine MPM-20, which was a previous version of the iSTJ-21V, the servo valve LUN 6743 was used. However, this solution has several disadvantages such as increased strain on the fuel pump and non-linear characteristics. The new fuel control system was tested on a measuring stand and implemented into microcontroller platform and tuned during full operation of the engine. As microcontroller platform the 32 bit NXP LPC1768 microcontroller was chosen. The contribution consists of the principle of control of a small turbojet iSTJ-21V engine and a summary of the results in a graphical form. The main contribution of this work is to create a digitally controlled fuel system with sufficient accuracy control of fuel supply to the engine the need to increase its effectiveness and application of modern control algorithms at a higher level.

Content of this contribution is proposal of Inertial Measurement Unit (IMU) for unmanned aerial vehicle. Verification of the real proposal is based on the creation of the integration algorithm utilizing magnetometer data, which outputs are values of speed, distance and attitude angles. Sensor units for proposed measurement unit are chosen considering the criteria, which are described. For this proposal and measurement is used accelerometer ADXL335, gyroscope L3G462A and magnetometer HMC5983. The contribution consist the overview of the chosen mathematical approaches and summary of the results in graphical form. The verification of proposed algorithm is in range of this contribution made on the proposed IMU unit on board of the unmanned aerial vehicle (UAV).

Increased redundancy of systems has always been one of the key points to increase reliability and safety of operation of aircraft engines. A special class of such engines is represented by small turbo-compressor engines suitable for propulsion of small aircraft or ground and laboratory use. Specifics of such engines demand design of specialized approaches in order to increase redundancy of their sensor/control systems, thus increasing their operational reliability and safety. The paper proposes general architectures for cost effective approaches to increase the redundancy of sensor and control systems by application of virtual sensor channels and intelligent selectors. The virtual channels are represented by neural networks fusing data from other sensors to dynamically compute the backed up parameter. Intelligent selectors form decision making elements that select the correctly operating control channel. The integration of these two elements creates an intelligent highly redundant sensor and control system suitable for small turbo-compressor engines.

This paper provides a description of a hybrid method for automated evaluation of qualitative parameters. The method is presented on an example of efficiency evaluation by planning experiments with specified set of key performance indicators in case of a turbojet engine in laboratory of intelligent control systems of jet engines (LIRS LM). The implementation of this example is done in form of a state of the art information system concept, created particularly for managing research related data, information and knowledge in from a single research field. The paper also denotes further possibilities in creating prediction models for qualitative parameters that may be used in intelligent data-driven or quality-driven control of the respective system. Other possibility is to expand the key concept of the information system, and utilize the knowledge gained from the results in training of operators and experimenting personnel.

Small turbo-compressor engines represent a specific class of such engines with application in small aircraft and as auxiliary energetic units. Energetic efficiency and high safety standards are nowadays key factors in practical applications of small turbo-compressor engines. One approach to achieve these aims is to design and utilize progressive control algorithms. As turbo-compressor engines represent a non-linear systems operating in a broad range of environments and inner conditions, taking the adaptive approach in controller design can be beneficial. The presented article tests and evaluates different basic approaches in adaptive controller design for a small turbo-compressor engine with modeled altitude and speed characteristics.

In order to achieve higher efficiency and to explore new progressive approaches in control of turbo-jet engines with more than one degree of freedom, the experimental turbojet engine MPM-20 has to be expanded with flexible geometry exhaust nozzle. The article is aimed at design of a mechanism, which would control the variable geometry exhaust nozzle of the engine allowing its practical application. Selection and precise analysis of the appropriate actuator for the needs of digital control of exhaust nozzle and design of the appropriate modifications for its practical use in laboratory conditions are presented. The presented design is usable for similar class of such engines in laboratory conditions.

Progressive development of turbojet engine requires focus not only on improving performance, but also high reliability and safety are very important. That's why we put more and more emphasis on concepts like diagnostics and backup, which represent the basic techniques and methods that contribute to increased safety of any complex system. The article deals with the design of diagnostics/backup system, which uses majority method and backup through computational models that take advantage of experimental identification methods and neural networks. The proposed system for jet engines was subsequently tested in laboratory conditions (LIRS LM-Laboratory of Intelligent Control Systems of Jet Engines) on a small turbojet engine MPM-20, where confirmed its functionality and reliability.

The presented paper proposes a design of a scientific research information system (SRIS), intended for real world use according to existing requirements and processes in the Laboratory of Intelligent Control Systems of Aircraft Engines. The novelty of the proposed SRIS lies in universal and narrow scope of the system and digitalization of existing manual processes, with the addition of algorithms and methods for research efficiency evaluation. The key idea is the possibility to design own quantitative key performance indicators (KPIs) for the efficiency evaluation. It is possible to generalize the presented approach for any research environment, either for technical, financial, time related or information efficiency evaluation. In case of a complex technical systems, the SRIS can also be considered a decision support system (DSS), when using various data mining algorithms e.g. clustering, classification, association rules, etc.

The article is focused on diagnostics in the field of aviation turbo-jet engines. Evaluation of their technical status, and potential failures and pre-failure processes can be improved by monitoring their thermally loaded components. Part of the research in the given area also involves mathematical modeling of the channel measuring the exhaust gases temperature, using neural networks to compensate for dynamic errors of slow thermocouples used in such measurements.

Controlling position of an aircraft in its trajectory is a matter of high precision. The requirement on precision is becoming a priority primarily in the phase of landing, when the aircraft is in automated mode of landing controlling/maintaining lateral deviation along the trajectory by autopilot. The contribution is describing shaping and modeling control signals in the stage of final approach for landing. It proposes a system that can eliminate the interfering high-frequency defects of lateral control system stabilizing aircraft deviation during the landing maneuver and simulating the effects of filters onto the feedback dynamics.

The paper deals with design of an intelligent supervisory system usable in the area of engineering applications of small turbojet engines. Such supervisory system consists of diagnostic and control system applied in different phases of the engine’s operation. In order to design it we need to know the object and its models that will be realized by means of situational modeling concept and neural networks. Diagnostic system will be based on these types of models applied into the majority voting method of online diagnostic. Intelligent supervisory system will also include off-line pre-start diagnostics for such engine with perspective health monitor database.

This paper presents a general description of behavior of a complex thermodynamic system, represented by a small turbojet engine MPM 20. The main aim is to provide basic constraints of chosen measured parameters. Obtained results will be used in future data filtering, to recognize faulty output sensor values, critical situations and normal engine operation field. According to these constraints the engines' operational envelope can also be defined by means of measured parameters. Also using constraints, we may divide the engine operation into several operational modes. These modes are dependent on the absolute value of a measured parameter, a coefficient of two parameters, or a coefficient calculated by more than two parameters.

Summary form only given. The Laboratory of Intelligent Control Systems of Aircraft Engines has been built around the idea of design implementation and testing of progressive algorithms in the areas of identification, modeling, control and diagnostics of complex systems. As such complex system a class of small turbojet engines suitable for laboratory experiments and utilization has been used, the engine MPM-20 derived from turbo-starter TS-20 in particular. Such small turbojet engines exhibit similar dynamic behavior as normal sized engines and have many properties of complex systems like non-linear characteristics, variable cross bindings, broad operational range, non stationary parameters and elements of stochastic behavior.

Development of aircraft engines is aimed on increase of reliability, efficiency and ecology of operation. The presently still used hydro-mechanic control systems are being replaced by electronic ones characterized by high speed, precision of control and ability to optimize all operating regimes of an engine. One of the aims of research in the Laboratory of intelligent control systems of aircraft engines lies in new possibilities of expansion of working envelope of turbojet engines by implementation of variable exhaust geometry and new approaches in its control strategies and construction solutions. Such expansion can be beneficial for small turbojet engines and increase their possibilities of real-world applications. New control methodologies and approaches can be further expanded to normal sized engines. All these problems are described in the presented article.

The article deals with basic description of turboprop engines as a special class of turbine engines - advanced approaches in its modeling and control. The article will deal with description of analytical and experimental approaches in modeling of individual parts of the engine with description of their thermo-dynamics and states. Such engines are systems with two degrees of freedom and demand advanced control algorithm in case of control with single control lever. The article will deal with design of such control algorithm with perspective use of advanced control methods. Such approaches will increase efficiency, fuel consumption, safety and control comfort for the pilot.

The main thesis of this paper considers the possibilities and difficulties of switching from hydromechanical engine control to FADEC (digital) engine control. Regarding different specifications and elements in system, possible errors, advantages and disadvantages, each method has its specific properties of behavior in specific environments and applications. When considering our controlled system, the MPM-20 small turbojet engine, it is a challenge to propose functional control system with backups and with slight possibility of errors during or before operation. In this paper we propose methods of backups for specific elements, prestart diagnostics and on-line diagnostics.

This paper deals with modeling and diagnostics of complex systems and with a prestart diagnostics expert system design and implementation. In the area of modeling, the authors describe dynamic models of the speed dependence upon the fuel flow supply of a small turbojet engine MPM-20. The first model is done with use of neural networks and the second is a linear model. Both models are then methodologically incorporated into the diagnostic and backup system of the optical sensor measuring the engine speed.

The paper deals with approaches in modeling of a complex electro-hydro-mechanical system. The proposed system is a fuel metering device that is a non-linear system with hysteresis and transport delays. The classical methods of modeling demand knowledge of mechanics and inner structure of the researched object. The paper deals mainly with experimental data driven methods of modeling. The created models will serve as a basis for controller design to employ the fuel metering device into the digital control system of a small turbojet engine MPM-20.

The article is focused on diagnostics in the field of aviation turbo-jet engines. Evaluation of their technical status, and potential failures and pre-failure processes can be improved by monitoring their thermally loaded components. Part of the research in the given area also involves mathematical modeling of the channel measuring the exhaust gases temperature, using neural networks to compensate for dynamic errors of slow thermocouples used in such measurements.

The paper deals with modeling and diagnostics of complex systems. In the area of modeling, the authors describe dynamic models of dependence of speed upon fuel flow supply of a small turbojet engine MPM-20. The first model is done with use of neural networks and the second is a linear model. Both models are then methodologically incorporated into the diagnostic and backup system of the optical sensor measuring the speed of the engine.

Mathematical modeling represents an efficient method allowing us to examine properties of a researched object [1]. Realization of mathematic models has become a fundamental part of design of many complex systems. By use of simulation, we can experiment with mathematical model similarly as with the real object without the risk of damage and with much lower expenses. Modeling represents experimental process that asserts the examined original (the modeled system) unambiguously another physical or abstract system. The article deals with approach to virtual particular analytic modeling of a compressor and explores some advanced hybrid concepts in modeling of such engine using methods of artificial intelligence.

This article is concentrated on research of magnetic aura of aircraft engine MPM 20 during its operating modes. Next aim of this article is description of usability of magnetic aura for MPM 20 situational control by fuzzy controller.

Mathematical modeling represents an efficient method allowing us to examine properties of a researched object [1]. This article will present the design of an analytic model of a jet engine (MPM-20 engine in particular) that will be used to set the operational envelope of the engine for further use in a control system that will be limited by this envelope.

Mathematical modeling represents an efficient method allowing us to examine properties of a researched object [1]. Realization of mathematic models has become a fundamental part of design of many complex systems. By use of simulation, we can experiment with mathematical model similarly as with the real object without the risk of critical states and with much lower expenses. Modeling represents experimental process that asserts to the examined original, the real object (or the modeled system) unambiguously another physical or abstract system. The article deals with approach to virtual modeling of a compressor in a small turbojet engine. This article will present design of analytic model of a jet engine (MPM-20 engine in particular) and its graphical depiction into its compressor characteristics.

The article deals with modern concepts of control systems used in turbojet engines. We specifically aim on description of control systems using methods and concepts of artificial intelligence, which can bring a new quality in terms of operation and safety of turbojet engines' operation. We also propose a design of intelligent control system for small turbojet engine MPM-20 within the scope of methodology of situational control together with exploration of macro and micro situations concepts.

The growing demands on safety authority and intelligence of control systems requires new approaches in design. One approach that is usable and potentially effective are anytime control algorithms that can be used in the area of modeling and control [6, 11, 14, 15]. Use of such algorithms allows the system to flexibly react on changes of outer environment and be able to survive deficiency of time, information and resources.

Mathematical modeling represents and efficient method allowing us to examine properties of a researched object [1]. Realization of mathematic models has become fundamental part of design of many complex systems. By use of simulation, we can experiment with mathematical model similarly as with the real object without the risk of critical states and with much lower expenses. Modeling represents experimental process that asserts to the examined original, the real object (or the modeled system) unambiguously another physical or abstract system. The article deals with approach to virtual modeling of a compressor in a small turbojet engine.

The article deals with full authority digital engine control (FADEC) systems and possibilities of application of concepts and methods of artificial intelligence in such control system. FADEC represents a framework where the most modern methods of artificial intelligence can be applied. This represents a great potential for increase of reliability, efficiency and overall quality of control of turbojet engines. We are trying to design and implement a FADEC control system for our small experimental turbojet engine MPM 20.

The article deals with basics of modeling of our small experimental turbojet engine MPM 20 and the following design of a complex situational control system with elements of anytime control algorithms bound with a developed analytical model of the engine. By use of advanced algorithms using methods of artificial intelligence in a robust framework to achieve the aims of reliability and high efficiency, we are trying demonstrate their usability and proficiency in the area of turbojet engines. All the tests and data come from measurements on a real object of our experimental small turbojet engine and are therefore a good step to be used on normal sized engines.

Small turbojet engines represent a special class of turbine driven engines. They are suitable for scientific purposes and research of certain thermodynamic processes ongoing in turbojet engines. Moreover such engines can be used for research in the area of alternative fuels and new methods of digital control and measurement. Our research, which is also presented in this article, is headed toward these aims. We evaluate and propose a system of digital measurement of a particular small turbojet engine - MPM 20. Such engine can be considered as highly non-linear large scale system. According to obtained data and experiments we propose different models of the engine and design of situational control algorithms for the engine with use of certain methods of artificial intelligence as new methods of control and modeling of large scale systems.

Small turbojet engines represent a special class of turbine driven engines. They are suitable for scientific purposes and research of certain thermodynamic processes ongoing in turbojet engines. Moreover such engines can be used for research in the area of alternative fuels and new methods of digital control and measurement. Our research, which is also presented in this article, is headed toward these aims. We evaluate and propose a system of digital measurement of a particular small turbojet engine - MPM 20. Such engine can be considered as highly non-linear large scale system. According to obtained data and experiments we propose different model models of the engine and design of situational control algorithms for the engine with use of certain methods of artificial intelligence as new methods of control and modeling of large scale systems.

Small turbojet engines represent a special class of turbine driven engines. They are suitable for scientific purposes and research of certain thermodynamic processes ongoing in turbojet engines. Moreover such engines can be used for research in the area of alternative fuels and new methods of digital control and measurement. Our research, which is also presented in this article, is headed toward these aims. We evaluate and propose a system of digital measurement of a particular small turbojet engine - MPM 20. Such engine can be considered as highly non-linear large scale system. According to obtained data and experiments we propose different approaches to modeling of the engine with use of analytic experimental and certain methods of artificial intelligence as new methods of modeling of large scale systems.

Small turbojet engines represent a special class of turbine driven engines. They are suitable for scientific purposes and research of certain thermodynamic processes ongoing in turbojet engines. Moreover such engines can be used for research in the area of alternative fuels and new methods of digital control and measurement. Our research, which is also presented in this article, is headed toward these aims. We evaluate and propose a system of digital measurement of a particular small turbojet engine -MPM 20. Such engine can be considered as highly non-linear large scale system. According to obtained data and experiments we propose different model models of the engine and design of situational control algorithms for the engine with use of certain methods of artificial intelligence as new methods of control and modeling of large scale systems.

Aircrafts' turbo-compressor engines may be considered as very complex systems with many mutual and also positive feedbacks. Another characteristic of such systems is that they operate in a very large range of outer environment parameters which causes very different behaviour within their working conditions. Critical susceptibility to erroneous states where requirements for reliability are set to highest degree, it is necessary to secure control of such engines in their every state and secure their operation under every environmental or engine conditions. Situational control methods offer such tools to secure not just stabilization of an engine, but its control, using different control strategies for different working conditions.

Small turbojet engines represent a special class of turbine driven engines. They are suitable for scientific purposes and research of certain thermodynamic processes ongoing in turbojet engines. Moreover such engines can be used for research in the area of alternative fuels and new methods of digital control and measurement. Our research, which is also presented in this article, is headed toward these aims. We evaluate and propose a system of digital measurement of a particular small turbojet engine - MPM 20. Such engine can be considered as highly non-linear large scale system. According to obtained data and experiments we propose situational model and situational control algorithms for the engine with use of certain methods of artificial intelligence as new methods of control of large scale systems.

A previous study of visual and auditory hemispheric cuing in horizontal sound localization found modality‐dependent effects of cuing resulting in biases in responses [Kopco, Tomoriova, Andoga, J. Acoust. Soc. Am. 121, 3094, 2007]. The previous study also suggested that some of the effects might be due to eye movements as eye fixation was not controlled. The goal of the current study was to isolate the attentional effects from the eye movement effects. An experiment identical to the previous one was performed, with the exception that the subjects were fixating the center of the audiovisual display. Localization performance was measured for transient auditory stimuli originating in the frontal horizontal plane. In most runs, a cue preceded the stimulus and indicated (correctly or incorrectly) the hemisphere (left vs. right) from which the subsequent target arrived. The cues differed by modality and the cue‐to‐target onset asynchrony. The listeners were instructed to focus their attention to the cued side. C...

Experiments were performed to determine 1) whether a priori information influences sound localization, and 2) whether the influence depends on the modality through which the information is provided. Localization performance was measured for transient auditory stimuli originating in the frontal horizontal plane. In most runs, a cue preceded the stimulus and indicated (correctly or incorrectly) the hemisphere (left vs. right) from which the subsequent target arrived. The cues differed by modality and the cue‐to‐target onset asynchrony (SOA: 400 to 1600 ms). The listeners were instructed to focus their attention to the cued side. A follow‐up experiment evaluated the effect of eye fixation on the visual‐cue performance. Results show modality‐dependent effects of cuing in terms of both bias and standard deviation in responses. A cue that indicated an incorrect side biased the responses towards its side in both modalities, while a visual correct‐side cue caused either no bias or a lateral bias. A visual cue tha...