Lidé

doc. Ing. Pavel Pačes, Ph.D.

Všechny publikace

Artificially Intelligent Assistance for Pilot Performance Assessment

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Insaurralde, C.
  • Publikace: 2021 IEEE/AIAA 40th Digital Avionics Systems Conference (DASC). Piscataway: Institute of Electrical and Electronics Engineers, 2021. p. 1-6. 1. vol. 1. ISBN 978-1-6654-3420-1.
  • Rok: 2021
  • DOI: 10.1109/DASC52595.2021.9594487
  • Odkaz: https://doi.org/10.1109/DASC52595.2021.9594487
  • Pracoviště: Centrum umělé inteligence
  • Anotace:
    Current teaching and evaluation practice for flight training lessons are carried out by humans. The instructor is responsible for evaluation of the student pilot skills. Pilot performance is typically assessed by the comparison of printed flight profiles with expected trajectories. This manual process means a significant workload for instructors who must deal with several evaluations of pilots’ critical tasks. Artificial Intelligence (AI) is an attractive ad hoc solution for highly skilled and sophisticated activities traditionally performed by human beings. This paper presents an approach to assess airplane’s pilot performance based on AI algorithms. This paper describes a setup to provide a capability for data collection from a certified flight simulator and employ the above algorithms capable of evaluating airplane’s pilots’ behavior as well as pilot’s progress during a training. Initial simulation results are encouraging as to produce satisfactory comparisons of pilots’ performance and suggest a potential AI-assisted support for pilot performance assessment. Concluding remarks and future work are also presented.

Avionics Testing with Artificial Intelligence Support

  • Autoři: doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: 2020 AIAA/IEEE 39th Digital Avionics Systems Conference (DASC) Proceedings. Piscataway: IEEE Service Center, 2020. ISSN 2155-7195. ISBN 978-1-7281-9825-5.
  • Rok: 2020
  • DOI: 10.1109/DASC50938.2020.9256563
  • Odkaz: https://doi.org/10.1109/DASC50938.2020.9256563
  • Pracoviště: Centrum umělé inteligence
  • Anotace:
    This paper describes a concept allowing for automated testing of avionics installed on a test bench where concepts of Artificial Intelligence are used. This test bench technology provides means for fast discovery of changes in behavior of new releases of avionics software where feature corrections can lead to modified behavior of other functions. The tested avionics is installed in a simulator test bench allowing to simulate behavior and systems of the respective airplane type. The test bench allows the pilot himself to test the functionality which can be repeated by the automation system itself. The technology behind the simulator collects all the data from the test bench internal buses under different conditions to be used as a reference to identity deviations from expected behavior of the avionic systems. The Artificial Intelligence methods used in our approach include state space search algorithms for determination of required control routines and data learning related to identification of deviations in behavior.

Comparison of Flight-Planning Algorithms in View of Certification Requirements

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Udatný, V.
  • Publikace: IEEE/AIAA 38th Digital Avionics Systems Conference (DASC). Irvine, CA: IEEE, 2019. p. 1-1274. 1. vol. 1. ISSN 2155-7209. ISBN 978-1-7281-0649-6.
  • Rok: 2019
  • Pracoviště: Centrum umělé inteligence
  • Anotace:
    In this paper, a comparison of flight path planning algorithms is presented to solve three-dimensional planning problem for a typical flight path scenario for UAV indoor and outdoor applications with oversight into general aviation and paid transport. The algorithms consider the performance of the navigation sensors and expected departure and arrival procedures which use the existing navigation means (VOR, NDB, ILS, GPS). The cruise situation is simplified to GPS navigation and obstacle avoidance. We choose to analyze the selected algorithms from the point of view of the certification issues according to the existing HW and SW requirements on determinism and time consumption. The analysis is made from the point of view of DO-178 standard. We describe the Artificial Intelligence phenomena and discuss the determinism of the currently used algorithms for flight-path panning. Within our work we focus on and summarize advantages and disadvantages of Breadth First Search, A*, Iterative Deepening A*, Theta*, and RRT* algorithms. Their reasoning process and path selection methodology with perspective of aerospace requirements are evaluated. Our main focus will be on the randomization element and uncertainty of these algorithms. We will also describe selected evaluation parameters required by FAA and EASA Technical Standard Order (TSO) documents on electronic systems and what are the conflicts between these requirements and the natural principle of the existing path-planning algorithms.

Sanace skalních svahů - pasivní kompozitní prvky

  • Autoři: Štefaňák, J., Chalmovský, J., Girgle, F., Míča, L., Štěpánek, P., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: Sanace skalních svahů - pasivní kompozitní prvky.. Brno: Akademické nakladatelství CERM, 2019. p. 1-127. 1. vol. 1. ISBN 978-80-7623-015-6.
  • Rok: 2019
  • Pracoviště: Centrum umělé inteligence
  • Anotace:
    Publikace se věnuje problematice sanace skalních svahů za použití kompozitních prvků. Její obsah v sobě shrnuje poznatky získané z odborné domácí i zahraniční literatury spolu s výsledky získanými z řešení projektu „FV 10505 Inteligentní kompozitní kotevní prvek“ finančně podporovaného Ministerstvem průmyslu a obchodu České republiky. Sanace skalních svahů je standardní aplikací používanou v české geotechnické praxi. Hlavním materiálem požívaným pro sanaci je ocel. V současné době se však stále více začínají uplatňovat i v této oblasti kompzitní materiály, které mají řadu výhod, ale i nevýhod. Proto je nutné jim věnovat pozornost a získat tak nové poznatky, které by umožnily lépe pochopit chování kompozitních prvků instalovaných ve skalním svahu. Sanační prvky mohou působit ve skalním svahu aktivně (např. horninová kotva) nebo pasivně (např. horninový hřebík). Předkládaná publikace se zaměřuje zejména na pasivní prvky.

Any-Time Trajectory Planning for Safe Emergency Landing

  • DOI: 10.1109/IROS.2018.8594225
  • Odkaz: https://doi.org/10.1109/IROS.2018.8594225
  • Pracoviště: Katedra počítačů, Centrum umělé inteligence
  • Anotace:
    Loss of thrust is a critical situation for human pilots of fixed-wing aircraft which force them to select a landing site in the nearby range and perform an emergency landing. The time for the landing site selection is limited by the actual altitude of the aircraft, and it may be fatal if the correct decision is not chosen fast enough. Therefore, we propose a novel RRT* -based planning algorithm for finding the safest emergency landing trajectory towards a given set of possible landing sites. Multiple landing sites are evaluated simultaneously during the flight even before any mechanical issue occurs, and the roadmap of possible landing trajectories is updated permanently. Thus, the proposed algorithm has the any-time property and provides the best emergency landing trajectory almost instantly.

Optical Measurement Methods for Attitude Determination of Unmanned Aerial Systems

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Yu, W.K., Klesa, J.
  • Publikace: 2018 IEEE/AIAA 37th Digital Avionics Systems Conference (DASC). IEEE (Institute of Electrical and Electronics Engineers), 2018. p. 1287-1293. ISSN 2155-7195. ISBN 978-1-5386-4112-5.
  • Rok: 2018
  • DOI: 10.1109/DASC.2018.8569298
  • Odkaz: https://doi.org/10.1109/DASC.2018.8569298
  • Pracoviště: Centrum umělé inteligence
  • Anotace:
    This article deals with a concept of attitude and position determination of ultra-small airplanes. We aim on evaluation of airfoil characteristics for very low Reynolds numbers. The work is significant for airplane performance evaluation especially with application of swarms of UAVs being released from bigger airplanes. We use a time-of-flight camera to determine the position and orientation of an ultra-small airplane. In the article, we evaluate multiple optical measurement methods, the principle of the airplane performance evaluation from the flight data and precision of this method using a time-of-flight camera.

A Precise Altitude Difference Measurement System for Terrain Mapping and Application in a Ducted-Fan Powered Airplane

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Theiner, R., Brabec, J.
  • Publikace: 2017 IEEE/AIAA 36th Digital Avionics Systems Conference (DASC). New York: IEEE, 2017. Advancing Technology for Humanity. ISSN 2155-7195. ISBN 978-1-5386-0365-9.
  • Rok: 2017
  • DOI: 10.1109/DASC.2017.8102109
  • Odkaz: https://doi.org/10.1109/DASC.2017.8102109
  • Pracoviště: Katedra počítačů
  • Anotace:
    This article describes the assembly and performance of a differential pressure measurement system adapted to provide information about altitude difference. The system is being tested in different conditions and it is adapted for position angles measurement in a ducted fan-powered airplane. The main contribution of the article is a comparison of characteristics of pressure sensors suitable for differential measurement and consequently for altitude difference measurements. The proposed applications are precise large-scale terrain mapping and this article describes its usage on relatively small area given by size of the airplane that is flying at speeds higher than 100 km/h. The airplane design considerations are made to accommodate the proposed measurement system, which uses properties of standard atmosphere to determine the roll angle and the pitch angle of the airplane. We describe the details of the airplane that are necessary for the installation of the measurement system. The application on the airplane requires high precision sensors and installation. We describe the proposed principle of measurement as well as the data analysis and its performance under different conditions. These conditions include laboratory setup, UAV flight, an installation on a Cessna airplane, a stratospheric balloon and usage on a prototype of ducted fan powered airplane.

Independent Global Monitoring System for Remotely Piloted Aircrafts

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Bowen-Gaddy, J. E.
  • Publikace: 2016 IEEE/AIAA 35th Digital Avionics Systems Conference (DASC) Enabling Avionics for UAS/UTM (UAS Traffic Management). Piscataway, NJ: IEEE, 2016. pp. 1-9. ISBN 978-1-5090-5600-2.
  • Rok: 2016
  • Pracoviště: Katedra měření
  • Anotace:
    This article describes the design of a global monitoring system for remotely piloted aircrafts using a satellite, radio, and GSM datalink. The final solution aims for small, general-purpose drones weighing less than 20 kg, which could be engaged into an Internetof-Things concept. In this work we propose a solution for drone operation and crash monitoring, protection of flight-restricted areas, protection of urgent low-altitude flights (emergency), and a flight hours logging system for general purpose drones or remotely piloted airplanes. The article describes the certification process of current aerospace products to attempt to apply this certification process for RPAS. We define the categories of vehicles and specify for which ones our system is designed. Next we describe the data measurement and acquisition unit which measures flight data and transmits them to a ground database in real time. We compare the available technologies and provide reasoning for the selected solution where we specify the disadvantages of the selected technology and how we overcome those. The article provides description of material and data flow, which is related to our business model and what services we can provide to customers. Finally, the results of the system’s initial testing are provided.

THE PREDATOR (PRESSURE DIFFERENCE DEPENDENCY ON ALTITUDE VERIFICATOR) EXPERIMENT

  • Autoři: Lukačevič, J., doc. Ing. Pavel Pačes, Ph.D., Tůmová, Z., Trojan, O., Gabriel, M., Hampl, M.
  • Publikace: 67th International Astronautical Congress. International Astronautical Federation, 2016.
  • Rok: 2016
  • Pracoviště: Katedra měření
  • Anotace:
    The PREDATOR experiment aims at advancing aircraft navigation systems by verification of a new pressure difference measurement method. PREDATOR is an experiment conducted by a small team of students from the Czech Technical University in Prague within the BEXUS (Balloon EXperiments for University Students) programme and is fully supported by the European Space Agency. The objective of the experiment is to verify a new measurement method using an arrangement of pressure sensors in a very specific setting. That will be achieved by gathering measured data during the ascent and descent of a stratospheric balloon mounted on a gondola. Such a method (and experimental setting) has a wide range of use for further improvement of current AHRS (Altitude Heading Reference System) in aircrafts and can improve their navigation systems. The method is based on a previous research at Czech Technical University in Prague and has already been tested in conditions of a scientific laboratory, in a natural environment using UAV, as well as in a small commercial aircraft and the measured data so far suggest the validity of the method. Throughout the year 2016, further measurements are being conducted in order to gather more data and increase the relevance of the research.

HIGH-FIDELITY TERRAIN LANDSCAPE EFIS VISUALIZATION IN COMPARATIVE NAVIGATION TO SOLVE DISORIENTATION

  • Autoři: Mazůrek, P., doc. Ing. Pavel Pačes, Ph.D., Filla, J.
  • Publikace: DASC - 34th Digital Avionics Systems Conference "Impact of Global Mandates on Avionics Research and Development". Reston, VA: AIAA, 2015. ISSN 2155-7195. ISBN 978-1-4799-8940-9.
  • Rok: 2015
  • DOI: 10.1109/DASC.2015.7311390
  • Odkaz: https://doi.org/10.1109/DASC.2015.7311390
  • Pracoviště: Katedra měření
  • Anotace:
    Safety in air transportation resides in effective pilot training and displays to reduced pilot errors. Many aviation accidents come from cockpit miscommunication which requires analysis of shared situation awareness between aviators which is a current research and development direction using the Czech Technical University (CTU) cockpit simulator. Specifically, the CTU simulator utilizes enhanced feedback to coordinate the control of the cockpit joysticks. With modern transport aircraft, the coordination between the pilot and the co-pilot enables safe flight, redundancy, as well as shared responsibilities. Teaming becomes challenging during avionics malfunctions as not all pilots have the same situation awareness. Thus, the Czech Technical University flight simulator has been designed to study the effects of team piloting and explore situations that require communication between the pilot and co-pilot to mitigate and recover from aircraft malfunctions. In this paper, we discuss the current design and implementation that makes use of hardware (stick control), software (visualization), and evaluation (human factors) to explore situations in which the team has a shared awareness or worse, when there is cognitive dissonance between the pilots in assessing the situation. Example cases are studied in which an avionics malfunction happens and both pilots are presented with similar and conflicting information to determine how they respond. CTU-design software called FlightGear Connector, described in the paper is freely available at Bitbucked or SourceForge. The performed analysis shows discrepancy in the pilot model determination which we would like to further explore and possibly use for pilot test scenario validation.

PILOT CONTROLLER DESIGN USING THE CTU FLIGHT SIMULATOR FOR SHARED SITUATION AWARENESS

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Jalovecky, R., Blasch, E., Staněk, J.
  • Publikace: DASC - 34th Digital Avionics Systems Conference "Impact of Global Mandates on Avionics Research and Development". Reston, VA: AIAA, 2015. p. 3E31-3E310. ISSN 2155-7195. ISBN 978-1-4799-8940-9.
  • Rok: 2015
  • DOI: 10.1109/DASC.2015.7311409
  • Odkaz: https://doi.org/10.1109/DASC.2015.7311409
  • Pracoviště: Katedra měření
  • Anotace:
    Safety in air transportation resides in effective pilot training and displays to reduced pilot errors. Many aviation accidents come from cockpit miscommunication which requires analysis of shared situation awareness between aviators which is a current research and development direction using the Czech Technical University (CTU) cockpit simulator. Specifically, the CTU simulator utilizes enhanced feedback to coordinate the control of the cockpit joysticks. With modern transport aircraft, the coordination between the pilot and the co-pilot enables safe flight, redundancy, as well as shared responsibilities. Teaming becomes challenging during avionics malfunctions as not all pilots have the same situation awareness. Thus, the Czech Technical University flight simulator has been designed to study the effects of team piloting and explore situations that require communication between the pilot and co-pilot to mitigate and recover from aircraft malfunctions. In this paper, we discuss the current design and implementation that makes use of hardware (stick control), software (visualization), and evaluation (human factors) to explore situations in which the team has a shared awareness or worse, when there is cognitive dissonance between the pilots in assessing the situation. Example cases are studied in which an avionics malfunction happens and both pilots are presented with similar and conflicting information to determine how they respond. CTU-design software called FlightGear Connector, described in the paper is freely available at Bitbucked or SourceForge. The performed analysis shows discrepancy in the pilot model determination which we would like to further explore and possibly use for pilot test scenario validation.

Summary of Avionics Technologies

  • Autoři: Blasch, E., doc. Ing. Pavel Pačes, Ph.D., Kostek, P., Kramer, K.
  • Publikace: IEEE Aerospace and Electronic Systems Magazine. 2015, 30(9), 6-11. ISSN 0885-8985.
  • Rok: 2015
  • DOI: 10.1109/MAES.2015.150012
  • Odkaz: https://doi.org/10.1109/MAES.2015.150012
  • Pracoviště: Katedra měření
  • Anotace:
    Avionics (aviation electronics) has been evolving for over a century which had a surge during the late 1940s from both World War II and the founding of the Professional Group on Airborne Electronics (PGAE) in February 1955 [14]. Since that time, IEEE has been a source of literature contributions in avionics from the inaugural Aeronautical and Navigational Electronics (ANE) group followed by the name changes to the Aerospace and Navigational Electronics (ANE) to the current Aerospace and Electronics Systems Society (AESS). The society's name variations demonstrate the importance of electronics in support of aviation developments.

BMW IDRIVE AUTOMOTIVE HID DEVICE IN EFIS CONTROL

  • Autoři: Suchý, J., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: 33rd DASC - Digital Avionics Systems Conference. Reston, VA: AIAA, 2014. ISSN 2155-7209. ISBN 978-1-4799-5001-0.
  • Rok: 2014
  • DOI: 10.1109/DASC.2014.6979432
  • Odkaz: https://doi.org/10.1109/DASC.2014.6979432
  • Pracoviště: Katedra měření
  • Anotace:
    This paper describes usage of a BMW electronic system controller called iDrive to control the Electronic Flight Instrument System onboard of an airplane. In this work we analyzed properties of the BMW iDrive controller and its usability for aerospace applications in the area of small airplanes to control multiple display units. The automotive industry requires demanding certification procedures and the operation environment conditions are comparable to aerospace. The BMW unit is not the only one available on the market. We compare different automotive controllers and propose methods how to use these products for EFIS control. Usually the EFIS provides multiple knobs to set the internal parameters. In our work we bind the buttons and rotational knobs available on the iDrive controller to the EFIS menus and functions. We describe the design of the unit, its communication protocol, methods we used to get its operation data, methods how to interconnect the iDrive with the rest of the system and we propose a communication protocol which is used to share one controller on multiple EFIS systems. The EFIS system is briefly described in our paper. Last part of the paper deals with description of the test performed with help of the pilots in order to get an overview about the controller usability.

Emergency Landing Site Location Using Aerial Image Segmentation

  • Autoři: Levora, T., Bruna, O., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: ICAS Proceedings. St. Petersburg: ICAS, 2014. ISBN 3-932182-80-4.
  • Rok: 2014
  • Pracoviště: Katedra měření
  • Anotace:
    This paper is focused on the aerial image segmentation for the emergency landing purposes. The goal of the described method is to segment the whole given image into homogeneous regions. This paper is split into two parts, the first one describes the algorithm for a determination of classes number and the second one describes the image segmentation method. The segmentation is based on the Expectation-Maximization algorithm for the Mixture of Gaussians with the feature vector containing pixel color and position and texture of pixel neighborhood.

Magnetometer Data Fusion Algorithms Performance in Indoor Navigation: Comparison, calibration and testing

  • Autoři: Busato, A., doc. Ing. Pavel Pačes, Ph.D., Popelka, J.
  • Publikace: Metrology for Aerospace - 2014 IEEE International Workshop - Proceedings. Piscataway: IEEE, 2014. pp. 388-393. ISBN 978-1-4799-2069-3.
  • Rok: 2014
  • DOI: 10.1109/MetroAeroSpace.2014.6865955
  • Odkaz: https://doi.org/10.1109/MetroAeroSpace.2014.6865955
  • Pracoviště: Katedra měření
  • Anotace:
    This article describes usage of magnetometer sensors in data fusion algorithms for indoor navigation. A wireless sensor device was created to perform experiments. Multiple sensors were tested and their performance is compared among each other. The calibration algorithms are introduced and applied on the measurements while the results are compared. Finally, the magnetometer data are used to control gyroscopically stabilized platform and the performance of the stabilization is discussed. In the article we introduce a method for automatic compensation of the magnetometer induced errors and provide data which led to the method definition.

MAGNETOMETER WITH AN AUTOMATIC DISTORTION COMPENSATION AND ITS USAGE FOR INS AIDING

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Kopenec, J., Popelka, J.
  • Publikace: 33rd DASC - Digital Avionics Systems Conference. Reston, VA: AIAA, 2014. ISSN 2155-7209. ISBN 978-1-4799-5001-0.
  • Rok: 2014
  • DOI: 10.1109/DASC.2014.6979459
  • Odkaz: https://doi.org/10.1109/DASC.2014.6979459
  • Pracoviště: Katedra měření
  • Anotace:
    In this paper we describe a new magnetometer sensor head which is capable to measure the complete calibration circle as one data sample. The new sensor allows for online determination of hard and soft iron distortions and its usage to compensate for their effect on the heading measurement. It provides capability to the magnetometer to compensate for local distortions caused by sensor/aircraft assembly. We describe the construction of the sensor and the influence of the local magnetic field changes will be illustrated. The proposed solution leads to a sensor array and we will describe construction of the single unit and its graphical interface. Then the results provided by the new sensor concept will be presented and the performance of this approach will be compared. At the end we provide method of utilizing the compensated data into an IMU mechanization algorithm where it is used to determine offsets and scale factors of the IMU inertial sensors.

Ověření vhodnosti využití dvou výškoměrů pro určování polohových úhlů

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Popelka, J.
  • Publikace: MDS PSL 2014 - 14. mezinárodní vědecká konference Meření, diagnostika, spolehlivost palubních soustav letadel. Brno: Univerzita obrany, Fakulta vojenských technologií, 2014. pp. 15-31. ISBN 978-80-7231-970-1.
  • Rok: 2014
  • Pracoviště: Katedra měření
  • Anotace:
    Tento článek popisuje záměr použít dvou barometrických výškoměrů pro měření polohových úhlů na letounu. Jedná se o podélný sklon a příčný náklon. Princip měření využívá vlastností standardní atmosféry, kde tlak klesá s rostoucí nadmořskou výškou. Výšky měřené pomocí dvou výškoměrů umožňují určit jejich vzájemnou vertikální diferenci. V případě, že známe nejkratší vzdálenost mezi výškoměry, tak můžeme vypočítat související polohový úhel. Existuje několik způsobů, jak sestavit systém měření polohových úhlů pomocí tohoto principu a jedním z možných řešení je použití dvou absolutních snímačů tlaku. V tomto případě je přesnost snímačů tlaku rozhodující parametr. V tomto článku si popíšeme senzorové moduly s bezdrátovým rozhraním a potřebnými senzory a budeme hodnotit jejich výkonnost v navrhovaném systému pro měření polohových úhlů. V článku se zaměříme na porovnání dvou snímačů tlaku. První z nich je levný MEMS snímač LPS001DL bez certifikace pro letecké aplikace a druhý je SP82, který je často používán pro digitální výškoměry (air data computer) pro letecké aplikace. Tento článek popisuje bezdrátové měřicí moduly, datové rozhraní, mechanismus výměny dat s řídicí stanicí a výsledky měření, které jsou statisticky zpracovány a porovnány s očekávánými výsledky. Článek shrnuje technické a ekonomické výhody a nevýhody tohoto způsobu měření polohových úhlů a jejich použitelnost pro letectví.

Path Planning for Ultralights under Emergency Conditions

  • Autoři: Levora, T., Bruna, O., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: ICAS Proceedings. St. Petersburg: ICAS, 2014. ISBN 3-932182-80-4.
  • Rok: 2014
  • Pracoviště: Katedra měření
  • Anotace:
    The aim of this work is to design a path planning algorithm for ultralights under emergency conditions, mainly in engine failure situations. The pilot priority in such situation is to locate emergency landing site and perform landing. This article describes a method which is able to plan the flight path from the current aircraft position to the landing site. The flight path is planned with respect to the airplane kinematic model and aerodynamic limitations. The path planning algorithm is inspired by the RRT (Rapidly-exploring Random Tree) method.

PILOT TIMELINESS OF SAFETY DECISIONS USING INFORMATION SITUATION AWARENESS

  • Autoři: Blasch, E., doc. Ing. Pavel Pačes, Ph.D., Leuchter, J.
  • Publikace: 33rd DASC - Digital Avionics Systems Conference. Reston, VA: AIAA, 2014. ISSN 2155-7209. ISBN 978-1-4799-5001-0.
  • Rok: 2014
  • DOI: 10.1109/DASC.2014.6979525
  • Odkaz: https://doi.org/10.1109/DASC.2014.6979525
  • Pracoviště: Katedra měření
  • Anotace:
    Information fusion includes interaction between users (e.g., pilot’s) and machines (e.g., aircraft). As popularized by Boyd; the observe, orient, decide, act (OODA) paradigm captures a user’s decision making ability. The OODA model has been used as a method of a pilot’s situation awareness (SAW) in flying an aircraft. Improvements to the OODA model include the SAW model of perception, comprehension, and forecasting of events. SAW can include waypoint analysis, detecting emerging threats, as well as terrain navigation. In this paper, we analyze the timeliness of pilot actions to augment flight safety using the cognitive OODA (C-OODA) for engine outages. In a critical maneuver scenario, data collected and analyzed with the C-ODDA highlight pilot lead, immediate, delay, and no action responses which could shed light on cockpit control warnings.

STATISTICAL EVALUATION OF MULTIPLE LOW-COST MEMS SENSORS FOR ALTITUDE MEASUREMENT

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Suchý, J.
  • Publikace: 33rd DASC - Digital Avionics Systems Conference. Reston, VA: AIAA, 2014. ISSN 2155-7209. ISBN 978-1-4799-5001-0.
  • Rok: 2014
  • DOI: 10.1109/DASC.2014.6979479
  • Odkaz: https://doi.org/10.1109/DASC.2014.6979479
  • Pracoviště: Katedra měření
  • Anotace:
    This paper describes determination of airplane position angles by usage of five Attitude Heading and Reference Systems based on Micro-Electro-Mechanical System pressure sensors. The measurement relates to the properties of the standard atmosphere where the pressure descends with increasing altitude. Because the precision of the measurement strongly depends on the sensor performance the MEMS sensors usually do not provide usable outputs. In this paper we evaluate possibility to use a sensor array whose outputs are statistically evaluated and processed in order to acquire information necessary for altitude measurements and whose outputs will be compared with precision which is required for aviation. The article describes the wireless sensor modules, the data interface and the mechanism used for data exchange with a control station. Last part of the paper deals with possibility to use the statistically processed data from the set of modules for position angles measurements. We summarize technical and economic advantages and disadvantages of this method of positional angles measurement and their applicability for aviation especially for a new concept of blended-wing-body aircrafts.

A Complete Performance Tests of an Analogue Sun Sensor with Improved Linearity, Variable Slit and Shutter Distance

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Cabrera, J., Fellowes, S.
  • Publikace: 64th International Astronautical Congress - IAC2013. Graz: International Astronautical Federation, 2013. pp. 8044-8060. ISSN 0074-1795. ISBN 978-1-62993-909-4.
  • Rok: 2013
  • Pracoviště: Katedra měření
  • Anotace:
    This work summarizes lessons learned gained after performing analysis of existing sun sensor parameters and measurement of a complete set of characteristics of an analogue sun sensor whose design allows changing width of its slit and the height of the slit over the sensing element. The width of the sensor slit and the slit distance from the sensing element has been changed and the sensing element performance was recorded. The article introduces a method of testing and equipment used to determine an optimal arrangement of the sun sensor, including sun light simulator. While the analogue sun sensor has non-linear characteristics, a method which improves sensor linearity is introduced. This method introduces different shapes of the sensing elements to cope with changing response of the solar cell modules. There were multiple shapes tested including sinusoidal and exponential shapes that were compared with commonly used linear arrangement. The article summarizes recommendations for the sensing element optimal shape together with general advices about shutter which were derived from the measurement results. The optimal sun-sensor design is now being considered for a small satellite platform used mainly for education purposes and a university cube sat mission.

A Tool for Objective Evaluation of Pilots’s Ability to Determine Dangerous Flight Situations

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Hruška, M., Bruna, O.
  • Publikace: DASC 2013 - 32nd Digital Avionics Systems Conference 2013. Reston, VA: AIAA, 2013. pp. 6B51-6B512. ISSN 2155-7209. ISBN 978-1-4799-1538-5.
  • Rok: 2013
  • DOI: 10.1109/DASC.2013.6712617
  • Odkaz: https://doi.org/10.1109/DASC.2013.6712617
  • Pracoviště: Katedra měření
  • Anotace:
    The accident trends show the pilots do mistakes which can be divided into several groups where every year the percentage distribution of the accidents reaches similar values. The most accidents happen during landing and sometimes it is connected with engine failure. Some accidents happen after a chain of bad decisions which were made by the pilot. This article describes two approaches intended for accident rate mitigation. The first is a software tool which evaluates pilot’s performance during the flight with respect of the airplane type which was used for the flight. The second tool replays certain phase of a flight with requirement imposed on the pilot to recognize beginning of potentially dangerous situations.

Data Fusion of Inertial Measurement Unit and New Positional Angles Measurement System

  • Autoři: Popelka, J., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: ICMT'13 - Proceedings of the International Conference on Military Technologies. Brno: Univerzita obrany, 2013. pp. 893-900. ISBN 978-80-7231-917-6.
  • Rok: 2013
  • Pracoviště: Katedra měření
  • Anotace:
    This paper deals with possibility of data fusion from magnetometer and the new system for positional angles measurement for improving long-term stability of MEMS gyroscopes. First part of the paper describes the new positional angles measuring system, which is based on measuring pressure differences. This new system is independent on gravitate and centrifugal acceleration and on ambient pressure disturbances. Next part describes data fusion of signals from MEMS based inertial measurement unit, MEMS based magnetometer and the new positional angles measuring system. In this paper the scenario of implementing a group of standards IEEE 1451 for securing smart sensors functionality.

Experimental Stress Assessment in Biomedical Measurement Class

  • Autoři: Bruna, O., prof. Ing. Jan Holub, Ph.D., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: IDAACS 2013 - Proceedings of the 2013 IEEE 7th International Conference on Intelligent Data Acquisition and Advanced Computing Systems. Berlin: IEEE, 2013, pp. 99-102. pozn.: CD má na nálepce jiné ISBN: 978-1-4799-1427-2. ISBN 978-1-4799-1426-5.
  • Rok: 2013
  • DOI: 10.1109/IDAACS.2013.6662648
  • Odkaz: https://doi.org/10.1109/IDAACS.2013.6662648
  • Pracoviště: Katedra měření
  • Anotace:
    Classes at Czech Technical University in Prague focused on biomedical engineering are mainly working with physiological aspects of human body. Nowadays it becomes more common to include also psychological effects on human body, because a mental state of a person can affect the way he or she behaves and approaches problems. This paper describes a class which shows how human body can be affected by its state [1],[3],[4]. The aim is make students realize, that people’s mental state can influence state of body’s function. It is important, because the psychological state can affect decision making skills and erformance. In today’s society is very important to consider a human as a part of the loop.

Methods to measure pilot's ability to determine dangerous situations

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Bruna, O.
  • Publikace: ICMT'13 - Proceedings of the International Conference on Military Technologies. Brno: Univerzita obrany, 2013. pp. 993-1000. ISBN 978-80-7231-917-6.
  • Rok: 2013
  • Pracoviště: Katedra měření
  • Anotace:
    This article describes a set of tests intended to evaluate pilot's ability to recognize potentially dangerous situations with aim to improve flight safety. The goal of the present effort of government agencies is to maintain or increase the level of flight safety. Accidents reports were investigated and repeated accidents were identified together with the crucial moments that contribute to the accident. The scenarios are introduced to measure his ability to detect them and methods for measurement are described.

Performance Evaluation Of Two Altimeters Intended For Euler Angles Measurement

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Popelka, J.
  • Publikace: DASC 2013 - 32nd Digital Avionics Systems Conference 2013. Reston, VA: AIAA, 2013. pp. 8C31-8C312. ISSN 2155-7209. ISBN 978-1-4799-1538-5.
  • Rok: 2013
  • DOI: 10.1109/DASC.2013.6712653
  • Odkaz: https://doi.org/10.1109/DASC.2013.6712653
  • Pracoviště: Katedra měření
  • Anotace:
    This paper describes usage of two pressure altimeters to measure an airplane position angle, e.g. pitch or roll. The measurement relates to the properties of the standard atmosphere where the pressure descends with increasing altitude. The altitudes measured by two altimeters allow us to determine their mutual vertical difference. While we know the shortest distance between these two altimeters we can calculate the required positional angle of an airplane. There are multiple ways how to compose a measurement system using this principle. One possible solution is based on two absolute sensors. In this case the precision of the pressure sensors is the crucial parameter. In this article we describe sensor modules with wireless interface using two types of sensors and we evaluate their performance for the proposed position angle measurement application. There are two types of sensors compared in the article. First of them is a cheap MEMS sensor LPS001DL provided by ST microelectronics with no certification for aerospace applications and the second is an SP82 manufactured by Memscap company which is often used in digital altimeters (Air Data Computer) for aerospace applications. The article describes the wireless measurement modules, the data interface, the mechanism used for data exchange with a control station and the measurement results that are statistically analyzed and compared with expectations. The article summarizes technical and economic advantages and disadvantages of this method of positional angles measurement and their applicability for aviation.

Pilot's Interaction with a Glass Cockpit Navigation System

  • Autoři: Bruna, O., Levora, T., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: Communications in Computer and Information Science. 2013, 374 304-307. ISSN 1865-0929.
  • Rok: 2013
  • DOI: 10.1007/978-3-642-39476-8_62
  • Odkaz: https://doi.org/10.1007/978-3-642-39476-8_62
  • Pracoviště: Katedra měření
  • Anotace:
    Poster deals with interaction between pilots and navigation system of an ultra-light aircraft equipped with a glass cockpit. Glass cockpits are slowly replacing the gauges and dials used in small aircrafts and will play an important role in the future, because it is expected, it will replace them completely. Presented results are regarding the decision making, flight performance and pilot’s justification of his choice. Data can be used to determine, if the pilots prefer to follow the navigator or independent flight, how they perform as pilots with and without navigation advisor. Based on this objective and subjective data conclusions are made. The outcome are suggestions for improvement of navigational instruments aboard and discussion focusing on how to help pilots in emergency situations stating both positive and negative opinions regarding use of glass cockpits.

Pressure Based Reference System For Aircraft Attitude Measurement

  • Autoři: Popelka, J., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: DASC 2013 - 32nd Digital Avionics Systems Conference 2013. Reston, VA: AIAA, 2013. pp. 4C41-4C414. ISSN 2155-7209. ISBN 978-1-4799-1538-5.
  • Rok: 2013
  • DOI: 10.1109/DASC.2013.6712588
  • Odkaz: https://doi.org/10.1109/DASC.2013.6712588
  • Pracoviště: Katedra měření
  • Anotace:
    This paper proposes a new system for aircraft attitude measurements. This measurement system can provide attitude reference measurements, in the other words Euler angles: pitch and roll angles, by a set of modified AHRS units and is aimed for ultra-light category of aircrafts. The principle uses measurement of differential pressure between atmospheric static pressure and reference pressure. The static pressure is measured at tips of aircraft wings by differential pressure sensors with regards to the reference volume. Theory describing behavior of the gas in the closed reference volume is described in the first part of the paper. Two different arrangements of the pressure reference system are described with their advantages and disadvantages. These two arrangements are modeled in Matlab Simulink and various ambient and inner influences are discussed in this part of the paper. Realization of different measurement system arrangements are presented in the next part of this paper. Parameters of the differential pressure sensors for the best performance of pressure based reference system are identified and different methods of data fusion from pressure based measurement system and the one axial accelerometer are described and discussed in the fourth part of this paper. Finally, the results from a roll angle measurement with the help of the pressure based reference system acquired during a test in a wind tunnel are presented and discussed.

Subjective stress rating in use of efis systems on board of ultra light aircraft

  • Autoři: Bruna, O., Levora, T., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: ICMT'13 - Proceedings of the International Conference on Military Technologies. Brno: Univerzita obrany, 2013. pp. 979-984. ISBN 978-80-7231-917-6.
  • Rok: 2013
  • Pracoviště: Katedra měření
  • Anotace:
    This paper presents subjective results from experiment with focus on ultra-light aircraft (aircraft with MTOM<2250kg) pilots’ capability to recognize critical situation, mainly arising from inappropriate manoeuvres or engine failure resulting in emergency landing. At Czech Technical University in Prague was designed emergency landing assistant and virtual electronic flight information system (EFIS) used in glass cockpits. Glass cockpits are slowly replacing the gauges and will play an important role in the future. Some systems are also equipped with guidance systems to help pilot maintain correct flight level and to aid him with safe approach and landing. Experiment described in this paper tries to identify if pilots can miss a moment, where the aircraft and crew could get into dangerous situation which can possibly be resulting in accident. Benefits of EFIS systems with special software equipment are then discussed.

Tunnel in the Sky with Audio Commands Extension

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Levora, T., Bruna, O.
  • Publikace: ICMT'13 - Proceedings of the International Conference on Military Technologies. Brno: Univerzita obrany, 2013. ISBN 978-80-7231-917-6.
  • Rok: 2013
  • Pracoviště: Katedra měření
  • Anotace:
    The article describes extension of the currently used tunnel-in-the-sky navigation approach of an EFIS instrument by audio commands which should lower the pilot workload and necessity to divide his attention between head-down display and the outside word. While performing the visual rules flights pilots are required to look out from the cockpit instead of checking his EFIS display. We are trying to extend the EFIS functionality by audio commands which allow the pilot to fly along a predefined path. While there is more approaches like point to point navigation which advice a course of the flight and it is on the pilot how he fly from the first point to the second one in this article we try to define a scenario in which the pilot is guided by audio commands along a smooth path including strait parts and also turns. The article describes the set of selected audio commands, methods of audio commands generation and preliminary results from the test flight where tunnel-in-the-sky and audio commands navigation is compared.

Advanced Display and Position Angles Measurement Systems

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Popelka, J., Levora, T.
  • Publikace: ICAS 2012 - 28th Congress of the International Council of the Aeronautical Sciences - Proceedings. Brisbane: ICAS - the International Council of the Aeronautical Science, 2012. pp. 3875-3888. ISBN 978-1-62276-754-0.
  • Rok: 2012
  • Pracoviště: Katedra měření
  • Anotace:
    In this article we introduce a patented and a completely new concept of airplane orientation angles measurement system which is furthermore referred as a pressure reference system. The authors also propose an arrangement of a magnetometer unit with multiple sensors that perform online calibration of hard iron and soft iron distortions. These systems are mutually connected to a WiFi network with other modules, head-down and head-up displays. There is also description of common avionics system units and sensors and their relation to the new proposed system. General aviation accounts for about 77 percent of the total flight hours while the rest are routinely scheduled flights. General aviation operations range from short-distance flights in single engine light aircraft to long-distance international flights in private jets, aero-medical operations and flying for fun. Electronics onboard of the airplane nowadays costs around one third of the airplane total price which vary with the precision and capabilities of the electronics system. Demand for the more precise but low-cost navigation which could improve some safety issues is being solved by data fusion of different sets of low-cost micro-mechanical sensors. Mainly signals provided by global position system and triads of inertial measurement sensors are being investigated and tightly coupled. This combination is capable to provide position of the airplane and its orientation angles. This article presents a new system that provides new information about orientation angles which can be used within data fusion algorithms to increase precision of the displayed information.

Aerometrická vlečená sonda

  • Autoři: Auersvald, J., Draxler, K., doc. Ing. Pavel Pačes, Ph.D., Popelka, J.
  • Publikace: MDS 2012 - Měření, diagnostika, spolehlivost palubních soustav letadel. Brno: Univerzita obrany, Fakulta vojenských technologií, 2012, pp. 25-33. ISBN 978-80-7231-894-0.
  • Rok: 2012
  • Pracoviště: Katedra měření
  • Anotace:
    Tento článek pojednává o vývoji a realizaci vlečené aerometrické sondy, které probíhaly v letech 2010 až 2012 v laboratoři Leteckých a kosmických systémů Fakulty elektrotechnické Českého vysokého učení technického v Praze. Článek pojednává o konstrukci, základních charakteristikách a vybavení sondy, včetně jejího příslušenství. V závěru článku je rovněž nastíněno budoucí směřování v užití navrženého a zkonstruovaného zařízení.

Analyses of Triaxial Accelerometer Calibration Algorithms

  • DOI: 10.1109/JSEN.2011.2167319
  • Odkaz: https://doi.org/10.1109/JSEN.2011.2167319
  • Pracoviště: Katedra měření
  • Anotace:
    This paper describes three tri-axial accelerometer calibration algorithms using mathematical model of nine parameters and the fact that the sum of sensed acceleration should be always equal to gravity vector under stationary conditions. The advantage of proposed algorithms is that the process does not require precise platform or special calibration equipment. The sensor error model (SEM) of tri-axial accelerometer consists of three scale-factor errors, three non-orthogonality angles, and three offsets. Three different algorithms were tested - Levenberg-Marquardt and Thin-Shell algorithm, and algorithm based on Matlab function fminunc. The proposed calibration process and its algorithms were experimentally verified on five accelerometers. We performed various analyses of proposed algorithms and proved that the proposed algorithms were capable to estimate the parameters of SEM without a need of precise equipment usage, which was the main aim of our investigation.

IMU Aiding Using Two AHRS Units

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Popelka, J.
  • Publikace: DASC 2012 - 31th Digital Avionics System Conference - Proceedings. Piscataway: IEEE Operations Center, 2012. pp. 1-12. ISSN 2155-7209. ISBN 978-1-4673-1699-6.
  • Rok: 2012
  • DOI: 10.1109/DASC.2012.6382359
  • Odkaz: https://doi.org/10.1109/DASC.2012.6382359
  • Pracoviště: Katedra měření
  • Anotace:
    This paper describes usage of two modified attitude heading and reference systems whose two pressure sensors are used to provide a new source of altimetry information that allows determination of position angles and inertial measurement unit sensor error models. The system is called Pressure Reference System. The two collaborating units use MEMS based triads of gyroscopes, accelerometers, magnetometers and multiple pressure sensors each. The two modules with their pressure sensors allow us to perform altitude measurements at two places from which a position angle can be determined. The altimetry data are recalculated to the position angle that is stable in time and does not suffer by drift errors amplified by the numerical integration algorithm used in inertial measurement units. This new information is fed back to the module as a correction signal for MEMS sensors and it is used to remove their drift errors. The method used for data fusion is described in this paper together with error model identification method, a testing system, laboratory test procedure and its results.

Miniaturization and Sensor Fusion of a Measurement Unit for a Trailing Bomb

  • Autoři: Popelka, J., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: DASC 2012 - 31th Digital Avionics System Conference - Proceedings. Piscataway: IEEE Operations Center, 2012. pp. 1-9. ISSN 2155-7209. ISBN 978-1-4673-1699-6.
  • Rok: 2012
  • DOI: 10.1109/DASC.2012.6382272
  • Odkaz: https://doi.org/10.1109/DASC.2012.6382272
  • Pracoviště: Katedra měření
  • Anotace:
    This paper deals with possibility of increasing accuracy and long term stability of an inertial measurement unit based on MEMS sensors used in a trailing bomb probe. The probe uses an air speed sensor, an altimeter, angle of attack and angle of sideslip sensors, and a complete IMU composed of triads of MEMS gyroscopes, accelerometers and magnetometers appended with pressure and temperature sensors. While the pressure and temperature sensors are crucial for trailing probe application the IMU is used for the probe orientation estimation. Accuracy and long term stability of the aero-metrical sensors can be increased while complemented by positional angles measurement. This article describes a method for sensor error parameters determination by usage of stable values of other sensors in the measurement system. Main aim is to increase sensor's accuracy and long term stability by data fusion from gyroscope triad sensors and a vector magnetometer. The algorithm will be used to determine positional angles in future. A positional angle computing was tested on data acquired by inertial measurement unit iNemo, a development kit from ST Microelectronics. The measurement system is described in this paper with a brief description of all of its components. The results obtained by the computational algorithm are discussed in this paper. While the present version of the probe measurement system is large the authors propose its miniaturized version where the COTS pressure sensor was replaced by a more precise and custom made pressure sensors. The actual test system and the proposed unit are designed to employ smart sensor functionalities, such as plug & play, self-testing and self-description, based on IEEE1451 group of standards.

Performance of Smart Sensors Standards for Aerospace Applications

  • Pracoviště: Katedra měření
  • Anotace:
    This paper deals with data exchange according to a group of standards IEEE 1451, which runs between a smart sensor module TIM and a supervising system NCAP. The first part of the paper presents the most important idea of IEEE 1451 group of standards: Transducer Electronics Data Sheet, which is a smart sensor description structure in module memory. It also describes the method of exchanging data between the modules and method of storing data in module's memory. Next part describes a multi-platform library, which was created, tested and then described in this paper. The library defines data structures and implements functions for storing data and their exchanging between TIM and NCAP modules. The paper also presents a scenario where all the aircraft systems are equipped with the smart sensor interface in order to simplify maintenance and replace-ability of all units. Finally, all the smart sensor functionality is applied on an aerometric module connected to a PC through CAN bus.

Small Aircraft Emergency Landing Decision Support System - Pilots' Performance Assessment

  • Pracoviště: Katedra měření
  • Anotace:
    This paper describes the methodology for investigating the usability of an emergency landing decision support system for ultra-light aircraft pilots. The introduction covers the aim of the device, while section methodology describes what the goal was and how it was achieved. The evaluation discusses the interpretation of the data measured and interviewed outputs. This paper is concluded with our learning and suggests future work.

Small Aircraft Flight Safety Increasing Using Integrated Modular Avionics

  • Autoři: Levora, T., Bruna, O., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: DASC 2012 - 31th Digital Avionics System Conference - Proceedings. Piscataway: IEEE Operations Center, 2012. pp. 1-9. ISSN 2155-7209. ISBN 978-1-4673-1699-6.
  • Rok: 2012
  • DOI: 10.1109/DASC.2012.6382388
  • Odkaz: https://doi.org/10.1109/DASC.2012.6382388
  • Pracoviště: Katedra měření
  • Anotace:
    This paper describes an idea of one approach to small aircraft safety increasing. The project was founded as reaction on numbers of small simple-engine aircraft accidents in the Czech Republic and their usual reason - human factor. Pilots and schools in the Czech Republic recently started to use glass cockpits which can be used also in other way than pure EFIS. Glass cockpit system could be extended by appropriate safety software modules. Software modules can be used in critical situations for flight analysis and giving appropriate advices to the pilot. Under this project was developed simple module navigating pilot to landing site when engine fails. Paper describes first version of EFIS with mentioned modules and also summarizes idea of designing system including testing approaches.

Smart Sensor Data Processing for Aerospace Applications in Education Illustrated by a Small Satellite Platform Demonstrator

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Popelka, J., Marchitto, Emidio, Levora, T.
  • Publikace: DASC 2012 - 31th Digital Avionics System Conference - Proceedings. Piscataway: IEEE Operations Center, 2012. p. 1-8. ISSN 2155-7209. ISBN 978-1-4673-1699-6.
  • Rok: 2012
  • DOI: 10.1109/DASC.2012.6382274
  • Odkaz: https://doi.org/10.1109/DASC.2012.6382274
  • Pracoviště: Katedra měření
  • Anotace:
    This article describes a tasks for undergraduate students from the area of signal processing that is often used in aerospace for data fusion of different kinds of sensors onboard of an airplane or a spacecraft. It includes a Kalman filter merging angular rates, accelerations and vector of the magnetic field. These topics are illustrated on a remotely controlled educational platform and its internal Inertial Measurement Unit. The article describes a set of sequential topics that introduces students with Attitude Heading and Reference System data processing on a remotely controlled platform that contains all necessary sensors. The hands-on experiments with the remotely controlled platform presented in this article takes advantages of the existing technology and shifts the currently used educational approach to the more interactive level. We mainly describe an algorithm to calculate position angles from raw sensor data which is used within Attitude Heading and Reference Systems and we propose a new arrangement of the AHRS unit which uses self-calibrating magnetometer and the Pressure Reference System for pitch and roll angles measurements to remove influence of accelerations generated during the flight.

Standalone Trailing Probe for Aero metrical Measurements

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Popelka, J., Auersvald, J.
  • Publikace: DASC 2012 - 31th Digital Avionics System Conference - Proceedings. Piscataway: IEEE Operations Center, 2012. pp. 1-12. ISSN 2155-7209. ISBN 978-1-4673-1699-6.
  • Rok: 2012
  • DOI: 10.1109/DASC.2012.6382275
  • Odkaz: https://doi.org/10.1109/DASC.2012.6382275
  • Pracoviště: Katedra měření
  • Anotace:
    This article describes a design of a probe intended for aero metrical instrument testing which is being hanged under an airplane. The probe collects data in an undisturbed airfield and compares them with data provided by dashboard instruments. The differences reveal quality of an airplane prototype design during maiden flights. The most important flight instruments are an altimeter and an air speed indicator. These instruments can be tested by comparison with data from a trailing bomb probe. While commonly used probes fed pressure from the probe entry points up to the airplane cabin by pipes, the prototype described in this paper uses wireless data link to transfer data to a data acquisition unit. Beside the altitude and speed the probe also measures its angle of attack and angle of sideslip which are used onboard to compensate for errors caused by probe alignment within the airfield. The designed system consists of two parts: the probe itself and a winch mechanism. Because the probe sensors are standalone the measured data reflects exactly the situation at the probe entry points. It means the probe measurements have to be corrected with regards to the length of the wire released from the winch and also for the speed of flight that influences the angle between the horizontal axe of an airplane and the wire connecting the airplane and the probe. Because the winch mechanism introduces problems with mounting and data correction the probe is designed to allow direct mounting on the airplane wing after removing its tail stabilization part. This design feature prepares the probe to be used also as an entry point for the new system for position angles measurement. Precision of the probe, pros and cons of both methods are discussed in the article.

Surface Recognition for Emergency Landing Purposes

  • Autoři: Levora, T., Bruna, O., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: 63rd International Astronautical Congress - IAC2012. Naples: International Astronautical Federation (IAF), 2012. ISSN 0074-1795. ISBN 978-1-62276-979-7.
  • Rok: 2012
  • Pracoviště: Katedra měření
  • Anotace:
    The paper describes an idea and early stage research results of the project under Czech Technical University in Prague. The project is about to help improve safety in ultra-light aircraft transportation, here is introduced one of several modules solved under the project. This module is activated in the emergency situation – when the engine fails. The idea is to use glass cockpit of the aircraft to show pilot possible landing sites and recommended track. Determination of possible runways in the nature uses installed camera and image processing algorithms.

The CzechTechSat Project - Experimental University 2U-Format Picosatellite

  • Autoři: Laifr, J., Papaj, J., Houštecký, L., doc. Ing. Pavel Pačes, Ph.D., Plaček, V.
  • Publikace: THE 2012 4S SYMPOSIUM - Small Satellite Systems and Services. Noordwijk: ESA Publications Division, 2012. pp. C17-1-C17-11.
  • Rok: 2012
  • Pracoviště: Katedra měření
  • Anotace:
    The short-term mission electronics for the Low Earth Orbits (LEO) spacecrafts can be based on the Commercial Off-The-Shelf (COTS) components reducing significantly the total budget. The COTS parts are not usually radiation tolerant, but with certain approaches it can survive higher radiation doses enough to meet the mission requirements. The CzechTechSat is a student scientific project planned by the Czech Technical University in Prague, Czech Republic. Its purpose is to build a university picosatellite platform based on 2U CubeSat form factor to demonstrate approaches for mitigation of radiation influences on onboard electronic systems. Project is held on occasion of the QB-50 CubeSat mission. The aim of this paper is to present circuit design approaches of the Maximum Power Point Tracking regulator; Current-Mode DC/DC converter with over current protection, undervoltage lockout and voltage feedback regulation; low power Mission Computer with external Magnetoresistive RAM and ADCS electronics with magnetotorquers and reaction wheel drivers and sun sensors interfaces. Finally the autonomous switching mechanism for cold-redundant systems is introduced to be employed to prolong the functionality of the respective system. In the experiment we propose using of a three monitored identical electronic systems (e.g. COTS GPS receiver, AMR magnetometer, etc.). One fully stand-alone, and two cold-redundant equipped by the switching mechanism. Total time of operation will be measured and compared each other and with identical devices tested in the laboratory.

5-Loch-Sonde mit integrierter Sensorik zur Messung hochfrequenter Druckschwankungen

  • Autoři: Beutel, T., Niesel, T., Leester-Schadel, M., doc. Ing. Pavel Pačes, Ph.D., Buttgenbach, S.
  • Publikace: Mikrosystemtechnik-Kongress 2011. Berlin: VDE VERLAG GMBH Berlin, 2011, pp. 1-4. ISBN 978-3-8007-3367-5. Available from: http://www.mikrosystemtechnik-kongress.de/
  • Rok: 2011
  • Pracoviště: Katedra měření
  • Anotace:
    Bei der hier beschriebenen Anwendung werden mehrere mikrotechnisch hergestellte Silizium-Drucksensoren in einer 5-Loch-Sonde zur Vermessung von Strömungen verwendet. Die Sensoren, wurden von 3D-Mikrokraftsensoren [1] ab-geleitet, so dass sie in der Lage sind, Druckdifferenzen zwischen 100 Pa und 120 kPa aufzunehmen. Sie basieren auf dem piezoresistiven Effekt. Bei der Konstruktion der mechanischen, der pneumatischen sowie der elektrischen Anschlüsse wurde besonderer Wert auf die Reduzierung der benötigten Schlauchlänge gelegt. Die Dämpfung wird da-durch drastisch reduziert und auch hochfrequente Anteile der Druckschwankungen können gemessen werden. Mit die-ser Information kann auch der Anstellwinkel (AOA) und der Schiebewinkel (SSA) bestimmt werden. Das System kann in Verbindung mit einem Air Data Computer (ADC) als Frühwarnsystem vor Auftriebsverlust (Stall) eingesetzt werden und so die Sicherheit im Luftverkehr erhöhen.

Development of Platform for Measurement and Signal Processing of Navigation and Aerometric Data

  • Autoři: Ing. Martin Šipoš, Ph.D., Nováček, P., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: POSTER 2011 - 15th International Student Conference on Electrical Engineering. Praha: České vysoké učení technické v Praze, Fakulta elektrotechnická, 2011, pp. 1-5. ISBN 978-80-01-04806-1. Available from: http://radio.feld.cvut.cz/conf/poster2011/
  • Rok: 2011
  • Pracoviště: Katedra měření
  • Anotace:
    Attractive education and quality research results based on real-world conditions depend on the equipment, instrumentation and sensors which are available for students' bachelor thesis, diploma thesis, dissertations, individual and team projects. The main aim of this paper is the realization of mobile aeronautical platform for measurement of sensors data in real-world conditions; mainly navigation data (GPS, magnetometer, INS) and aerometric data (static and dynamic pressures). This platform allows evaluation of the signal processing methods using real measured data, and evaluation of devices developed by bachelor, master, and postgraduate students in real-world conditions. This mobile aeronautical platform is used for real data acquisition, innovation of laboratory courses curriculum, promotion of the project results and importance of modern data processing in aviation.

Integrated Modular Avionics Onboard of Small Airplanes - Fiction or Reality?

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Levora, T., Bruna, O., Popelka, J., Mlejnek, J.
  • Publikace: 30th DASC Digital Avionics Systems Conference. Piscataway: IEEE, 2011. p. 7A1-1-7A1-12. ISBN 978-1-61284-796-2.
  • Rok: 2011
  • DOI: 10.1109/DASC.2011.6096112
  • Odkaz: https://doi.org/10.1109/DASC.2011.6096112
  • Pracoviště: Katedra měření
  • Anotace:
    Integrated Modular Avionics begins a core part of aircraft electronic installations on military airplanes. Based on more available and powerful electronics this concept is introduced also in to the area of civil aviation despite of more demanding certification process. Modern electronics penetrate also into ultra-light class of airplanes that are more accessible to flying public. Accidents of small and ultra-light airplanes were analyzed in order to identify ways to improve flight safety of this category of airplanes. Proposed solutions and the main findings are introduced here together with the development, evaluation and various test results. This paper presents a set of tools that allow rapid development of IMA functions and of Synthetic Vision Information System displays. System evaluation is illustrated on an IMA function performing online search for the most suitable place for landing under emergency situations.

Laboratorní systém pro ilustraci principu stabilizace kosmických prostředků

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Nováček, P., Ing. Martin Šipoš, Ph.D.,
  • Publikace: MDS - Měření, diagnostika, spolehlivost palubních soustav letadel 2011 - Sborník příspěvků z 11.mezinárodní vědecké konference. Brno: Univerzita obrany, Fakulta vojenských technologií, 2011. pp. 145-164. ISBN 978-80-7231-828-5.
  • Rok: 2011
  • Pracoviště: Katedra měření
  • Anotace:
    Tento článek popisuje konstrukci a princip činnosti zařízení, které jednoduchým způsobem ilustruje funkci stabilizace hmotného tělesa v prostoru na základě změny momentu vyvozovaného reakčním kolem - gyroskopem. Tento princip je možné použít i v gravitačním poli Země na objektu zavěšeném na struně. Jedná se o stabilizaci v jedné ose. Článek popisuje konstrukci zařízení, jednotlivých elektronických modulů, jeho funkci a použití jako laboratorní úlohy za účelem rozvoje zájmu studentů o kosmické technologie.

Modular System for Attitude and Position Determination

  • Autoři: Nováček, P., Ing. Martin Šipoš, Ph.D., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: POSTER 2011 - 15th International Student Conference on Electrical Engineering. Praha: České vysoké učení technické v Praze, Fakulta elektrotechnická, 2011. pp. 1-5. ISBN 978-80-01-04806-1.
  • Rok: 2011
  • Pracoviště: Katedra měření
  • Anotace:
    Precise attitude and position determination is one of main tasks in navigation procedure. Nowadays, there is possibility to navigate military Unmanned Aerial System (UAS) accurately also in case of its flight on other side of the Earth. But such precise navigation system based on inertial sensors (angular rate sensors and accelerometers) is not only expensive, but also large-sized and it has high power consumption for proper functionality. Costs, power consumption and size together with area restriction limit usage of such system especially in military application. This paper describes such a modular system based on low-cost inertial sensors with aiding sensors (distance sensors, pressure sensors, and tilt sensors). Described modular system finds its utilization not only as navigation system of small UAS, but also as part of intelligent metal detector equipped as added discrimination ability or in robot and indoor navigation.

Modular System for Attitude and Position Estimation

  • Pracoviště: Katedra měření
  • Anotace:
    Estimation of position and attitude of the object in a certain area has wide applicability in many industrial fields and in light of development it is a crucial part of aeronautics, astronautics, and also robotics. Nowadays, there already exist technologies for precise determination of the position and attitude with the accuracy of 0.01 m in position and 0.01 deg. in attitude. Sensors used for precise positioning with requirements of long time functionality are very expensive, big-sized, and have high power consumption. Based on these aspects these sensors are unsuitable for mobile application. Furthermore, many sensors are area restricted and so for non-army application unavailable. Therefore, there is an effort of many research centers to develop methods to reach sufficient precision with readily available means. This effort requires an innovative approach in the field of both complex algorithms for data acquisition and the composition of sensors.

Pokročilé zobrazovací metody pro malá letadla

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Hajný, J., Popelka, J.
  • Publikace: MDS - Měření, diagnostika, spolehlivost palubních soustav letadel 2011 - Sborník příspěvků z 11.mezinárodní vědecké konference. Brno: Univerzita obrany, Fakulta vojenských technologií, 2011. pp. 165-178. ISBN 978-80-7231-828-5.
  • Rok: 2011
  • Pracoviště: Katedra měření
  • Anotace:
    V tomto příspěvku je čtenář seznámen s principy přenosu informací v palubních sítích malých letadel, přičemž hlavní důraz článek klade na moderní elektronické zobrazovače. V článku jsou představeny dva zobrazovací systémy. První systém je podobný v současnosti často používaným palubním elektronickým zobrazovačům. Druhý systém představuje zcela unikátní prototyp průhledového displeje, tzv. head-up dispelej s konkrétním popisem principu, konstrukce a parametrů. Průhledový display disponuje omezeným rozlišením, které je ale dostatečné pro zobrazení informací důležitých pro funkci bezpečného navedení na přistání v případě výskytu mimořádných situací.

Rozložení tlaků kolem závěsné referenční a Pitot-statické sondy a ověření měření polohových úhlů ve větrném tunelu

  • Autoři: Popelka, J., doc. Ing. Pavel Pačes, Ph.D., Auersvald, J., Hospodář, P.
  • Publikace: MDS - Měření, diagnostika, spolehlivost palubních soustav letadel 2011 - Sborník příspěvků z 11.mezinárodní vědecké konference. Brno: Univerzita obrany, Fakulta vojenských technologií, 2011, pp. 189-205. ISBN 978-80-7231-828-5.
  • Rok: 2011
  • Pracoviště: Katedra měření
  • Anotace:
    Tento článek se zabývá aerometrickými měřeními a sondami používanými pro tyto účely, se zaměřením na závěsné sondy pro měření výšky a rychlosti. V příspěvku je detailně popsané měření, které proběhlo v tunelu patřícímu Výzkumnému a zkušebnímu leteckému ústavu Praha-Letňany, a jeho výsledky. Toto měření mělo za cíl ověřit vlastnosti chování a rozložení tlaků nově navrhované závěsné sondy s průměrem 7 cm a sondy plánované pro použití v novém systému měření polohových úhlů. Pro měření je použitý aerometrický systém instalovaný do těla sondy, který je po rozšíření použitý i pro měření polohových úhlů. Naměřené hodnoty tlaků jsou porovnány s výsledky simulace proudění, které bylo provedeno v programu ANSYS.

Small Satellite Systems Control for University Curriculum

  • Pracoviště: Katedra měření
  • Anotace:
    This article describes an electro-mechanical laboratory model of a spacecraft dedicated to demonstrate selected principles currently used in space with special intent to attract people back to space technologies. The model represents part of a microsatellite that allows its stabilisation and controlled movement in one axis. With this microsatellite we are able to demonstrate: microsatellite stabilisation with help of reaction wheels, inertial measurement unit function with coordinate system transformations, data acquisition and wireless data transfer, control loop design, start tracker functionalities and algorithm development.

Smart Sensors Standards for Aerospace Applications - Demonstration and Development Library

  • Autoři: Popelka, J., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: ICMT'11 International Conference on Miltary Technologies 2011. Brno: Univerzita obrany, 2011, pp. 671-677. ISBN 978-80-7231-788-2.
  • Rok: 2011
  • Pracoviště: Katedra měření
  • Anotace:
    This paper deals with data exchange according to a group of standards IEEE 1451, which runs between a smart sensor module TIM and a supervising system NCAP. The first part of the paper presents the most important idea of IEEE 1451 group of standards. It also describes the method of exchanging data between the modules and method of storing data in module's memory. Next part describes a multi-platform library, which was created, tested and then described in this paper. The library defines data structures and implements functions for storing data and their exchanging between TIM and NCAP modules. The paper also presents a scenario where all the aircraft systems are equipped with the smart sensor interface in order to simplify maintenance and replace-ability of all units. Finally, all the smart sensor functionality is applied on an aerometric module connected to a PC through CAN bus and USB to CAN converter.

Temperature Effects and Non-linearity Corrections of Pressure Sensors

  • Pracoviště: Katedra měření
  • Anotace:
    This paper presents a method of correction temperature effects affecting pressure sensors used mainly for dynamic and static pressure measurements within air-data systems based on low-cost sensors. The principle uses an isochoric process (or a constantvolume process) during which a thermodynamic changes cause pressure shift within the constant volume of a closed system. The closed system is presented here as a volume formed from a blinded inlet of a pressure sensor whose output is used for measurement sensor output corrections. The article presents all the equations used for the temperature effects and nonlinearity corrections. The overall method of the environmental effects correction is presented on a test system and a prototype of an Air-Data Computer.

Use of Differential Air Pressure Sensor for Barometric Difference Altitude and Vertical Speed Measurement

  • Pracoviště: Katedra měření
  • Anotace:
    The paper describes use of a differential air pressure sensor in an aerometric aircraft system. The differential sensor is operated by a pressure switch controlled by an electric signal. This lay-out is used for altitude difference measurement corresponding to a pressure difference range of the used sensor. The atmosphere temperature is measured simultaneously with the pressure difference. The measured altitude is then given as a sum of individual altitude sectors corresponding to switch-over of the pressure switch. This method of altitude measurement is suitable for small altitudes so that the resulting error given as a sum of errors by measurements of individual sectors is small. An example is use of an unmanned aerial vehicle (UAV) when the altitude difference from a starting point does not exceed 1 000 m. The difference switch with pressure switch-over together with time interval measurement may be also used for vertical speed measurement.

A Combined Angle of Attack and Angle of Sideslip Smart Probe with Twin Differential Sensor Modules and Doubled Output Signal

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Čenský, T., Hanzal, V., Draxler, K., Vaško, O.
  • Publikace: IEEE Sensors 2010 - Proceedings. Stoughton, Wisconsin: IEEE Sensors Council, 2010. p. 284-289. ISSN 1930-0395. ISBN 978-1-4244-8168-2.
  • Rok: 2010
  • DOI: 10.1109/ICSENS.2010.5689866
  • Odkaz: https://doi.org/10.1109/ICSENS.2010.5689866
  • Pracoviště: Katedra měření
  • Anotace:
    This article presents a combined system for an angle of attack (AOA) and an angle of sideslip (AOS) measurements that will be integrated into an existing air data computer system (ADC) due to an early warning against loss of air lift followed by uncontrolled fall of an airplane. We present a set of probes for AOA and AOS measurement whose parameters, advantages and disadvantages are compared together with a newly developed smart probe. Within the project time span, some probe types were simulated in computational fluid dynamic (CFD) software and twelve probes were manufactured and tested. The most promising probe is described in details and compared with other types, its transfer characteristics depending on its orientation with respect to the airstream, velocity of the airstream and temperature. A unique sensor interconnection method resulting in double amplitude measurement that is based on asymmetric connection of differential pressure sensors is presented.

Fusion of Smart Sensor Standards and Sensors with Self-Validating Abilities

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Reinštein, M., Draxler, K.
  • Publikace: Journal of Aircraft. 2010, 47(3), 1041-1046. ISSN 0021-8669.
  • Rok: 2010
  • DOI: 10.2514/1.43735
  • Odkaz: https://doi.org/10.2514/1.43735
  • Pracoviště: Katedra měření
  • Anotace:
    Airborne applications require a high degree of reliability, which is typically assured by development guides, testing, quality checking and overall certification processes. Although these processes provide a high level of product safety and reliability, the electronic devices can fail for various reasons. One of the main present-day problems is incompatibility of the communication interfaces of the smart sensors. This paper proposes a way of using standardized IEEE1451 interface with the information necessary for sensor self-validation ability. The necessary data is saved within the memory of the extended TEDS standard. This article presents usage of the extended TEDS data on a servomechanism, actuator with a feedback loop (servomechanism), designed for an unmanned aircraft.

Integrovaná modulární avionika na palubách malých letadel - fikce nebo realita?

  • Autoři: doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: MDS - Měření, diagnostika, spolehlivost palubních soustav letadel 2010. Brno: Univerzita obrany, 2010. pp. 22-34. ISBN 978-80-7231-741-7.
  • Rok: 2010
  • Pracoviště: Katedra měření
  • Anotace:
    Integrovaná modulární avionika (IMA) se stává nedílnou součástí instalací avionického vybavení moderních vojenských letadel. Tento koncept je i přes problémy spojené s náročnější certifikací zaváděn i do oblasti civilního letectví na základě dostupnější a výkonnější elektroniky. Moderní elektronika proniká i do oblasti velmi malých a běžným lidem dostupných typů letadel. Tato prezentace se zaměřuje na definici jednotlivých bloků tvořících integrovanou modulární avioniku, kdy jednotlivé části a porovnání jsou ilustrovány příklady z praxe. Prezentace poukazuje na podobnost v současné době používaných elektronických systémů se systémy modulární avioniky, "smart" senzorů a zobrazovačů. Na závěr je představen IMA testovací systém, jehož význam je ilustrovaný na funkcí automatického vyhledávání vhodné plochy pro přistání.

Integrovaný systém měření výšky

  • Autoři: Řezníček, P., Draxler, K., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: MDS - Měření, diagnostika, spolehlivost palubních soustav letadel 2010. Brno: Univerzita obrany, 2010. pp. 141-147. ISBN 978-80-7231-741-7.
  • Rok: 2010
  • Pracoviště: Katedra měření
  • Anotace:
    Článek popisuje systém, který využívá diferenční senzor tlaku vzduchu k měření výškové diference

Introducing Students to Aerospace Board Information Systems Using an Embedded Graphics System Simulator

  • DOI: 10.1109/ICALT.2010.114
  • Odkaz: https://doi.org/10.1109/ICALT.2010.114
  • Pracoviště: Katedra měření
  • Anotace:
    A graduate-level engineering course in airborne sensor and control systems taught at the Czech Technical University in Prague under the title Board Information Systems takes a novel systematic and comprehensive approach to teaching airborne digital avionics systems, together with system certification and life-cycle operations. The course brings together materials from various sources to cover practical aspects of avionics systems ranging from design, prototyping, testing, certification and production through to maintenance. It prepares students to deal with a wide range of the type of real-world problems that they will meet in thein professional careers. This is a required course offered in the 10th semester as a part of the study programme in Airborne Information and Control Instrumentation (AICI) by the Department of Measurement. The course was redesigned with new lecture content, practical exercises and field trips. The course evaluation survey results from 2008 and 2009.

Flight Attitude Track Reconstruction Using Two AHRS Units under Laboratory Conditions

  • DOI: 10.1109/ICSENS.2009.5398341
  • Odkaz: https://doi.org/10.1109/ICSENS.2009.5398341
  • Pracoviště: Katedra měření
  • Anotace:
    The paper describes a performance analysis of two low-cost AHRS (Attitude and Heading Reference Systems), calibration procedures, and the verification of INS (Inertial Navigation System) mechanization algorithm using dedicated automatic measurement system based on a real-time flight simulation. The measurement system included the flight simulation software FlightGear (FG) that offered a wide range of aircraft dynamics and track simulation possibilities. The FG output data were converted into the form suitable for a servocontrolled Rotational-Tilt Platform (RoTiP) which provided corresponding motion for two AHRS units mounted on it and reference information from optical sensors. The output data of the AHRS units were collected, processed and evaluated to verify the units accuracy and reliability. The metodology and results based on the performance analyses are presented.

Realizace online systému sledování letadel v průběhu plachtařských závodů

  • Autoři: Mlejnek, J., doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: Sborník z 9. mezinárodní vědecké konference "Měření, diagnostika a spolehlivost palubních soustav letadel 2009". Brno: Univerzita obrany, Fakulta vojenských technologií, 2009, pp. 103-111. ISBN 978-80-7231-670-0.
  • Rok: 2009
  • Pracoviště: Katedra měření
  • Anotace:
    Tato práce se zabývá rozborem možností online přenosu telemetrických informací mezi pozemní stanicí a bezmotorovými letadly. Dále je navržen způsob zpracování těchto dat a jejich následná distribuce a přehledná prezentace pro veřejnost v síti internet. Při návrhu je řešení optimalizováno pro využití na plachtařských závodech a také na jeho minimální provozní náklady.

Sensors of Air Data Computers - Usability and Environmental Effects

  • Pracoviště: Katedra měření
  • Anotace:
    This paper compares static pressure sensors suitable for aircraft air data systems. Characteristics of selected sensors influenced by environmental effects are compared with regards to their price. The group of sensors was chosen in order to cover a wide range of sensor samples available on the market. The article compares characteristics of sensors manufactured by Freescale, the MPX series, Memscap SP82, Intersema MS5534, and samples from SensorTechnics and Honeywell. The measurement setup is also described in the article. Digital modules connected through the CAN bus and GPIB measurement instruments were used for data acquisition. The data was sampled through Matlab Data Acquisition System extended by our own CAN Aerospace Toolbox that is being developed at CTU in Prague. The article finally compares all tested sensors and presents possible calibration methods, in which temperature effects and non-linearity were taken into consideration.

Verification of IEEE1588 Time Synchronization in NASA Agate Data Bus Standard

  • Pracoviště: Katedra měření
  • Anotace:
    Time synchronization quality of measurement devices plays critical role under necessity of precise data sampling, e.g. for usage of the Kirchhoff Current Law. This article proposes new arrangement of aircraft inertial sensors, that are spread over an airplane construction and needs to be time synchronized. Generally a single signal wire is used for time synchronization for local networks or they rely on their internal timers. The IEEE standardized a time synchronization algorithm designed for packet network such Ethernet. In this paper we propose usage of IEEE1588 over the Agate data bus based on the CAN bus in order to synchronize group of inertial sensors. In addition precision of the time synchronization is measured and compared.

Advanced Implementations Techniques in Kalman Filtering

  • Pracoviště: Katedra měření
  • Anotace:
    This paper deals with advanced implementation techniques in Kalman filtering regarding the computational complexity and filter numerical stability. Implementation techniques were validated using a conventional Kalman Filter that was developed on real data from Servo Hitec HS-5955TG. Servo's target application is as actuator in unmanned aerial vehicle (UAV) Manta, currently under prototype development by VTUL. Aim of this project was to enhance the servo's self validating process by Kalman Filter in a way to meet the DO178 development guides. The actual servo model was developed using response test measurements and load measurements followed by autoregressive modelling.

Development Platform for Avionics Instrumentation

  • Pracoviště: Katedra měření
  • Anotace:
    The article describes a design and an implementation of a measuring and display system (EMS - Engine Monitoring System) designed for small sports and ultra-light aircrafts. The problem is concentrated on display instrument development. This article presents a software development platform for the EMS display system with its pros and cons. A method for development time and costs saving is presented in the article.

Distribuovaný systém řízení bezpilotního prostředku Mamok Manta

  • Pracoviště: Katedra měření
  • Anotace:
    V současné době dochází k značnému rozvoji v oblasti dálkové řízených létajících prostředků, bez přítomnosti pilota. Jejich výhodou je dlouhá výdrž nad rozlehlou kontrolovanou oblastí. Bezpilotní prostředky mohou být využívány pro vojenské účely např. ostraha hranic, nebo v civilním sektoru pro kontrolu např. stavu polí (USA, Brazílie) Tyto bezpilotní prostředky obsahují buď z části, nebo zcela automatický elektronický systém řízení přičemž pilot sedící v bezpečí řídícího stanoviště přikazuje pouze požadavky na změnu výšky, rychlosti nebo směru letu. Článek popisuje systémy podpory řízení bezpilotního prostředku Mamok Manta, který je vyvíjen firmou AVEKO Brno, odštěpným závodem LOM VTÚLaPVO ve spolupráci s katedrou měření ČVUT v Praze.

Fusion of Smart Sensor Standards and Sensors with Self-validating Abilities

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Reinštein, M., Draxler, K.
  • Publikace: 27th DASC Digital Avionics Systems Conference. St. Paul, Minnesota: IEEE, 2008. ISBN 978-1-4244-2208-1.
  • Rok: 2008
  • Pracoviště: Katedra měření
  • Anotace:
    In airborne applications the high degree of reliability is required. Typical methods for assuring the reliability are development guides (DO178), testing, quality checking (AS9100) and certification processes. Despite these processes provide high level of safety and reliability of the products, the electronic devices can fail from different reasons. Also, one of the main present problems today is incompatibility of communication interfaces of so called smart sensors. This article proposes fusion of smart sensor standard IEEE1451 and information necessary for sensor self-validation of sensor output. In this paper estimation of the feedback magnitude measured by an intelligent servomechanism system is presented. This system is being developed for a specific UAV application. The necessary data are saved within the TEDS memory of the extended IEEE1451 standard. In the paper, following topics are discussed: methods of magnitudes validation and estimation, standards of smart sensors, the ser

LUN 1794 Converter - Special Functions

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Jelínek, L., Jaroš, R.
  • Publikace: Sborník z 8. mezinárodní vědecké konference Měření, diagnostika a spolehlivost palubních soustav letadel. Brno: Univerzita obrany, Fakulta vojenských technologií, 2008. pp. 55-66. ISBN 978-80-7231-555-0.
  • Rok: 2008
  • Pracoviště: Katedra měření
  • Anotace:
    This article describes extension of current LUN1794 synchro/resolver to ARINC429 converter with a function of runway marker switches. This instrument is being used on the Czech Army's Mil Mi 171 as a signal converter from a gyro-magnetic compass GMK and two automatic radio compasses ARK UD and ARK 15 to ARINC429 digital words that are transferred into a Rockwell-Collins MFD MF255EF. Instrument also receives data packets and search for specific data with information about runway markers. All changes led to instrument modification called LUN1794.7. The main aim of this article is the instrument new environmental testing.

Signal Validation Techniques for Signals with Known Time Behaviour

  • Pracoviště: Katedra měření
  • Anotace:
    The article contains description of signal validation technique being used for validation of input signals in the area of so called smart sensors. The validation technique is explained at an example of simple sinusoidal signals that are common for information transfer in aeronautics. These signals are used for transferring angle of rotation for flight critical data including roll, pitch and yaw angles engaged in artificial horizons or in aircraft navigation for exchange of navigation angles. The validation algorithms are proposed in the form of Reusable Software Objects. This article also proposes methods of usage group of IEEE1451 standards for simplification of system interconnection with other systems.

Development of a IEEE 1451 Standard Compliant Smart Transducer Network with Time Synchronization Protocol

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Ramos, H.M., Ramos, P.
  • Publikace: IMTC/2007 IEEE Instrumentation and Measurement Technology Conference Proceedings. Warsaw: IEEE, 2007. ISBN 1-4244-1080-0.
  • Rok: 2007
  • Pracoviště: Katedra měření
  • Anotace:
    The IEEE 1451 family of standards defines how transducers can be mapped to a target network based on an object model defined independently of the network. Presently one of these standards, the IEEE 1451.2, is under a revision process and within the primary enhancements already defined, alternate physical layers are envisaged. This paper presents an original solution by implementing the Network Capable Application Processor (NCAP) in a PC and using the Universal Serial Bus (USB) to communicate with the Transducer Independent Interface (TIM). The IEEE 1588 (PTP) protocol is used to synchronize the real-time clock of two TIMs connected to the USB hub. Besides the design implementation of the proposed Transducer Independent Modules with USB communication, an application to determine the temporal precision of the two modules obtained with the protocol is also described in detail.

Development of a New Type of an Actuator for UAV

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Draxler, K., Ramos, M.
  • Publikace: MOSATT 2007, Proceedings of the International Scientific Conference "Modern Safety Technologies in Transportation". Košice: Slovak Transport Society at the Slovak Academy of Sciences, 2007. pp. 205-210. ISBN 978-80-969760-2-7.
  • Rok: 2007
  • Pracoviště: Katedra měření
  • Anotace:
    The article describes design of a new type of an actuator for UAVs aircrafts. The proposed actuator is based on the hobby servo, involves CAN bus interface and force feedback. The servo system is described in the paper, the electronic core, the regulator and the applicability of the proposed device as well. The IEEE1451 standard is used as the actuator interface and is also briefly described.

Flight Data Measurement System for Small Airplanes

  • Autoři: doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: Proceedings of Workshop 2007. Praha: České vysoké učení technické v Praze, 2007. ISBN 978-80-01-03667-9.
  • Rok: 2007
  • Pracoviště: Katedra měření
  • Anotace:
    This article deals with aerometric quantities measuring with MEMS (Micro-Electro-Mechanical Systems) pressure sensors. Article describes their advantages and disadvantages, suitable sensor selection and evaluation of chosen sensors. There is described a smart sensor design and verification. This smart device uses Freescale pressure sensors. At the end there is a brief description of aircraft display unit.

Intelligent Sensing in a Design of a Distributed Engine Control Unit

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., doc. Ing. Jan Roháč, Ph.D., Ramos, H.
  • Publikace: ICST 2007 - The 2nd International Conference on Sensing Technology. Palmerston North: Massey University, Institute of Information Sciences and Technology, 2007, pp. 205-210. ISBN 978-0-473-12432-8.
  • Rok: 2007
  • Pracoviště: Katedra měření
  • Anotace:
    This article describes design of an aircraft engine control system which is based on a distributed network of sensors and actuators. The IEEE1451 standard is described and used for sensors and actuators interconnection. The IEEE1451 implementations of a sample senor and an actuator device are also described. Time differences in the sample data acquisition are described in details.

LUN1794 Synchro/Resolver Converter Control Application

  • Autoři: doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: POSTER 2007. Praha: České vysoké učení technické v Praze, Fakulta elektrotechnická, 2007. pp. 1-4.
  • Rok: 2007
  • Pracoviště: Katedra měření
  • Anotace:
    In the word there is a lot of aircrafts with avionic systems build on the technology originated from the extinct Russian Empire. These aircrafts were made in the lands of East Block. These aircrafts are sold to the all parts of the new word now. There are sensors and cockpits instruments based on the mainly mechanical technology well known in that time. In present time there is a problem with general reconstruction of these airplanes in case of replacing old mechanical instruments by the new display systems provided by the manufacturers from Europe or USA. This paper describes device which is able to collect data from the sub set of sensors used in these aircrafts and convert collected data to the format commonly used at the modern avionic systems. The described device meets the Level C of the RTCA/DO178B. This paper also documents cooperation between Faculty of Electrical Engineering, Czech Technical University and DevCom LTD [1].

Practical Evaluation of Time Synchronization by the IEEE 1588 Standard on the USB Bus

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Draxler, K.
  • Publikace: IWCIT 2007 - International Workshop Control and Information Technology. Ostrava: VŠB - Technical University of Ostrava, 2007. pp. 83-88. ISBN 978-80-248-1567-1.
  • Rok: 2007
  • Pracoviště: Katedra měření
  • Anotace:
    The Precision Time Protocol (PTP) is a protocol defined in the IEEE 1588 standard that allows precise time synchronization of devices connected to network. This contribution describes two devices connected by the UniversalSerial Bus (USB) bus and synchronized with the PTP protocol. The contribution describes design, development and parameters evaluation of the final realized devices. Also the other related outputs, such as a LabView control application, LabView DLL interfacing, and IEEE1451.2 standard implementation, are described in detail.

Certifikace leteckých elektronických přístrojů a softwarového vybavení v podmínkách České republiky

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Draxler, K.
  • Publikace: Nové trendy rozvoja letectva - Zborník 7. medzinárodnej vedeckej konferencie. Košice: Slovenský letecký inštitút a. s., 2006, ISBN 80-8073-520-4.
  • Rok: 2006
  • Pracoviště: Katedra měření
  • Anotace:
    Příspěvek si klade za cíl seznámit v obecné rovině posluchače s aktuální situací v České republice v oblasti certifikace elektronických zařízení, určených pro letecký provoz. Osvětlena bude právní základna, o kterou se opírá letectví a certifikace leteckého vybavení v České republice. Popisovány jsou rozdíly v certifikaci přístrojů v oblasti malých, sportovních letadel a v kategorii všeobecného letectví. Dále pak budou posluchači seznámeni se standardy a doporučeními pro certifikaci softwarových a hardwarových částí elektronických zařízení. V závěru budou prezentovány v současnosti probíhající práce na leteckých elektronických zařízeních, které jsou realizovány laboratoří leteckých řídicích a informačních systémů.

Měření vzdušné rychlosti letu pomocí levných snímačů

  • Pracoviště: Katedra měření
  • Anotace:
    V příspěvku je proveden rozbor parametrů tenzometrického a kapacitního diferenčního senzoru tlaku vzduchu pro jejich využití k měření kalibrované rychlosti letu letadla. Rozbor vychází z naměřených závislostí výstupních signálů na tlaku vzduchu s uvažováním teplotní závislosti, tlakové hystereze a dlouhodobé stability snímačů. Dále je popsána konstrukce rychloměru s kapacitním snímačem Vegabar 14. V závěru jsou uvedeny výsledky měření na realizovaném funkčním vzorku.

MS Excel - jednoduchý prostředek pro sběr dat nejen na sběrnici GPIB

  • Pracoviště: Katedra měření
  • Anotace:
    Článek popisuje možnost sběru dat z přístrojů připojených ke sběrnici GPIB. Pro připojení přístrojů je využita knihovna Agilent IO Libraries, VISA a COM - Component Object Model. V článku je uveden podrobný návod na realizaci měření z multimetru HP34401A.

Utilization of Low Cost MEMS Pressure Sensors in Small and Ultralight Aircraft Avionics

  • Pracoviště: Katedra měření
  • Anotace:
    Pressure measuring guides aeronautics from the beginning. There are and will be used barometric altimeters in aircraft industry. The advantage of the mechanical instruments is well known and mastered technology. The disadvantages are technology demanding ness and price. The aim of this contribution is a study of possibilities of "aircraft pressures" measurement with low cost MEMS pressure sensors. Next point is analysis of this type sensor errors and methods used for improving accuracy.

Výškoměr pro malá letadla

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Draxler, K.
  • Publikace: Nové trendy v civilním letectví 2006 - Sborník příspěvků mezinárodního odborného semináře. Brno: VUT v Brně, Fakulta strojního inženýrství, 2006, pp. 117-122. ISBN 80-7204-450-8.
  • Rok: 2006
  • Pracoviště: Katedra měření
  • Anotace:
    Tento článek se zabývá měřením aerometrických veličin za využití MEMS (Micro-Electro-Mechanical Systems) snímačů tlaku, jejich výhodami a nevýhodami a výběrem snímačů vhodných pro realizaci výškoměru a ověřením jejich použitelnosti. Na závěr je popsána realizace výškoměru za použití tlakoměrů firmy Freescale, zhodnocení parametrů navrženého zařízení a krátký popis zobrazovací jednotky výškoměru.

Display Unit Designed for Small Sports Aircrafts

  • Autoři: doc. Ing. Pavel Pačes, Ph.D.,
  • Publikace: IWCIT 2005 - International Workshop Control and Information Technology. Ostrava: Technická univerzita, 2005, pp. 215-218. ISBN 80-248-0906-0.
  • Rok: 2005
  • Pracoviště: Katedra měření
  • Anotace:
    This paper deals with a design and an implementation of a display system (EDU - Engine Display Unit) designed for small sports and ultra-light aircrafts. The problem is concentrated on collecting and showing values from several types of different engine and flight data sensors that are commonly used in this aircraft category.

Engine Parameters Measurement and Display Unit for Small Sports and Ultra-light -aircrafts

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Mareš, V.
  • Publikace: Applied Electronics 2005 - International Conference Pilsen. Plzeň: Západočeská universita, 2005, pp. 257-260. ISBN 80-7043-369-8.
  • Rok: 2005
  • Pracoviště: Katedra měření
  • Anotace:
    This article describes a design and an implementation of a measuring and display system (EMS - Engine Monitoring System) destined for small sports and ultra-light aircrafts. The problem is concentrated on collecting and showing values from several types of different engine data sensors that are commonly used in this aircraft category. The work is focused on an utilization of common electronic parts, on economic point of view and on a possibility of simple reproduction of the whole system.

Systém měření a zobrazení parametrů motorů ultralehkých letadel

  • Autoři: doc. Ing. Pavel Pačes, Ph.D., Mareš, V.
  • Publikace: Sborník příspěvků 5. odborného semináře "Měření, diagnostika a spolehlivost palubních soustav letadel". Brno: Univerzita obrany, Fakulta vojenských technologií, 2005, pp. 113-119. ISBN 80-7231-022-4.
  • Rok: 2005
  • Pracoviště: Katedra měření
  • Anotace:
    Příspěvek se týká systému pro sběr motorových parametrů ultralehkých letadel. Jedná se o dvě elektronické jednotky. První z nich měří a sbírá příslušné veličiny a druhá se stará o zobrazení naměřených hodnot. V příspěvku je popsán návrh systému, jeho realizace a současné využití jako laboratorní úlohy.

Za stránku zodpovídá: Ing. Mgr. Radovan Suk