dr inż. Cezary Graczykowski

Zakład Technologii Inteligentnych (ZTI)
Pracownia Inżynierii Bezpieczeństwa (PIB)
stanowisko: adiunkt
telefon: (+48) 22 826 12 81 wew.: 432
pokój: 440
e-mail: cgraczyk

Doktorat
2012-06-28Inflatable Structures for Adaptive Impact Absorption 
promotor -- prof. dr hab. inż. Jan Holnicki-Szulc, IPPT PAN
649
 
Ostatnie publikacje
1.Graczykowski C., Pawłowski P., Exact physical model of magnetorheological damper, Applied Mathematical Modelling, ISSN: 0307-904X, DOI: 10.1016/j.apm.2017.02.035, Vol.47, pp.400-424, 2017

Streszczenie:

This paper attempts to fill the gap in the literature by introducing and discussing an enhanced physical model of the MR damper. The essence of the presented model is to combine the effect of compressibility of the MR fluid enclosed in each chamber with the effect of blocking the flow between the chambers in the case of a low pressure difference. As it will be shown, the concurrence of both considered phenomena significantly affects mechanical behaviour of the damper, influences its dissipative characteristics, and in particular, it is the reason behind the distinctive ‘z-shaped’ force–velocity hysteresis loops observed in experiments. The paper presents explanation of the observed phenomena, detailed derivation of the thermodynamic equations governing response of the damper, their implementation for various constitutive models of the magnetorheological fluid and, finally, formulation of the corresponding reduced and parametric models. Experimental validation shows that proper identification of physical parameters of the proposed mathematical model yields the correct shapes of force–velocity hysteresis loops.

Słowa kluczowe:

Magnetorheological fluid dampers, Smart fluids, Hysteresis modelling

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Pawłowski P.-IPPT PAN
35p.
2.Orłowska A., Graczykowski C., Gałęzia A., The effect of prestress force magnitude on the natural bending frequencies of the eccentrically prestressed glass fibre reinforced polymer composite beams, Journal of Composite Materials, ISSN: 0021-9983, DOI: 10.1177/0021998317740202, pp.1-14, 2017

Streszczenie:

This paper studies the effect of prestress force magnitude on natural frequencies and dynamic behaviour of eccentrically prestressed glass fibre reinforced polymer composite beams, including the theoretical background, numerical results and experimental verification. The term prestress indicates the initial tensile stress applied to the fibres embedded in selected external layers of the composite material. First, the paper presents the theoretical background of the finite element method modelling of prestressed composites. Then, the results of numerical simulations conducted for a five-layered glass-epoxy composite beam are presented. The natural frequencies corresponding to three initial bending modes are analyzed for different prestressing force levels and for different fibre volume content. Finally, the results are verificated by experimental modal analysis conducted on three different glass-epoxy composite specimens of various mechanical parameters. Both the numerical results obtained from finite element method and the experimental results obtained from experimental modal analysis reveal that the first bending frequency increases and the two subsequent bending frequencies decrease due to the prestressing force. The comparison of numerical and experimental data confirms the effect and allows to quantify the influence that the prestress force has on the natural frequencies of composites, which is an interesting and practically relevant phenomenon.

Słowa kluczowe:

Prestressed structures, laminated composites, prestressed reinforced composites, glass fibre reinforced polymer composite materials, vibrations, finite element method

Afiliacje autorów:

Orłowska A.-IPPT PAN
Graczykowski C.-IPPT PAN
Gałęzia A.-Warsaw University of Technology (PL)
30p.
3.Chikahiro Y., Ario I., Nakazawa M., Ono S., Holnicki-Szulc J., Pawłowski P., Graczykowski C., Watson A., Experimental and numerical study of full-scale scissor type bridge, Automation in Construction, ISSN: 0926-5805, DOI: 10.1016/j.autcon.2016.05.007, Vol.71, pp.171-180, 2016

Streszczenie:

Mobile Bridge™ is a deployable bridge that uses a scissors mechanism to achieve its useful structural form. The bridge has a compact size in its undeployed state and can be transported easily to where it is needed. Its rapid deployment makes this type of bridge very useful in areas struck by natural disasters by enabling vehicles to cross terrain that has been made impassable. In previous research, experiments and analyses were conducted on a small-scale bridge designed for pedestrians. In order to consider a bridge of increased size, it is necessary to assess whether design and analysis techniques of the small scale bridge are applicable to the full-scale one. In this paper, we consider a full-scale deployable bridge with a lower deck and two scissor units, that allows for a light vehicle to pass across. We have carried out a light vehicle loading test in order to investigate its basic structural characteristics. Furthermore, the paper presents the theoretical design method and numerical models based on the experimental work followed by validation and comparison with the obtained experimental values.

Słowa kluczowe:

Full-scale Mobile Bridge, Scissor type of emergency bridge, Scissors mechanism, Vehicle loading test

Afiliacje autorów:

Chikahiro Y.-Shinshu University (JP)
Ario I.-Hiroshima University (JP)
Nakazawa M.-Tohoku Gakuin University (JP)
Ono S.-Japan Construction Method and Machinery Research Institute (JP)
Holnicki-Szulc J.-IPPT PAN
Pawłowski P.-IPPT PAN
Graczykowski C.-IPPT PAN
Watson A.-Loughborough University (GB)
40p.
4.Graczykowski C., Mathematical models and numerical methods for the simulation of adaptive inflatable structures for impact absorption, COMPUTERS AND STRUCTURES, ISSN: 0045-7949, DOI: 10.1016/j.compstruc.2015.06.017, Vol.174, pp.3-20, 2016

Streszczenie:

The paper describes various approaches for the mathematical modelling of Adaptive Inflatable Structures (AIS) along with the corresponding numerical methods. The introductory part presents a general idea of adaptive impact absorption (AIA) and the concept of inflatable structures equipped with controllable valves serving for internal pressure control. Application of AIS for adaptive absorption of the impact loading is briefly explained. The paper focuses on diverse methods of modelling of inflatable structures, which are based on interaction between solid walls and fluid enclosed inside. Modelling of the solid walls is based on rigid body dynamics or initial-boundary value problem of solid mechanics. In turn, modelling of the fluid utilizes either classical equilibrium thermodynamics or Navier–Stokes equations. Consequently, four possible combinations of the above approaches are distinguished, precisely analyzed and applied for the modelling of different types of inflatable structures. Each model takes into account controllable valves, which requires introducing additional coupling between parameters defining the valves and selected results of the analysis. Corresponding numerical methods include classical methods of solving ordinary differential equations, finite volume method (FVM) applied for problems with mobile boundaries, finite element method (FEM) applied for problems involving additional ODEs and, finally, FEM coupled with FVM. Proposed numerical methods and software tools are utilized for the simulation of adaptive pneumatic cylinders, adaptive pneumatic fenders and membrane valves.

Słowa kluczowe:

Inflatable structures, Impact absorption, Fluid–structure interaction

Afiliacje autorów:

Graczykowski C.-IPPT PAN
40p.
5.Graczykowski C., Orłowska A., Holnicki-Szulc J., Prestressed composite structures – Modeling, manufacturing, design, COMPOSITE STRUCTURES, ISSN: 0263-8223, DOI: 10.1016/j.compstruct.2016.02.085, Vol.151, pp.172-182, 2016

Streszczenie:

This paper presents a preliminary research aimed at developing a comprehensive approach to modeling, manufacturing and optimal design of prestressed FRP composite structures. A simple and effective analytical model of prestressed composite is derived and further verified by two numerical models and the results of the experimental tests conducted on manufactured prestressed composite samples. The model reveals beneficial influence of prestress on strain and stress distribution in particular plies and resulting improvement of the global response of the composite. A design case-study of prestressed composite is presented and challenges related to design and application of more complicated composite prestressed structures are discussed.

Słowa kluczowe:

Prestressed structures, Laminated composites, Prestressed FRP reinforced composites

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Orłowska A.-IPPT PAN
Holnicki-Szulc J.-IPPT PAN
35p.
6.Graczykowski C., Holnicki-Szulc J., Crashworthiness of Inflatable Thin-Walled Structures for Impact Absorption, MATHEMATICAL PROBLEMS IN ENGINEERING, ISSN: 1024-123X, DOI: 10.1155/2015/830471, Vol.2015, pp.830471-1-22, 2015

Streszczenie:

The paper describes application of innovative, inflatable thin-walled structures for absorption of the impact loading and thoroughly investigates their crash characteristics. The proposed concept assumes inflation of thin-walled structures with compressed gas of appropriately adjusted pressure in order to improve their basic mechanical properties, enhance energy dissipation capabilities, and increase corresponding durability to impact loading. In the first part of the paper the influence of compressed gas on mechanical characteristics of aluminium beverage can is analysed experimentally and by the corresponding numerical simulations. The following section proposes and numerically verifies three diverse engineering applications of inflatable thin-walled structures for impact absorption. Finally, the last part introduces the concept of adaptive inflatable barrier and briefly presents three simple strategies of pressure control. Both the performed basic experiment and the conducted numerical simulations show the advantageous influence of compressed gas and prove the feasibility of using inflatable thin-walled structures for impact absorption.

Słowa kluczowe:

thin-walled structures, inflatable structures, crashworthiness

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Holnicki-Szulc J.-IPPT PAN
20p.
7.Holnicki-Szulc J., Graczykowski C., Mikułowski G., Mróz A., Pawłowski P., Wiszowaty R., Adaptive Impact Absorption - the Concept and Potential Applications, INTERNATIONAL JOURNAL OF PROTECTIVE STRUCTURES, ISSN: 2041-4196, DOI: 10.1260/2041-4196.6.2.357, Vol.6, No.2, pp.357-377, 2015

Streszczenie:

Adaptive Impact Absorption focuses on adaptation of energy absorbing structures to actual dynamic loading by using system of sensors detecting and identifying impact in advance and embedded semi-active dissipaters with controllable mechanical properties. Application of such devices allows to modify dynamic characteristics of the structure during the period of impact and to precisely control the process of energy dissipation. The paper presents an overview of research conducted at the Department of Intelligent Technologies of the Institute of Fundamental Technological Research dedicated to design and applications of various systems of Adaptive Impact Absorption. Wide range of presented examples covers adaptive hydraulic and pneumatic landing gears, skeletal systems equipped with controllable elements and detachable joints as well as adaptive inflatable structures.

Słowa kluczowe:

adaptive impact absorption, safety engineering, smart structures, optimal control

Afiliacje autorów:

Holnicki-Szulc J.-IPPT PAN
Graczykowski C.-IPPT PAN
Mikułowski G.-IPPT PAN
Mróz A.-IPPT PAN
Pawłowski P.-IPPT PAN
Wiszowaty R.-IPPT PAN
8.Sekuła K., Graczykowski C., Holnicki-Szulc J., On-line impact load identification, SHOCK AND VIBRATION, ISSN: 1070-9622, DOI: 10.3233/SAV-2012-0732, Vol.20, No.1, pp.123-141, 2013

Streszczenie:

The so-called Adaptive Impact Absorption (AIA) is a research area of safety engineering devoted to problems of shock absorption in various unpredictable scenarios of collisions. It makes use of smart technologies (systems equipped with sensors, controllable dissipaters and specialised tools for signal processing). Examples of engineering applications for AIA systems are protective road barriers, automotive bumpers or adaptive landing gears. One of the most challenging problems for AIA systems is on-line identification of impact loads, which is crucial for introducing the optimum real-time strategy of adaptive impact absorption. This paper presents the concept of an impactometer and develops the methodology able to perform real-time impact load identification. Considered dynamic excitation is generated by a mass M1 impacting with initial velocity V0. An analytical formulation of the problem, supported with numerical simulations and experimental verifications is presented. Two identification algorithms based on measured response of the impacted structure are proposed and discussed. Finally, a concept of the AIA device utilizing the idea of impactometer is briefly presented.

Słowa kluczowe:

Impact load identification, Adaptive Impact Absorption, adaptive structures, real-time systems, impact tests

Afiliacje autorów:

Sekuła K.-IPPT PAN
Graczykowski C.-IPPT PAN
Holnicki-Szulc J.-IPPT PAN
15p.
9.Graczykowski C., Lewiński T., Michell cantilevers constructed within a half strip. Tabulation of selected benchmark results, STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION, ISSN: 1615-147X, Vol.42, No.6, pp.869-877, 2010

Streszczenie:

The paper delivers the benchmark results for the Michell cantilevers constructed within a half strip, for selected values of the σT /σC ratio, σT , σC being the admissible stresses in tension and compression, respectively.

Słowa kluczowe:

Michell structures, Minimum weight design, Topology optimization, Trusses

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Lewiński T.-other affiliation
32p.
10.Graczykowski C., Holnicki-Szulc J., Protecting offshore wind turbines against ship impacts by means of Adaptive inflatable Structures, SHOCK AND VIBRATION, ISSN: 1070-9622, DOI: 10.3233/SAV-2009-0473, Vol.16, No.4, pp.335-353, 2009

Streszczenie:

Collisions with small service ships are serious danger for offshore wind turbines. Installing torus-shaped adaptive inflatable structure that surrounds a wind turbine tower at water level is one method of effective protection. Proposed pneumatic structure contains several separate air chambers equipped with devices for fast inflation and pressure release. The system can be adapted to various impact scenarios by adjusting the level of initial pressure in each chamber and by controlling the release of compressed air during collision. The paper presents finite element simulation of ship collision with wind turbine tower protected by pneumatic structure, conducted using ABAQUS software. Introduced methods of pressure adjustment are aimed at mitigating tower and ship response. The performed feasibility study proves that inflatable structure can effectively protect the wind turbine tower and the ship against serious damage.

Słowa kluczowe:

Adaptive inflatable structures, pneumatic structures, adaptive impact absorption, flow control, offshore structures, ship collisions

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Holnicki-Szulc J.-IPPT PAN
20p.
11.Holnicki-Szulc J., Graczykowski C., Mikułowski G., Mróz A., Pawłowski P.K., Smart technologies for adaptive impact absorption, SOLID STATE PHENOMENA, ISSN: 1012-0394, DOI: 10.4028/www.scientific.net/SSP.154.187, Vol.154, pp.187-194, 2009

Streszczenie:

The article presents a review of recent research carried out in the Department of Intelligent Technologies of Institute of Fundamental Technological Research, dedicated to application of systems for adaptive impact absorption to adaptive aircraft landing gears, novel concept of protective MFM structures, flow-control based airbags, maritime applications of inflatable structures, and development of adaptive wind turbine blade – hub connections.

Słowa kluczowe:

Adaptive Impact Absorption, Adaptive Structure, Optimal Control

Afiliacje autorów:

Holnicki-Szulc J.-IPPT PAN
Graczykowski C.-IPPT PAN
Mikułowski G.-IPPT PAN
Mróz A.-IPPT PAN
Pawłowski P.K.-IPPT PAN
20p.
12.Graczykowski C., Mikułowski G., Pawłowski P.K., Koncepcja absorbera pneumatycznego do zastosowania w podwoziach aparatów latających z wykorzystaniem układu rozpoznania energii uderzenia, JOURNAL OF AERONAUTICA INTEGRA, ISSN: 1896-8856, Vol.1, No.5, pp.25-31, 2009

Streszczenie:

Podwozia lotnicze są traktowane przez konstruktorów samolotów jako elementy konieczne, ale z wielu względów mające negatywny wpływ na projekt. Z punktu widzenia aerodynamiki podwozia w trakcie lotu, stawiają dodatkowy opór aerodynamiczny (mniejszy w przypadku podwozi chowanych), a z punktu widzenia możliwości przewożenia ładunków, pochłaniają część masy startowej samolotu, która mogłaby być wykorzystana na transport towarów lub pasażerów. Biorąc pod uwagę takie uwarunkowania, idealne podwozie lotnicze powinno ważyć jak najmniej i zajmować minimalną ilość miejsca.
Obecnie najpopularniejszym rodzajem podwozia stosowanego w lotnictwie jest typ olejowo-gazowy, który charakteryzuje się najkorzystniejszym stosunkiem sprawności do wagi. Sprawność obecnie stosowanych podwozi lotniczych dochodzi do 80%. Aczkolwiek jest to wartość, która jest uzyskiwana dla jednego predefiniowanego przypadku lądowania z określoną energią uderzenia samolotu o pas startowy. Praktyka pokazuje, że w rzeczywistości zmienność warunków lądowania jest dużo większa niż zakres, na jaki można zaprojektować klasyczne podwozie pasywne. Najczęściej energia uderzenia przy lądowaniu jest znacząco mniejsza od tej, jaką konstruktorzy zakładają do obliczeń w procesie projektowania.
Dwa przedstawione problemy w projektowaniu podwozi lotniczych mogą zostać rozwiązane dzięki koncepcji nowego podwozia gazowego przedstawionego w tym artykule. Po pierwsze, dzięki zastosowaniu technologii inteligentnych i wykorzystaniu materiału funkcjonalnego stało się możliwe zaprojektowanie amortyzatorów czysto gazowych w podwoziach do aparatów latających, dzięki czemu możliwe jest wyeliminowanie oleju hydraulicznego o znacznie większej gęstości od gazu i efektywne obniżenie ciężaru podwozia samolotu. Po drugie dzięki wprowadzeniu inteligentnego sterowania przepływem gazu w amortyzatorze, stała się możliwa adaptacja rzeczywistych charakterystyk pracy amortyzatora do aktualnej wartości energii uderzenia samolotu o pas startowy.
Artykuł przedstawia wstępną fazę badań koncepcyjnych nad gazowym absorberem uderzeń przeznaczonym od zastosowania w podwoziu aparatu latającego, sterowanym przy pomocy zaworu piezoelektrycznego. W trakcie badań wykonano serię prób na modelu numerycznym, która została zweryfikowana przy pomocy badań eksperymentalnych, do których zaprojektowano i zrealizowano sterowanie w pętli zamkniętej dla szybkiego zaworu piezo elektrycznego zintegrowanego z absorberem gazowym.

Słowa kluczowe:

podwozia lotnicze, podwozie adaptacyjne, adaptacyjna dyssypacja energii

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Mikułowski G.-IPPT PAN
Pawłowski P.K.-IPPT PAN
2p.
13.Graczykowski C., Lewiński T., Michell cantilevers constructed within trapezoidal domains - Part III: Force fields, STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION, ISSN: 1615-147X, Vol.33, No.1, pp.24-27, 2007

Streszczenie:

This paper complements the analysis of geometric properties of the Hencky nets within the Michell cantilevers constructed in the trapezoidal domains by providing the analytical formulae for the force fields. The force field analysis introduces a new division of the cantilever domain and enables an alternative method for computing the optimal weights.

Słowa kluczowe:

Michell cantilevers, layout optimization, minimum weight design

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Lewiński T.-other affiliation
14.Graczykowski C., Lewiński T., Michell cantilevers constructed within trapezoidal domains - Part IV: Complete exact solutions of selected optimal designs and their approximations by trusses of finite number of joints, STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION, ISSN: 1615-147X, Vol.33, No.2, pp.113-129, 2007

Streszczenie:

The paper concerns the Michell-like cantilevers transmitting a point load to a straight segment of a support. The feasible domain is of trapezoidal infinite shape, as in the previous parts of the paper. The ratio of allowable stresses in tension and compression is arbitrary, not necessarily equal to 1. The present, last part of the paper includes detailed geometric and static analyses of the optimal cantilevers for various admissible data, thus providing new benchmarks of topology optimization. All results are found by using analytical methods developed in the previous parts of the paper. Particular attention is put on the force field distribution within the fibrous domains. These force fields turn out to be defined in certain subdomains forming a static division. The volumes of the optimal cantilevers are computed in two manners: by direct integration of the density of fibres and summing it up with the volume of the reinforcing bars of finite cross sections, and by using the kinematic formula of Michell according to which the volume is proportional to the virtual work. The examples analysed prove that both approaches lead to identical results of the volumes, thus showing that the possible duality gaps vanish. The analytical solutions are verified by considering appropriately chosen sequences of trusses of finite number of joints converging to the exact Michell cantilevers.

Słowa kluczowe:

Michell cantilevers, layout optimization, minimum weight design

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Lewiński T.-other affiliation
15.Graczykowski C., Heinonen J., Feasibility study of adaptive inflatable structures for protecting wind turbines, Journal of Structural Mechanics, ISSN: 0783-6104, Vol.40, No.2, pp.7-23, 2007
16.Graczykowski C., Lewiński T., Michell cantilevers constructed within trapezoidal domains - Part I: Geometry of Hencky nets, STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION, ISSN: 1615-147X, Vol.32, pp.347-368, 2006

Streszczenie:

The present paper is the first part of the four-part work on Michell cantilevers transmitting a given point load to a given segment of a straight-line support, the feasible domain being a part of the half-plane contained between two fixed half-lines. The axial stress sigma in the optimal cantilevers is assumed to be bounded by −sigma_C=< sigma<=sigma_T, where sigma_C and sigma_T represent the allowable compressive and tensile stresses, respectively. The work provides generalization of the results of the article of Lewinski et al. (Int J Mech Sci 36:375–398, 1994a) to the case of sigma_T unequal sigma_C. The present, first part of the work concerns the analytical formation of the Hencky nets or the lines of fibres filling up the interior of the optimal cantilevers corresponding to an arbitrary position of the point of application of the given concentrated force.

Słowa kluczowe:

Michell cantilevers, layout optimization, minimum weight design

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Lewiński T.-other affiliation
17.Graczykowski C., Lewiński T., Michell cantilevers constructed within trapezoidal domains - Part II: Virtual displacement fields, STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION, ISSN: 1615-147X, Vol.32, pp.463-471, 2006

Streszczenie:

The present second part of the paper deals with the virtual displacement fields associated with the optimality conditions epsilon_1=1, epsilon_2 = -k, k=sigma_T/sigma_c, where sigma_T and sigma_C represent the allowable values of the tensile and compressive stress, respectively. The displacement fields vanish along a straight segment of a line support and are constructed within an infinite domain bounded by two half-lines. The displacement fields are provided by the integral formulae involving the Lamé fields found in part I of this paper. All the results are expressed in terms of Lommel-like functions. These results make it possible to determine the volumes of the optimal cantilevers designs within the feasible domain considered. Computation of the volumes along with analyses of concrete cantilevers will be the subject of part IV of the present paper.

Słowa kluczowe:

Michell cantilevers, layout optimization, minimum weight design

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Lewiński T.-other affiliation
18.Graczykowski C., Lewiński T., The lightest plane structures of a bounded stress level transmitting a point load to a circular, CONTROL AND CYBERNETICS, ISSN: 0324-8569, Vol.34, No.1, pp.227-253, 2005

Streszczenie:

The paper refers to the problem of Michell (1904) of finding the lightest fully stressed structures, composed of possibly infinite number of members, trasmitting a given load to a support forming a circle. The point load can be located within or outside the circle. The known analysis by Hemp (1973) is enhanced here by disclosing the explicit formulae for the weights of the ribs and the interior (fibrous domain). The optimal weight can be found by two manners: by applying the primal integral formula involving the density of the reinforcement or by computing the work of the load on the adjoint displacement. One of the aims of the paper is to show that both these formulae are equivalent. This identity is essential since in the case of point loads the equivalence of the primal and dual formulations has not been proved till now. The analytically found layouts are confirmed by analysis of trusses (of finite number of joints) approximating the exact Michell-like solutions.

Słowa kluczowe:

Michell cantilevers, layout optimization, minimum weight design

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Lewiński T.-other affiliation

Lista ostatnich monografii
1.
321
Graczykowski C., Heinonen J., Adaptive Inflatable Structures for protecting wind turbines against ship collisions, VTT Working Papers 59, pp.1-127, 2006
Lista rozdziałów w ostatnich monografiach
1.
417
Chikahiro Y., Ario I., Nakazawa M., Ono S., Holnicki-Szulc J., Pawłowski P., Graczykowski C., Mobile and Rapidly Assembled Structures IV, rozdział: An Experimental Study On The Design Method Of A Real-sized Mobile Bridge For A Moving Vehicle, N. De Temmerman,Vrije, C.A. Brebbia, WITPress, pp.93-106, 2014
2.
364
Graczykowski C., Knor G., Kołakowski P., Mikułowski G., Orłowska A., Pawłowski P., Skłodowski M., Świercz A., Wiszowaty R., Zieliński T.G., Monitorowanie obciążeń i stanu technicznego konstrukcji mostowych, rozdział: Wybrane zagadnienia monitorowania, IPPT Reports on Fundamental Technological Research, pp.189-236, 2014
3.
365
Wiszowaty R., Biczyk J., Graczykowski C., Mikułowski G., New Trends in Smart Technologies, rozdział: Method of impact energy dissipation by the use of the pneumatic impact absorber with a piezo-valve, Fraunhofer Verlag, pp.223-230, 2013
4.
196
Pawłowski P.K., Mikułowski G., Graczykowski C., Ostrowski M., Jankowski Ł., Holnicki-Szulc J., Smart technologies for safety engineering, rozdział: Adaptive impact absorption, Wiley, Holnicki-Szulc J. (Ed.), pp.153-213, 2008

Prace konferencyjne
1.Chikahiro Y., Ario I., Pawlowski P., Graczykowski C., Nakazawa M., Holnicki-Szulc J., Ono S., Dynamics of the scissors-type Mobile Bridge, EURODYN 2017, X International Conference on Structural Dynamics, 2017-09-10/09-13, Rome (IT), DOI: 10.1016/j.proeng.2017.09.339, No.199, pp.2919-2924, 2017

Streszczenie:

We have experienced many times a phenomenon in which a bridge is washed away due to a typhoon, heavy rain in the rainy season, localized torrential rain, tsunami, and other flood disasters, or in which a bridge is damaged by an earthquake or a tremor. There is accordingly increasing demand for new technology and science to restore bridges that have been washed away or damaged. The paper presents a new type of emergency bridge, called Mobile Bridge™(MB), which can be quickly constructed in case of damages after a natural disaster. The concept of the bridge is based on the application of scissor-type mechanism, which provides its rapid deployment. Up to now several experimental MBs of different size were constructed and tested. The presented research reviews fundamental numerical and experimental results for the MB version 4.0 (MB4.0). Experimental testing included strain and acceleration measurements in free and forced loading conditions. From these results, it was possible to estimate basic dynamic characteristics of the bridge. Besides, in order to provide a basis for development of new construction methods for structural reinforcement and suppression of vibrations, various numerical analyses were conducted. The conducted research allows for a better and safer design of the movable and foldable full-scale bridge, the MB.

Słowa kluczowe:

deployable bridge, scissors-type bridge, emergency bridge, light-weight structure, temporary bridge

Afiliacje autorów:

Chikahiro Y.-Shinshu University (JP)
Ario I.-Hiroshima University (JP)
Pawlowski P.-IPPT PAN
Graczykowski C.-IPPT PAN
Nakazawa M.-Tohoku Gakuin University (JP)
Holnicki-Szulc J.-IPPT PAN
Ono S.-Japan Construction Method and Machinery Research Institute (JP)
2.Graczykowski C., Pawłowski P., Mathematical Modelling of Adaptive Skeletal Structures for Impact Absorption and Vibration Damping, EURODYN 2017, X International Conference on Structural Dynamics, 2017-09-10/09-13, Rome (IT), DOI: 10.1016/j.proeng.2017.09.093, No.199, pp.1671-1676, 2017

Streszczenie:

The paper describes mathematical modelling of adaptive skeletal structures, which are equipped with semi-active dissipaters based on smart fluids or fast-operating valves and utilize the paradigm of real-time adaptation to external loading. The proposed approach is based on three subsequent stages: i) exact thermodynamic modelling of a single semi-active dissipater with the use of mass, momentum and energy conservation laws, ii) global description of the entire skeletal structure considered as an assembly of semi-active dissipaters in certain geometrical configuration, iii) real-time control of the fluid flow inside semi-active dissipaters providing instantaneous adaptability to actual dynamic loading. This methodology enables accurate representation of mechanical characteristics of the skeletal structure and reliable analysis of its adaptation capabilities.

Słowa kluczowe:

adaptive structures, skeletal structures, impact absorption, vibration damping

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Pawłowski P.-IPPT PAN
3.Chikahiro Y., Ario I., Adachi K., Shimizu S., Pawłowski P., Graczykowski C., Holnicki-Szulc J., FUNDAMENTAL STUDY ON DYNAMIC PROPERTY OF DEPLOYABLE EMERGENCY BRIDGE USING SCISSORS MECHANISM, Footbridge Berlin 2017, 6th International Footbridge Conference, 2017-09-06/09-08, TU Berlin (DE), DOI: 10.24904/footbridge2017.09352, pp.1-6, 2017

Streszczenie:

The paper presents a new type of emergency bridge, which can be quickly constructed in case of damages
after a natural disaster. The concept of the bridge is based on the application of scissor-type mechanism,
which provides its rapid deployment. In case of deployable structures apart from static analysis of different
configurations of expansion, it is very important to investigate the dynamic behavior of the system. High compliance and flexibility of the scissors-type bridge may influence user's comfort and safety in case of heavy dynamic loads such as human induced impacts, wind gusts or earthquakes. Up to now, the authors constructed several types of the experimental MBs. The presented research reviews fundamental numerical and experimental results for the Mobile Bridge 4.0. Experimental testing included strain and acceleration measurements in free and forced loading conditions. From these results, it was possible to estimate basic mechanics characteristics, that is statics and dynamic property, of the bridge. The conducted research allows for a better and safer design of the structure of the Mobile Bridge.

Słowa kluczowe:

Deployable Bridge; Scissors-type bridge; Emergency Bridge; Dynamic property; Natural frequency; Acceleration measurement

Afiliacje autorów:

Chikahiro Y.-Shinshu University (JP)
Ario I.-Hiroshima University (JP)
Adachi K.-Hiroshima University (JP)
Shimizu S.-Shinshu University (JP)
Pawłowski P.-other affiliation
Graczykowski C.-other affiliation
Holnicki-Szulc J.-IPPT PAN
4.Marijnissen M.J., Graczykowski C., Rojek J., Two-stage method for the simulation of the comminution process in a high-speed beater mill, MEC-2017, MINERAL ENGINEERING CONFERENCE, 2017-09-20/09-23, Wisła (PL), DOI: 10.1051/e3sconf/20171801011, No.18, pp.1-7, 2017

Streszczenie:

The paper presents a two-stage simplified method for the simulation of comminution process which takes place in a beater mill. The first stage of the proposed method is a simulation of the flow of gas and ore particles through a mill based on a two-phase continuous-discrete model. It allows to capture the interaction between the fluid flow and embedded particles, to determine trajectories of their motion and average velocities and frequencies of their collisions against the flywheel and the mill’s walls. The second stage of the proposed method is a discrete element method simulation of the process of comminution of a single ore particle. It allows to determine the size distribution of created smaller particles in terms of normal velocity and angle of impact and to estimate the global efficiency of the comminution process. The proposed simulation methodology is applied for the verification of the innovative concept of the pplication of high–speed beater mill for the comminution of the copper ore.

Afiliacje autorów:

Marijnissen M.J.-IPPT PAN
Graczykowski C.-IPPT PAN
Rojek J.-IPPT PAN
5.Faraj R., Graczykowski C., Holnicki-Szulc J., Knap L., Seńko J., Adaptable pneumatic shock-absorber, SMART 2017, 8th Conference on Smart Structures and Materials, 2017-06-05/06-08, Madrid (ES), pp.1-8, 2017

Streszczenie:

Pneumatic dampers are still an attractive subject of research in both modelling and experimental testing. Progress in the field of sensors and actuators allows to construct more and more efficient absorbers and dampers based on active or semi-active control algorithms. However, passive and semi-passive solutions are also developed because of their lower costs and simplicity. This paper presents adaptable pneumatic shock-absorber that allows to obtain optimal impact absorption and energy dissipation by a single reconfiguration performed at the beginning of the process. The absorber is composed of two cylinders including at least one narrow rectangular slot and adequate number of outflow vents precisely shaped for certain impact scenarios. During operation of the device the air is released through overlapping slots and selected vents, which provides constant value of the generated force. As a result, the shock-absorber works as a passive device but provides minimal value of the reaction force in similar manner as semi-active system equipped with fully controllable mechanical valve. The paper presents the results of numerical simulations of adaptable shock-absorber operation and attempts of demonstrator construction aimed at conducting experimental verification of the concept.

Słowa kluczowe:

Adaptable, Semi-passive, Impact Absorption, Pneumatic Shock-absorber

Afiliacje autorów:

Faraj R.-IPPT PAN
Graczykowski C.-IPPT PAN
Holnicki-Szulc J.-IPPT PAN
Knap L.-Warsaw University of Technology (PL)
Seńko J.-Warsaw University of Technology (PL)
6.Popławski B., Graczykowski C., Jankowski Ł., Controllable Truss-Frame Nodes in Semi-Active Damping of Vibrations, Advances in Science and Technology, ISSN: 1662-0356, DOI: 10.4028/www.scientific.net/AST.101.89, Vol.101, pp.89-94, 2017

Streszczenie:

In recent years, vibration damping strategies based on semi-active management of strain energy have attracted a large interest and were proven highly effective. However, most of published research considers simple one degree of freedom systems or study the same basic example (the first vibration mode of a cantilever beam) with the same control strategy. This contribution focuses on truss-frame nodes with controllable moment-bearing ability. It proposes and tests an approach that allows the control strategy to be extended to more complex structures and vibration patterns.

Słowa kluczowe:

adaptive impact absorption, smart structures, semi-active control, safety engineering

Afiliacje autorów:

Popławski B.-IPPT PAN
Graczykowski C.-IPPT PAN
Jankowski Ł.-IPPT PAN
7.Jankowski Ł., Graczykowski C., Pawłowski P., Mikułowski G., Ostrowski M., Popławski B., Faraj R., Suwała G., Holnicki-Szulc J., Adaptive Self-Protection against Shock and Vibration, Advances in Science and Technology, ISSN: 1662-0356, DOI: 10.4028/www.scientific.net/AST.101.133, Vol.101, pp.133-142, 2017

Streszczenie:

This contribution reviews the challenges in adaptive self-protection of structures. A proper semi-active control strategy can significantly increase structural ability to absorb impact-type loads and damp the resulting vibrations. Discussed systems constitute a new class of smart structures capable of a real-time identification of loads and vibration patterns, followed by a low-cost optimum absorption of the energy by structural adaptation. Given the always surging quest for safety, such systems have a great potential for practical applications (in landing gears, road barriers, space structures, etc.). Compared to passive systems, their better performance can be attributed to the paradigm of self-adaptivity, which is ubiquitous in nature, but still sparsely applied in structural engineering. Being in the early stages of development, their ultimate success depends on a concerted effort in facing a number of challenges. This contribution discusses some of the important problems, including these of a conceptual, technological, methodological and software engineering nature.

Słowa kluczowe:

adaptive impact absorption, smart structures, semi-active control, safety engineering

Afiliacje autorów:

Jankowski Ł.-IPPT PAN
Graczykowski C.-IPPT PAN
Pawłowski P.-IPPT PAN
Mikułowski G.-IPPT PAN
Ostrowski M.-IPPT PAN
Popławski B.-IPPT PAN
Faraj R.-IPPT PAN
Suwała G.-IPPT PAN
Holnicki-Szulc J.-IPPT PAN
8.Rojek J., Graczykowski C., Marijnissen M.J., Szolc T., Marczewska I., Możliwości wykorzystania dyskretnych metod modelowania do symulacji procesów mechanicznego urabiania i przeróbki rud metali, ICNOP 2015, XI Międzynarodowa Konferencja Przeróbki Rud Metali Nieżelaznych, 2015-05-27/05-29, Trzebieszowice (PL), pp.60-67, 2015

Streszczenie:

Modelowanie i symulacje numeryczne są obecnie nieodłączną częścią projektowania i optymalizacji różnorodnych procesów technologicznych. Zastosowanie metod numerycznych w projektowaniu procesów mechanicznego urabiania i przeróbki rud metali jest w dalszym ciągu stosunkowo niewielkie. Procesy odspajania kawałków skały od calizny i ich rozdrobnienia z zastosowaniem różnego rodzaju maszyn, wiążą się silnie nieciągłymi zjawiskami zniszczenia materiału i są bardzo trudne do modelowania za pomocą standardowych metod numerycznych, takich jak metoda elementów skończonych, opartych na ciągłym sformułowaniu zagadnienia mechaniki ciała stałego. Duże możliwości w zastosowaniu do tych procesów ma intensywnie rozwijana w ostatnich latach metoda elementów dyskretnych, w której materiał jest reprezentowany przez liczny zbiór ziaren, oddziałujących między sobą poprzez siły kontaktu. Model ten w sposób naturalny uwzględnia materiał rozdrobniony. Uwzględnienie wiązań kohezyjnych między ziarnami oraz możliwości ich zrywania umożliwia modelowanie inicjacji i propagacji pęknięć w materiale. W niniejszej pracy zostaną przedstawione możliwości wykorzystania metody elementów dyskretnych do symulacji urabiania skał za pomocą noży stożkowych i dysków oraz do symulacji zachowania się materiału w młynie. Sprzężenie metody elementów dyskretnych z modelem przepływu płynu umożliwi modelowanie zawiesiny pyłowej rozdrabnianego materiału.

Słowa kluczowe:

modelowanie dyskretne, mechaniczne urabianie, rudy metali

Afiliacje autorów:

Rojek J.-IPPT PAN
Graczykowski C.-IPPT PAN
Marijnissen M.J.-IPPT PAN
Szolc T.-IPPT PAN
Marczewska I.-IPPT PAN
9.Holnicki-Szulc J., Sekuła K., Graczykowski C., On-line Impact Load Identification for Adaptive Impact Absorption, 6th Conference on Protection of Structures Against Hazards, 2014-10-16/10-17, Tianjin (CN), pp.35-44, 2014

Streszczenie:

The so-called Adaptive Impact Absorption (AIA) is a research area of safety engineering devoted to problems of shock absorption in various unpredictable scenarios of collisions. It makes use of smart technologies including systems equipped with sensors, controllable dissipaters and specialized tools for signal processing. One of the most challenging problems for AIA systems is on-line identification of impact lo ads, which is crucial for introducing optimum real-time strategy of adaptive impact absorption. This paper presents development of methodology which enables real-time impact load identification. In considered problem a dynamic excitation is generated by a mass M 1 impacting with initial velocity V 0 . An analytical formulation of the problem, corresponding numerical simulations and experimental tests are presented. Two identification algorithms based on measured response of the impacted structure are proposed and thoroughly discussed. Finally, a concept of the AIA device utilizing the idea of detecting device (the so called “impactometer”) is briefly described.

Słowa kluczowe:

Impact Load Identification, Adaptive Impact Absorption, Real-time Systems

Afiliacje autorów:

Holnicki-Szulc J.-IPPT PAN
Sekuła K.-other affiliation
Graczykowski C.-IPPT PAN
10.Graczykowski C., Pawłowski P., Physical Modeling of Magnetorheological Damper, 6WCSCM, 6th World Conference on Structural Control and Monitoring, 2014-07-15/07-17, Barcelona (ES), pp.1-10, 2014

Streszczenie:

The paper describes enhanced physical model of MR damper which takes into account the effects of blocking the flow between the chambers in case of low pressure difference and the compressibility of the fluid enclosed in each chamber. Combination of both effects is considered as the reason of gene ration of the characteristic shapes of force-velocity hysteresis loops. The subsequent sections of the paper contain derivation of the thermodynamic equations governing response of the damper and their implementation for two constitutive models of the magnetorheological fluid. Successful qualitative comparison against the experiment proves the correctness of applied assumptions and the relevance of the proposed model.

Słowa kluczowe:

magnetorgeological fluids, MRF dampers, physical-based modeling

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Pawłowski P.-IPPT PAN
11.Graczykowski C., Orłowska A., Venkat R.S., The concept of smart prestressed composites. Numerical modelling and experimental evaluation, SMART2013, 6th ECCOMAS Thematic Conference on Smart Structures and Materials, 2013-09-03/09-06, Turyn (IT), pp.1-22, 2013

Streszczenie:

The paper introduces the concept of prestressing selected layers of laminated composite in order to increase its stiffness and improve its overall mechanical response. Both analytical and numerical models of prestressed composites are proposed and utilized to optimize applied prestressing forces. Further, dedicated laboratory stand and developed methodology of experimental evaluation are described. The final part of the paper briefly discusses prospective applications of prestressed composites.

Słowa kluczowe:

prestressed structures, laminated composites, prestressed reinforced composites

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Orłowska A.-IPPT PAN
Venkat R.S.-Fraunhofer Institute for Nondestructive Testing (DE)
12.Pawłowski P., Ostrowski M., Graczykowski C., High performance valves for adaptive inflatable structures with flow driven control, SMART2013, 6th ECCOMAS Thematic Conference on Smart Structures and Materials, 2013-09-03/09-06, Turyn (IT), pp.1-10, 2013

Streszczenie:

The paper presents a concept of new adaptive valve s, which can be applied in the Adaptive Inflatable Structures for impact absorption - high-performance membrane and bistable snap-through valve. The main idea behind those concepts is to employ fluid flow in order to assist actuation of the system.

Słowa kluczowe:

adaptive impact absorption, inflatable structures, high performance valves

Afiliacje autorów:

Pawłowski P.-IPPT PAN
Ostrowski M.-IPPT PAN
Graczykowski C.-IPPT PAN
13.Pawłowski P., Graczykowski C., Holnicki-Szulc J., Ario I., Smart, deployable skeletal structures for safety engineering, SMART2013, 6th ECCOMAS Thematic Conference on Smart Structures and Materials, 2013-09-03/09-06, Turyn (IT), pp.1-10, 2013

Streszczenie:

This contribution presents the concept of smart, deployable skeletal structures along with existing and prospective applications. The first part introduce s the concept of multi-folding, which is the basis for the design of all smart deployable skeletal structures. In the second part three diverse innovative applications are described: deployable mobile bridge, adaptive impact absorber and controllable valve.

Słowa kluczowe:

smart skeletal structures, adaptive impact absorption, safety engineering

Afiliacje autorów:

Pawłowski P.-IPPT PAN
Graczykowski C.-IPPT PAN
Holnicki-Szulc J.-IPPT PAN
Ario I.-Hiroshima University (JP)
14.Graczykowski C., Theoretical models and numerical methods for adaptive inflatable structures, Civil-Comp Proceedings, ISSN: 1759-3433, DOI: 10.4203/ccp.102.198, Vol.102, pp.1-26, 2013

Streszczenie:

The paper describes various approaches for mathematical modelling of adaptive inflatable structures (AIS) along with corresponding numerical methods . The introductory part presents a general idea of adaptive impact absorption (AIA) and the concept of inflatable structures equipped with controllable valves serving for internal pressure control. Application of AIS for adaptive absorption of the impact loading is briefly explained. The paper focuses on methods of modelling of inflatable structures , which are based on interaction between solid wall s and fluid enclosed inside. Modelling of the solid walls is based on rigid body dynamics or initial boundary value problem of solid mechanics. In turn, modelling of the fluid utilizes either classical equilibrium thermodynamics or Navier -Stokes equations. Consequently, f our possible combinations of the above approaches are distinguished, precisely analyzed and applied for modelling of different types of inflatable structures. Each model takes into account controllable valve s, which require introducing additional coupling between parameters defining the valve s and selected results of the analysis. Corresponding numerical methods include Runge - Kutta methods, finite volume method ( FVM ) applied for problem s with mo bile boundaries, classical finite element method ( FEM ) and finally FEM coupled with FVM. Proposed numerical methods and software tool s are utilized for simulation of adaptive pneumatic cylinders, adaptive pneumatic fenders and membrane valves.

Słowa kluczowe:

inflatable structures, impact absorption, fluid-structure interaction

Afiliacje autorów:

Graczykowski C.-IPPT PAN
15.Holnicki-Szulc J., Graczykowski C., Grzędziński J., Mikułowski G., Mróz A., Pawłowski P., Wiszowaty R., Adaptive Impact Absorption - the concept, simulations and potential applications, 4th International Conference on Protection of Structures Against Hazards, 2012-11-15/11-16, , pp.1-16, 2012

Streszczenie:

Adaptive Impact Absorption focuses on adaptation of energy absorbing structures to actual dynamic loading by using system of sensors detecting and identifying impact in advance and semi -active dissipaters with controllable mechanical properties which enable change of system dynamic characteristics in real time. The article present s a review of research conducted at the Department of Intelligent Technologies of the Institute of Fundamental Technological Research dedicated to applications of systems for Adaptive Impact Absorption. Wide range of presented examples covers pneumatic landing gears, bumpers for offshore towers, wind turbine blade-hub connections and d protective barriers for automotive applications.

Słowa kluczowe:

adaptive impact absorption, safety engineering, smart structures, optimal control

Afiliacje autorów:

Holnicki-Szulc J.-IPPT PAN
Graczykowski C.-IPPT PAN
Grzędziński J.-IPPT PAN
Mikułowski G.-IPPT PAN
Mróz A.-IPPT PAN
Pawłowski P.-IPPT PAN
Wiszowaty R.-IPPT PAN
16.Graczykowski C., Holnicki-Szulc J., Adaptive Fenders for Extreme Off-shore Docking Operations, EACS 2012, 5th European Conference on Structural Control, 2012-06-18/06-20, Genoa (IT), pp.1-8, 2012

Streszczenie:

Collisions with small service ships are serious dangers for offshore wind turbines. Installing of the adaptive torus-shaped pneumatic fender that surrounds wind turbine tower at water level constitutes on e method of effective protection against such events. Innovative pneumatic fender proposed in this paper contains several internal air-chambers equipped wit h fast inflators and high-performance valves allowing for control of gas migration and release. The system ca n be adapted to various impact scenarios by adjusting the level of initial pressure in each chamber and by controlling transfer of compressed gas during impact. The paper presents numerical simulations of ship collision against wind turbine tower protected by adaptive fender conducted by means of FEM-based software. Several control strategies aimed at mitigating tower and ship response are introduced. Performed feasibility study proves that inflatable structure can effectively protect the wind turbine tower and the ship against serious damages.

Słowa kluczowe:

Adaptive Inflatable Structures (AIS), pneumatic fenders, Adaptive Impact Absorption (AIA), offshore collisions, off-shore docking operations

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Holnicki-Szulc J.-IPPT PAN
17.Holnicki-Szulc J., Graczykowski C., Mikułowski G., Mróz A., Ostrowski M., Wiszowaty R., Adaptive impact absorption for safety engineering, 9th International Conference on Shock & Impact Loads on Structures, 2011-11-16/11-18, Fukuoka (JP), pp.373-385, 2011

Streszczenie:

Adaptive Impact Absorption focuses on active adaptation of energy absorbing structures to actual dynamic loading by using system of sensors detecting and identifying impact in advance and controllable semi-active dissipaters with high ability of adaptation. The article presents a review of research carried out in the Department of Intelligent Technologies of Institute of Fundamental Technological Research dedicated to applications of systems for adaptive impact absorption. Wide range of presented examples covers pneumatic landing gears, adaptive crashworthy structures, wind turbine blade-hub connections and flow control based airbags for maritime and aeronautical applications.

Słowa kluczowe:

smart structures, adaptive structures, Adaptive Impact Absorption, crashworthiness, safety engineering

Afiliacje autorów:

Holnicki-Szulc J.-IPPT PAN
Graczykowski C.-IPPT PAN
Mikułowski G.-IPPT PAN
Mróz A.-IPPT PAN
Ostrowski M.-IPPT PAN
Wiszowaty R.-IPPT PAN
18.Graczykowski C., Mikułowski G., Holnicki-Szulc J., Adaptive impact absorption – a benchmark and an example absorber, SMART2011, 5th ECCOMAS Thematic Conference on Smart Structures and Materials, 2011-07-06/07-08, Saarbrücken (DE), pp.663-668, 2011

Streszczenie:

This paper proposes a benchmark for conceptual devices dedicated to adaptive impact absorption (AIA) and protection against shock excitations. The problem of the exploitation impacts is present in a wide class of applications, and particularly where direction of the object’s movement is well-defined, for example: precise docking systems, rail car buffers or landing gear shock absorbers. In those applications the objective is to equalize the values of velocities of the bodies in order to minimize the deceleration peak. The proposed benchmark establishes a comparing procedure for materials or devices in the field of AIA in a simplified regime in order to improve the comparability of the solutions. A drop test device is proposed to be used for testing the proposed devices in the predefined experimental regime. Besides, an example of the adaptive absorber is presented.

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Mikułowski G.-IPPT PAN
Holnicki-Szulc J.-IPPT PAN
19.Graczykowski C., Sekuła K., Holnicki-Szulc J., Real-time identification of impact load parameters, SMART2011, 5th ECCOMAS Thematic Conference on Smart Structures and Materials, 2011-07-06/07-08, Saarbrücken (DE), pp.544-551, 2011
20.Wiszowaty R., Biczyk J., Graczykowski C., Mikułowski G., Method of impact energy dissipation by the use of the pneumatic impact absorber with a piezo-valve, SMART2011, 5th ECCOMAS Thematic Conference on Smart Structures and Materials, 2011-07-06/07-08, Saarbrücken (DE), pp.640-647, 2011

Słowa kluczowe:

Adaptive structures, Shock absorption, Impact energy absorption, Piezoelectric valve

Afiliacje autorów:

Wiszowaty R.-IPPT PAN
Biczyk J.-Adaptronica Sp. z o. o. (PL)
Graczykowski C.-IPPT PAN
Mikułowski G.-IPPT PAN
21.Mikułowski G., Pawłowski P., Graczykowski C., Wiszowaty R., Holnicki-Szulc J., On a pneumatic adaptive landing gear system for a small aerial vehicle, SMART 2009, 4th ECCOMAS Thematic Conference on Smart Structures and Materials, 2009-07-13/07-15, Porto (PT), pp.1-9, 2009

Streszczenie:

The class of ultra-light aircraft becomes more and more popular among the enthusiasts of aviation due to low formal requirements of getting the pilot license and low costs of the equipment. Therefore, the training of the pilots starts to be a large-scale task. One of the most difficult operation for the inexperienced pilots is touch-down and it often happens to strike the ground with a high sink speed. In consequence the training machines are endangered of fast structural damage. A potential solution would be to mount a system of adaptive landing gear for light aircraft with a capability of recognition of the actual landing impact and tuning the landing struts in order to conduct the smoothest landing operation possible. In the case of the ultra-light aircraft class the weight of the components is the crucial task and therefore the low-weight pneumatic system is proposed for these application.
The paper presents a concept of an adaptive landing system and adequate control strategy for a small aerial vehicle. The objective of the work was to develop a fully functional model of the landing system and experimental verification of it. The system is based on the new pneumatic impact absorbers actuated via piezo-stacks. The concept assumes designing of the system with the capability of adaptation to actual energy of impact scenario identified by a dedicated sensing system for impact energy recognition.
The designed control system was dedicated to process the data from the system of impact energy recognition in order to perform the optimal landing scenario. The objective of the control strategy was minimization of the structure’s deceleration peaks during the touchdown.
The presented results consist of numerical analysis of the adopted strategy of control and experimental verification of the concept on the dedicated experimental device. The results proved that the proposed method allowed minimization of the maximal deceleration level acting on the demonstrator.

Afiliacje autorów:

Mikułowski G.-IPPT PAN
Pawłowski P.-IPPT PAN
Graczykowski C.-IPPT PAN
Wiszowaty R.-IPPT PAN
Holnicki-Szulc J.-IPPT PAN

Abstrakty konferencyjne
1.Chikahiro Y., Ario I., Adachi K., Shimizu S., Zenzai S., Pawłowski P., Graczykowski C., Holnicki-Szulc J., FUNDAMENTAL STUDY ON DYNAMIC PROPERTY OF SCISSORING BRIDGE FOR DISASTER RELIEF, ENOC 2017, 9th European Nonlinear Dynamics Conference, 2017-06-25/06-30, Budapest (HU), pp.1-2, 2017

Streszczenie:

The world has seen many kinds of natural disasters, which have critically influenced the residents’ lives by causing damage to infrastructure. To realize rapid rescue efforts in an emergency situation,we propose a deployable emergency bridge, called Mobile Bridge TM [1], based on the theory of foldable structures[2]and the concept of Multi-Folding Microstructures (MFM)[3]. The current research presents the fundamental,numerical and experimental results obtained for the pedestrian and vehicle Mobile Bridges. In this paper, it is considered the localized linearization problem with the fixed an angle although this bridge contains a geometrical nonlinearity of scissors structure.Additionally, a seismic response analysis is conducted for the case where the Mobile Bridge is used in the disaster area as an emergency bridge. This allows for a better and safer structural design of the Mobile Bridge, which is patented in [4],[5].

Afiliacje autorów:

Chikahiro Y.-Shinshu University (JP)
Ario I.-Hiroshima University (JP)
Adachi K.-Hiroshima University (JP)
Shimizu S.-Shinshu University (JP)
Zenzai S.-Shinshu University (JP)
Pawłowski P.-IPPT PAN
Graczykowski C.-IPPT PAN
Holnicki-Szulc J.-IPPT PAN
2.Chikahiro Y., Ario I., Pawlowski P., Graczykowski C., Nakazawa M., Holnicki-Szulc J., Ono S., Dynamics of the scissors-type Mobile Bridge, EURODYN 2017, X International Conference on Structural Dynamics, 2017-09-10/09-13, Rome (IT), pp.199-199, 2017
3.Graczykowski C., Pawłowski P., Mathematical Modelling of Adaptive Skeletal Structures for Impact Absorption and Vibration Damping, EURODYN 2017, X International Conference on Structural Dynamics, 2017-09-10/09-13, Rome (IT), pp.123-123, 2017
4.Chikahiro Y., Ario I., Adachi K., Shimizu S., Pawłowski P., Graczykowski C., Holnicki-Szulc J., FUNDAMENTAL STUDY ON DYNAMIC PROPERTY OF DEPLOYABLE EMERGENCY BRIDGE USING SCISSORS MECHANISM, Footbridge Berlin 2017, 6th International Footbridge Conference, 2017-09-06/09-08, TU Berlin (DE), pp.1-6, 2017

Streszczenie:

The paper presents a new type of emergency bridge, which can be quickly constructed in case of damages
after a natural disaster. The concept of the bridge is based on the application of scissor-type mechanism,
which provides its rapid deployment. In case of deployable structures apart from static analysis of different
configurations of expansion, it is very important to investigate the dynamic behavior of the system. High compliance and flexibility of the scissors-type bridge may influence user's comfort and safety in case of heavy dynamic loads such as human induced impacts, wind gusts or earthquakes. Up to now, the authors constructed several types of the experimental MBs. The presented research reviews fundamental numerical and experimental results for the Mobile Bridge 4.0. Experimental testing included strain and acceleration measurements in free and forced loading conditions. From these results, it was possible to estimate basic mechanics characteristics, that is statics and dynamic property, of the bridge. The conducted research allows for a better and safer design of the structure of the Mobile Bridge.

Słowa kluczowe:

Deployable Bridge; Scissors-type bridge; Emergency Bridge; Dynamic property; Natural frequency; Acceleration measurement

Afiliacje autorów:

Chikahiro Y.-Shinshu University (JP)
Ario I.-Hiroshima University (JP)
Adachi K.-Hiroshima University (JP)
Shimizu S.-Shinshu University (JP)
Pawłowski P.-other affiliation
Graczykowski C.-other affiliation
Holnicki-Szulc J.-other affiliation
5.Faraj R., Graczykowski C., Holnicki-Szulc J., Investigations on adaptable and adaptive impact absorption, ICAST2017, The 28th International Conference on Adaptive Structures and Technologies, 2017-10-08/10-11, Kraków (PL), pp.1, 2017
6.Orłowska A., Graczykowski C., Gałęzia A., Manufacturing and properties of pre-stressed GFRP composites, MECHCOMP3, 3rd International Conference on Mechanics of Composites, 2017-07-04/07-07, School of Engineering and Architecture, University of Bologna, Italy (IT), pp.48-48, 2017

Streszczenie:

The concept of increasing strength capacity of structural elements by introducing preliminary stresses, counteracting the exploitation stresses, is known for years. Large number of applications of pre-stressed materials in civil engineering proves that proper compression of material can effectively increase the strength of structural elements. Because of the rapid development of composite materials, and growing demand for light materials with particularly high stiffness and strength properties, the pre-stressed FRP composites application in industry seems to be a question of time. This assumption is confirmed by increasing number of publications concerning the problem of mechanical characteristics for such materials.
This paper presents the results of preliminary research on the pre-stressing of the FRP composite structures, while the term pre-stress indicates initial tensile stress applied to the fibres embedded in selected layers of the composite material. Manufacturing process and shape forming possibilities as well as short-term static and dynamic behaviour of the pre-stressed composites are discussed. Presented results are achieved by the use of the experimental methods (three-point bending tests and Experimental Modal Analysis) and experimentally verified Finite Element Method model of pre-stressed structure.

Afiliacje autorów:

Orłowska A.-IPPT PAN
Graczykowski C.-IPPT PAN
Gałęzia A.-Warsaw University of Technology (PL)
7.Graczykowski C., Orłowska A., Modelling and design procedure of prestressed composite materials, MECHCOMP3, 3rd International Conference on Mechanics of Composites, 2017-07-04/07-07, School of Engineering and Architecture, University of Bologna, Italy (IT), pp.154-154, 2017

Streszczenie:

The paper introduces the concept of eccentrical prestressing of fiber reinforced polymer materials in order to improve their mechanical properties and global mechanical behaviour. Prestressing is here understood as application of the initial tensile stress to the fibres embedded in selected external layers of the composite material. The objective of prestressing is to increase stiffness of the composite and to obtain desired response to applied external loading. The main objective of this research work is to develop a comprehensive approach to analysis of prestressed composites, which includes analytical and numerical modelling of the static behaviour, optimal composite design, as well as, simulation of dynamic response. Initially, we derive simple and effective analytical model of prestressed composite based on models of individual prestressed plies and their homogenization. The analytical model is used to reveal beneficial influence of prestress on strain and stress distribution in particular plies and resulting increase of the composite stiffness. Further, three options for the FEM-based numerical modelling of prestressed composites are proposed and thoroughly compared with each other. Developed analytical and numerical models are used to propose methods of prestressed composite design in which optimization of prestressing forces is used to minimize required composite thickness or fiber volume fraction. Eventually, FEM simulations are applied to assess the influence of prestress force magnitude on natural frequencies and modal shapes of eccentrically prestressed composite beams of various fibre volume fraction. The final part of the paper summarizes the potential advantages of the prestressed composites and unveils their superiority in comparison to the standard ones. Potential applications of prestressed composite materials in civil engineering and aerospace industry are briefly discussed. In addition, challenges related to design and manufacturing of structures made of prestressed composite materials are presented.

Afiliacje autorów:

Graczykowski C.-IPPT PAN
Orłowska A.-IPPT PAN
8.Faraj R., Graczykowski C., Holnicki-Szulc J., Knap L., Seńko J., Adaptable pneumatic shock-absorber, SMART 2017, 8th Conference on Smart Structures and Materials, 2017-06-05/06-08, Madrid (ES), pp.1, 2017

Streszczenie:

Pneumatic dampers are still an attractive subject of research in both modelling and experimental testing. Progress in the field of sensors and actuators allows to construct more and more efficient absorbers and dampers based on active or semi-active control algorithms. However, passive and semi-passive solutions are also developed because of their lower costs and simplicity. This paper presents adaptable pneumatic shock-absorber that allows to obtain optimal impact absorption and energy dissipation by a single reconfiguration performed at the beginning of the process. The absorber is composed of two cylinders including at least one narrow rectangular slot and adequate number of outflow vents precisely shaped for certain impact scenarios. During operation of the device the air is released through overlapping slots and selected vents, which provides constant value of the generated force. As a result, the shock-absorber works as a passive device but provides minimal value of the reaction force in similar manner as semi-active system equipped with fully controllable mechanical valve. The paper presents the results of numerical simulations of adaptable shock-absorber operation and attempts of demonstrator construction aimed at conducting experimental verification of the concept.

Słowa kluczowe:

Adaptable, Semi-passive, Impact Absorption, Pneumatic Shock-absorber.

Afiliacje autorów:

Faraj R.-IPPT PAN
Graczykowski C.-IPPT PAN
Holnicki-Szulc J.-IPPT PAN
Knap L.-Warsaw University of Technology (PL)
Seńko J.-Warsaw University of Technology (PL)
9.Chikahiro Y., Ario I., Holnicki-Szulc J., Pawłowski P., Graczykowski C., A Study on Optimal Reinforcement of Scissor Type of Bridge with Additional Strut Members, ICCEE 2016, International Conference on Civil and Environmental Engineering, 2016-10-17/10-19, Hiroshima (JP), pp.1-2, 2016

Słowa kluczowe:

scissor type of bridge, emergency bridge, strut reinforcement, sectional optimization

Afiliacje autorów:

Chikahiro Y.-Shinshu University (JP)
Ario I.-Hiroshima University (JP)
Holnicki-Szulc J.-IPPT PAN
Pawłowski P.-IPPT PAN
Graczykowski C.-IPPT PAN
10.Pawłowski P., Graczykowski C., Ostrowski M., Sekuła K., Mróz A., Controllable high performance valves for improved crashworthiness of inflatable structures, PETER 2015, Annual International Workshop on Dynamic Behaviour of Structures and Materials, Interaction and Friction Across the Strain Rates, 2015-08-26/08-28, London (GB), pp.52-53, 2015

Słowa kluczowe:

adaptive inflathigh performance valves, adaptive inflatable structures

Afiliacje autorów:

Pawłowski P.-IPPT PAN
Graczykowski C.-IPPT PAN
Ostrowski M.-IPPT PAN
Sekuła K.-other affiliation
Mróz A.-IPPT PAN
11.Holnicki-Szulc J., Faraj R., Graczykowski C., Jankowski Ł., Mikułowski G., Mróz A., Ostrowski M., Pawłowski P., Wiszowaty R., Adaptive impact absorption - potential applications for safety engineering, SMART 2015, 7th ECCOMAS Thematic Conference on Smart Structures and Materials, 2015-06-03/06-05, Ponta Delgada (PT), pp.1-2, 2015

Słowa kluczowe:

Smart And Adaptive Structures, Adaptive Impact Absorption, Safety Engineering

Afiliacje autorów:

Holnicki-Szulc J.-IPPT PAN
Faraj R.-IPPT PAN
Graczykowski C.-IPPT PAN
Jankowski Ł.-IPPT PAN
Mikułowski G.-IPPT PAN
Mróz A.-IPPT PAN
Ostrowski M.-IPPT PAN
Pawłowski P.-IPPT PAN
Wiszowaty R.-IPPT PAN
12.Pawłowski P., Graczykowski C., Holnicki-Szulc J., Bistable Elements for Application in Controllable High Performance Valves, 6WCSCM, 6th World Conference on Structural Control and Monitoring, 2014-07-15/07-17, Barcelona (ES), pp.1, 2014

Słowa kluczowe:

high performance valve, bistable elements, snap-through, adaptive impact absorption

Afiliacje autorów:

Pawłowski P.-IPPT PAN
Graczykowski C.-IPPT PAN
Holnicki-Szulc J.-IPPT PAN
13.Chikahiro Y., Ario I., Nakazawa M., Ono S., Holnicki-Szulc J., Pawłowski P., Graczykowski C., Structural Analysis and Experimental Study for realsized MB Travelable Vehicles, ENOC 2014, 8th European Nonlinear Dynamics Conference, 2014-07-06/07-11, Wiedeń (AT), pp.1-2, 2014

Streszczenie:

Many natural disasters such as earthquakes, floods, torrential rains occur around the world, and we to undertake quick rescue actions. However, there are many recovery problems because of the occurrence of secondary disasters at each rescue worksite.So, from the previous study of optimal structures and control regulation of MFM[1]-[2], we propose a new type of foldable bridge with scissors structure called Mobile Bridge[3]. Applying scissors mechanism to bridge form, Mobile Bridge provides not only mobility but also good structural performance, because the whole bridge can be expand or fold quickly. In this paper, we discuss the vehicles passing test on the real scale Mobile Bridge in order to evaluate the design method and application limits.

Słowa kluczowe:

Mobile Bridge, deployable structures, temporary bridges, scissors-type structures

Afiliacje autorów:

Chikahiro Y.-Shinshu University (JP)
Ario I.-Hiroshima University (JP)
Nakazawa M.-Tohoku Gakuin University (JP)
Ono S.-Japan Construction Method and Machinery Research Institute (JP)
Holnicki-Szulc J.-IPPT PAN
Pawłowski P.-IPPT PAN
Graczykowski C.-IPPT PAN
14.Holnicki-Szulc J., Graczykowski C, Pawłowski P., Ario I., High Performance Valve for Adaptive Pneumatic Impact Absorbers, SolMech 2012, 38th Solid Mechanics Conference, 2012-08-27/08-31, Warszawa (PL), pp.1-2, 2012

Streszczenie:

Dissipation of the energy in mechanical systems is a vitally important engineering and scientific problem. Current stringent safety requirements enforce substantial change of methods of structural design and application of new solutions and technologies which ensure structural integrity.
Currently applied passive safety systems are typically not equipped with control devices. Their dynamic characteristics remains unaltered and thus it is well adjusted to a narrow range of actual loadings. In case of impact loading, it is highly advantageous to apply systems of Adaptive Impact Absorption (AIA), which are capable of fast change of the dynamic characteristics. Recent fast development of the material technologies and, in particular, development in the field of functional (smart) materials and electronic measurement and control systems had created new possibilities of practical applications of the AIA systems.
During the adaptation process the choice of optimal control strategy is followed by adjustment of the dynamic characteristics of adaptive elements of the absorber. These elements can entirely made of functional materials (as e.g. shape memory alloys) or, alternatively, they can be equipped with controllable devices, so-called structural fuses, which provide controlled response of the element. Depending on type of applied control, the changes of structural parameters occur only once (usually before impact) or they are controlled in real time during the impact process.
The systems of Adaptive Impact Absorption can be effectively used to increase the level of safety during the action of the impact loading. In particular, very promising results are obtained with the use of adaptive inflatable structures. However, the possibilities of their practical applications are limited due to the lack methods allowing for the efficient and fast control of the gas flow during impact.
The presented work focuses on the pneumatic adaptive impact absorbing system equipped with a novel, high performance valve, which utilizes bistable snap-through effect. Snap-through effects are mainly the subject of theoretical analysis and they do not find many practical engineering applications.

Słowa kluczowe:

smart structures, high performance valves, adaptive pneumatic systems, adaptive impact absorption

Afiliacje autorów:

Holnicki-Szulc J.-IPPT PAN
Graczykowski C-IPPT PAN
Pawłowski P.-IPPT PAN
Ario I.-Hiroshima University (JP)

Patenty
Numer/data zgłoszenia patentowego
Ogłoszenie o zgłoszeniu patentowym
Twórca / twórcy
Tytuł
Kraj i Nazwa uprawnionego z patentu
Numer patentu
Ogłoszenie o udzieleniu patentu
pdf
666285
2016-10-28
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-
Faraj R., Graczykowski C., Holnicki-Szulc J.
Absorber pneumatyczny o adaptowalnej charakterystyce odpowiedzi, wypełniony powietrzem atmosferycznym, zwłaszcza do łagodzenia przyziemienia zrzucanych ładunków
PL, Instytut Podstawowych Problemów Techniki PAN, Adaptronica Sp. z o.o.
-
-
-
407160
2014-02-12
BUP 17/15
2015-08-17
Graczykowski C., Pawłowski P., Holnicki-Szulc J.
Sterowalny zawór bistabilny zwłaszcza do gazowego absorbera energii
PL, Instytut Podstawowych Problemów Techniki PAN
-
-
-
397312
2011-12-09
BUP 12/13
2013-06-10
Świercz A., Mikułowski G., Wiszowaty R., Holnicki-Szulc J., Kołakowski P., Graczykowski C.
Sposób generowania wstępnie zaprojektowanego udarowego obciażania konstrukcji oraz urzadzenie do generowania wstępnie zaprojektowanego obciążania konstrukcji
PL, Adaptronica Sp z o.o., Instytut Podstawowych Problemów Techniki PAN
221709
WUP 05/16
2016-05-31
390194
2010-01-28
BUP 16/11
2011-08-01
Wiszowaty R., Graczykowski C., Sekuła K., Holnicki-Szulc J.
Sposób identyfikacji prędkości zderzenia, masy oraz energii kinetycznej obiektu uderzającego w przeszkodę i urządzenie do identyfikacji prędkości zderzenia, masy oraz energii kinetycznej obiektu uderzającego w przeszkodę
PL, Adaptronica Sp z o.o.
219996
WUP 08/15
2015-08-31
387534
2009-03-18
BUP 20/10
2010-09-27
Graczykowski C., Mikułowski G., Mróz A., Sekuła K.
Sposób dyssypacji energii uderzenia obiektu i absorber pneumatyczny
PL, Adaptronica Sp z o.o.
214845
WUP 09/13
2013-09-30
385086
2008-05-02
BUP 23/09
2009-11-09
Ostrowski M., Graczykowski C., Pawłowski P.
Zawór sterowany zwłaszcza do poduszki gazowej
PL, Adaptronica sp. z o.o.
212619
WUP 10/12
2012-10-31