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  1. 5 Acta of Bioengineering and Biomechanics
  2. 4 Przegląd Elektrotechniczny
  3. 3 Acta Mechanica et Automatica
  4. 2 Diagnostyka
  5. 2 International Journal of Applied Mechanics and Engineering
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  1. 4 Sapiński B.
  2. 2 Chladek G.
  3. 2 Krupa S.
  4. 2 Żmudzki J.
  5. 1 Alim Md. Abdul
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1
Content available Influence of elements fastening system type sb for chosen exploitation parameters
Chudyba Łukasz, Lisowicz Tomasz
Journal of civil engineering and transport
|
2024
|
Vol. 6, No 1
39--49
EN
The paper presents a comparative analysis of the clamping force on the operating parameters of the SB fastening system. An overview of used elastic fastening systems for prestressed concrete sleepers is presented. The results of laboratory research carried out in accordance with the applicable European standards of the PN-EN 13481 and PN-EN 13146 series are described synthetically. Specially prepared clamp type SB with different stiffness within the range allowed by PKP PLK S.A. were selected for the tests. All tests were done in accredited laboratory. The paper presents the impact of the SB clamp stiffness on the basic parameters of the fastening system, such as the clamping force and longitudinal resistance. A reduced value of the static stiffness of the clamp may fail to fulfill the requirements of the fastening system shown in the Technical Specifications for Interoperability. The risk of non-repeatability of the SB clamp should lead to the development of a solution or even a change to the W-type fastening system.
PL
W pracy przedstawiono analizę porównawczą wpływu siły docisku generowaną poprzez elementy realizujące docisk na wybrane parametry eksploatacyjnych systemów przytwierdzeń typu SB. Przedstawiono przegląd stosowanych sprężystych systemów przytwierdzeń do podkładów strunobetonowych. Opisano syntetycznie wyniki badań laboratoryjnych prze-prowadzonych zgodnie z obowiązującymi normami europejskimi serii PN-EN 13481 i PN-EN 13146. Do badań wybrano specjalnie przygotowane łapki SB o różnych sztywnościach w zakresie dopuszczalnym przez PKP PLK S.A.. Badania wykonano a akredytowanym laboratorium. W pracy przedstawiono wpływ sztywności łapki sprężystej na podstawowe parametry systemu przytwierdzenia takie jak siła docisku oraz opór wzdłużny. Obniżona wartość sztywności statycznej łapki może spowodować brak spełnienia wymagań systemu przytwierdzenia stawianym przez Techniczne Specyfikacje Interoperacyjności. Ryzyko braku powtarzalności wykonania łapki SB, powinno prowadzić do rozwoju rozwiązania lub nawet zmiany na system przytwierdzenie typ W.
2
Content available remote Laboratory study of the effects of terrestrial coastal forests on the absorption of solitary wave force
Mirzakhani Golnaz, Ghanbari-Adivi Elham, Fattahi Rohollah
Acta Geophysica
|
2024
|
Vol. 72, no. 1
449--465
EN
One of the beach protection techniques is using natural methods based on the coastal ecosystem. Studies show the reducing effect of forest covers on wave destruction intensity in different areas. However, it is not yet well understood how various densities of terrestrial coastal forest (TCF) affect the wave attenuation and reduce their strength. Studying the impact of various forest parameters, such as density, distance, and arrangement type on the wave force attenuation, this research measures the wave forces directly. TCF model was installed in a knife edge flume, which equipped with a load cell and an acoustic Doppler velocimeter. The experiments were performed in two staggered and parallel arrangements consisting of different densities from 12 to 273 stems per unit area. Based on obtained results, TCF had significant effects on the wave force absorption. An increase in the number of trees (density) increased TCF resistance force and the absorbed wave force. In its best, the TCF could absorb the wave force 3.76 times more than the no-TCF case. It could reduce the wave height by up to 81% at the highest density and maximum wave height. The absorbed wave force and drag coefficient rose as the number of rows of trees opposing the flow decreased and the intervals between trees were shortened. Increasing tree density from 12 to 273 stems per unit area increased the drag coefficient by the average of 61.82% for parallel and staggered arrangements, which means an average increase of 9.7% for each TCF row.
3
Content available Flexure-based dynamometer for vector-valued milling force measurement
Ramsauer Christoph, Leitner David, Habersohn Christoph, Schmitz Tony, Yamazaki Kazuo, Bleicher Friedrich
Journal of Machine Engineering
|
2023
|
Vol. 23, No. 1
47--56
EN
Variation in cutting forces with cutting parameter selection, tool geometry, and wear status plays an important role for milling process evaluation and modeling. While piezoelectric force measurement is commercially available, it is often considered a precise but expensive method. This paper presents a novel solution for vector-valued cutting force measurement. The table-mounted, flexure-based kinematics provide three degrees of freedom that are used to measure the in-process milling force vector components in the working plane by low-cost optical sensors. Based on analytical models and FEM analysis, an appropriate design was derived. The assembly and testing of the developed dynamometer are presented. A test setup based on a machining center was used for the system evaluation and the data are compared to the forces measured by a commercially available, piezoelectric cutting force dynamometer.
4
Zmiany niwelety stalowego przęsła mostu podwieszonego
Machelski Czesław, Hildebrand Maciej
Inżynieria i Budownictwo
|
2023
|
R. 79, nr 3-4
165--169
PL
W niniejszej pracy skupiono się na analizie zmiany niwelety mostu. Do tego celu wykorzystano wyniki pomiarów geodezyjnych. Z uwagi na złożony kształt wykresów ugięć konieczne było stosowanie korekty, w której korzystano z pomiaru sił w wantach. Jest to jeden ze stosowanych algorytmów wygładzania funkcji ugięcia uzyskanych z pomiarów geodezyjnych. Do analizy skuteczny jest globalny model konstrukcji 2D z wykorzystaniem elementów prętowych. Jest on szczególnie efektywny w zastosowaniu MRS, gdy występuje regularny układ punktów pomiarowych. Zaletą algorytmu jest wybór dowolnego wycinka przęsła i niezależność od warunków podporowych.
EN
The alterations of bridge gradeline is a main subject of the paper. For this purpose, the results of geodetic survey were used. Due to the complex shape of the deflection lines, it was necessary to apply a correction procedure, using the results of measurement of forces in the stays. This is one of the algorithms used to smooth the deflection function obtained from geodetic measurements. A global 2D numerical model with bar elements is effective for the analysis. It is especially effective in MRS applications when there is a regular arrangement of measurement points. The advantage of the algorithm is the selection of any section of the span and independence from the support conditions.
5
Content available Evaluation of forces in a racing simulator based on a Stewart platform
Tytuła Jakub, Zaremba Arnold, Nitkiewicz Szymon
Diagnostyka
|
2023
|
Vol. 24, No. 4
art. no. 2023405
EN
This paper presents how forces are perceived in a racing simulator based on a Stewart Platform. By retrieving calculated forces in a racing game by its physics engine and comparing them to real-life measurements during the platforms motions it is possible to evaluate the platforms immersiveness. Virtual values extracted from the game engine are deemed satisfactory to their real life counterparts and serve as a baseline. In order to evaluate forces created by the simulator, a lap around a virtual test track is recorded and played back while an accelerometer and gyroscope record its movements. Overall, accelerations recorded in the direction of X and Y axis along with angular speed of rotation around the aforementioned those axis. To accurately comparing every derived force, the recorded virtual lap is divided into sections representing the five most common manoeuvres during racing. These comparisons serve as an evaluation method to measure the immersiveness of the simulator.
6
Content available Force exerted by gas on material ejected during gas-geodynamic phenomena analysis and experimental verification of theory
Kozieł Katarzyna, Janus Jakub
Archives of Mining Sciences
|
2022
|
Vol. 67, no. 3
491--508
EN
The analysis of natural hazards, including gas-geodynamic phenomena, requires study of the basic physical processes that take place at each stage of an event. This paper focuses on analysing the transport of fragmented rock material during rock and gas outbursts. Our theoretical considerations and experiments have allowed us to specify and verify the significant forces acting on fragmented rock during its transport, thus determining the speed of grains of each grain class in the stream of expanding gas. The above study may serve as a preface to a wide-ranging quantitative and qualitative energy analysis of the movement of material ejected during Gas-geodynamic phenomena.
7
Content available Performance analysis between a hybrid force/position and conventional controllers for a wrist exoskeleton
Avilés Valeria, Avilés Oscar F., Aponte Jorge, Caldas Oscar I., Mauledoux Mauricio F.
Archives of Control Sciences
|
2022
|
Vol. 32, No. 2
409--427
EN
This study analyses the performances of various path controlling strategies for a 3-degrees of freedom wrist exoskeleton, by comparing key indicators, such as rise time, steady-state error, and implementation difficulty. A model was built to describe both system’s kinematics and dynamics, as well as 3 different controllers (PID, PD+, and a hybrid force/position controller) that were designed to allow each joint to perform smooth motions within anatomic ranges. The corresponding simulation was run and assessed via Matlab (version 2020a). In addition to the performance comparison, remarkable characteristics could be identified among controllers. PD+ showed higher response speed than the other controllers (about 4 times), and PID was reinforced as the technique with the easiest implementation due to the smallest matrices. The study also allowed to greater potential of the hybrid controller to interact with its environment, i.e., the robotic device.
8
Content available remote 10 Opolska Brygada Logistyczna w aspekcie realizowanych zadań zabezpieczenia logistycznego Sił Zbrojnych RP
Płuciennik Piotr
Systemy Logistyczne Wojsk
|
2021
|
Vol. 55, no. 2
61--78
PL
Efektywne zabezpieczenie logistyczne wojsk, wymaga posiadania odpowiedniego potencjału. Planowane do użycia siły i środki muszą zostać tak skalkulowane, aby w każdych warunkach usługi logistyczne, a w tym dostawy środków bojowych i materiałowych docierały w odpowiednie miejsce, w odpowiednim czasie oraz w odpowiedniej ilości i jakości. W 1999 roku, w odpowiedzi na wyzywania współczesnej logistyki wojskowej powstała 10 Opolska Brygada Logistyczna. Była to pierwsza w Wojsku Polskim jednostka wojskowa, przeznaczona do wsparcia logistycznego Polskich Jednostek Wojskowych wykonujących zadania w kraju i poza jego granicami. Autor postawił na wstępie hipotezę, że najprawdopodobniej 10 Opolska Brygada Logistyczna odegrała znaczącą rolę w aspekcie realizowanych zadań zabezpieczenia logistycznego Sił Zbrojnych Rzeczypospolitej Polskiej. W toku prowadzonych badań hipoteza ta została zweryfikowana pomyślnie. Celem artykułu było również znalezienie odpowiedzi na pytanie czy podjęte w 1999 roku rozwiązanie organizacyjne utworzenia 10 Opolskiej Brygady Logistycznej sprawdziło się w aspekcie realizowanych zadań zabezpieczenia logistycznego Sił Zbrojnych. Cel główny został zrealizowany poprzez przedstawienie 10 Opolskiej Brygady Logistycznej, jej roli i przeznaczenia, aktualnie posiadanego potencjału oraz głównych zadań realizowanych w kraju jak i w misjach poza jego granicami na rzecz Polskich Kontyngentów Wojskowych. Ukazano również wysiłek brygady włożony we wsparcie administracji publicznej w walkę z pandemią koronawirusa SARS-CoV-2 oraz współpracę w tym obszarze i wsparcie logistyczne jednostek wojsk operacyjnych oraz innych służb mundurowych. Podjęcie tej problematyki wynikało z potrzeby uzupełnienia wąskiego katalogu dostępnych opracowań na temat funkcjonowania opolskiej jednostki. Do przeprowadzenia badań wykorzystano literaturę oraz dokonano analizy aktualnych danych uzyskanych z poszczególnych sekcji Pionu Logistyki, Szefa Sztabu oraz Pionu Szkolenia 10 Opolskiej Brygady Logistycznej.
EN
The effective logistic support to military requires the possession of adequate potential. Forces and means planned to be used have to be calculated, so in all conditions logistic services to include delivery of ammunition and other material means arrive at the right time, at the right place, at the right quantity as well as the right quality. In 1999, as a response to then requirements of military logistics the 10th Logistic Brigade was founded. It was the first military unit in Polish Armed Forces designated to provide logistic support to Polish military units in and outside the country. The author formulated the hypothesis that most probably the 10th Opolska Logistic Brigade played an important role in providing logistic support to Polish Armed Forces. The indicated hypothesis was confirmed right during the study. Another reason of this article was to find an answer to the question if the decision of founding of the 10th Logistic Brigade in 1999 was pertinent taking into consideration performing logistic tasks in favor of Polish Armed Forces. The article showed the role, the purpose and the up to the date potential of the 10th Logistic Brigade. It also presented a wide range of tasks performed by personnel of this military unit in as well as outside the country where providing logistic support to Polish Military Contingents. In the article author introduced the picture of effort that was performed by soldiers and civilian personnel of the 10th Logistic Brigade during the fight against SARS-CoV-2 pandemic. This part of the article also presented the cooperation with local authorities as well as other uniformed services. This study addressed the above mentioned issues because there was a very small amount of available works concerning the subject of military unit from Opole. In the study the up to date data of the Logistics Department, the Training Department and the Chief of Staff of the 10th Logistic Brigade was used.
9
Content available Destruction of the Structure of Boiling Emulsions
Pavlenko Anatoliy, Melnyk Viktor
Rocznik Ochrona Środowiska
|
2020
|
Tom 22, cz. 1
70--81
EN
In this paper we consider the processes of dynamic interaction between the boiling particles of the dispersed phase of the emulsion leading to the large droplet breakup. It is indicated the differences in the consideration of forces that determine the crushing of non-boiling and boiling drops. It is determined the possibility of using the model to define the processes of displacement, deformation or fragmentation of the inclusion of the dispersed phase under the influence of a set of neighboring particles. The proposed method allows us to determine the main energy parameters of the homogenization process by boiling the emulsion.
PL
W tym artykule rozważamy procesy dynamicznej interakcji między wrzącymi cząsteczkami zdyspergowanej fazy emulsji, prowadzące do rozpadu dużych kropel. Wskazano na różnice w uwzględnianiu sił, które determinują kruszenie kropli niewrzących i wrzących. Określono możliwość wykorzystania modelu do zdefiniowania procesów przemieszczenia, deformacji lub fragmentacji włączenia fazy rozproszonej pod wpływem zestawu sąsiednich cząstek. Proponowana metoda pozwala określić główne parametry energetyczne procesu homogenizacji podczas ogrzewania i wrzenia emulsji.
10
Content available remote Magnetic levitation in industrial transport systems
Lis Marek, Szewczyk Krzysztof, Walasek Tomasz
Przegląd Elektrotechniczny
|
2020
|
R. 96, nr 12
214--217
EN
The paper presents a well known idea of using permanent magnets as a source of energy in an industrial transport system (for instance maglev). The idea of this paper is to present computation and simulation for a transport system in 2D space using the Ansys environment. An idea for a system which starts to operate only at the very moment when a worker needs help and is moving a heavy object, and is using it with a minimum amount of energy has become an idea about saving energy. When gravity is eliminated by magnetic fields forces, for moving heavy object, we only need to overcome the moment of inertia. All resistance practically disappears, because there is almost no friction in this system. In the paper the use of magnetic field concentration in Halbach array system for eliminating gravitational forces during a load movement has been presented.
PL
W pracy przedstawiono dobrze znaną ideę wykorzystania magnesów trwałych, jako źródła energii w przemysłowym systemie transportu (na przykład maglev). Ideą tego artykułu jest prezentacja obliczeń i symulacji transportu systemu w przestrzeni 2D za pomocą środowiska Ansys. Pomysł na system, który działa tylko w momencie, gdy pracownik potrzebuje pomocy i porusza ciężkim przedmiotem i używa go przy minimalnej ilości energii, staje się pomysłem oszczędzania energii. Kiedy grawitacja jest eliminowana przez siły pola magnetycznego, do przemieszczania ciężkich obiektów wystarczy jedynie pokonać moment bezwładności. Cały opór praktycznie znika, ponieważ w tym układzie prawie nie ma tarcia. W artykule przedstawiono zastosowanie koncentracji pola magnetycznego w układzie macierzy Halbacha do eliminacji sił grawitacyjnych podczas ruchu ładunku.
11
Content available Udział Głównego Urzędu Miar w europejskim projekcie badawczym EMPIR w dziedzinie siły
Fidelus Janusz D.
Metrologia i Probiernictwo : biuletyn Głównego Urzędu Miar
|
2020
|
nr 1 (24)
7--14
PL
W artykule przedstawiono założenia i szczegółowe cele projektu oraz aktualny stan wiedzy i możliwości uzyskania postępu w zapewnieniu spójności pomiarowej w europejskim i światowym przemyśle w zakresie siły statycznej, ciągłej i dynamicznej. Omówiono także zakres uczestnictwa GUM oraz potencjalny wpływ założonych w projekcie przedsięwzięć na środowisko, metrologię i użytkowników. Przedstawiono wzorce GUM o najmniejszej niepewności pomiarowej, na których zostaną wykonane badania siły statycznej i ciągłej.
EN
The article presents the assumptions and detailed objectives of the project as well as the current state of the art and the possibilities of achieving progress in ensuring traceability in European and global industry in the field of static, continuous and dynamic force. The scope of GUM participation and the potential impact of the design assumptions on the environment, metrology and users were also discussed. GUM standards with the lowest measurement uncertainty, on which static and continuous force tests will be performed, are presented.
12
Content available Wpływ kształtu imperfekcji geometrycznych dźwigarów dachowych na siły w tężniku połaciowym poprzecznym
Czepiżak Dariusz
Builder
|
2020
|
R.24, nr 4
88--91
PL
Projektując stężenia połaciowe poprzeczne [1], zaleca się przyjmować zastępcze obciążenie od imperfekcji geometrycznych dźwigarów dachowych. Obciążenie to można bezpiecznie oszacować [1] przy założeniu stałej na długości elementu stabilizowanego siły ściskającej i imperfekcji w kształcie paraboli o strzałce e0. W pracy, dla różnych kształtów imperfekcji geometrycznych elementów stabilizowanych, wyznaczono obciążenia imperfekcyjne oraz siły w prętach tężnika połaciowego i porównano je z siłami wyznaczonymi wg [1]. Wyniki analiz przedstawiono w tabeli i sformułowano syntetyczne wnioski.
EN
During designing transverse roof bracing, [1] recommends taking into account equivalent stabilizing load from geometrical imperfections of roof girders. This load can be safely estimated [1] assuming a constant compression force along the length of the stabilized element and initial parabolic imperfection with maximum amplitude e0. In the paper, for different shapes of geometrical imperfections of stabilized elements, imperfect loads and forces in the roof bracing were determined and compared with the forces determined according to [1]. The results of the analyzes are presented in the table and synthetic conclusions were formulated.
13
Content available Automotive mr shock absorber behaviour considering temperature changes: experimental testing and analysis
Jastrzębski Łukasz, Sapiński Bogdan, Kozieł Arkadiusz
Acta Mechanica et Automatica
|
2020
|
Vol. 14, no. 1
22--28
EN
This study investigates the automotive magnetorheological (MR) shock absorber behaviour in conditions of changing temperature. Its temperature-dependent behaviour was quantified between ambient and maximal operating temperatures of the device. Aspects addressed include the temperature dependence of the control coil resistance in the absorber, the influence of operating current level on control coil temperature and the temperature dependence of the absorber force response and energy dissipation in the system. The results of experiments enabled us to evaluate the mechanical performance of the absorber at varied temperatures.
14
Content available Calculation the moments of force equation, with use method T6, including kinetic interaction
Godzwa Marek
Selected Engineering Problems
|
2019
|
nr 8
15--21
EN
This article presents the possibilities of the popular T6 method in robotics, bring this method to the designers of mechanics, technology and architects. Presented description of the method concerns the moments equation for different classes of robots, but it can be used wherever it occurs need to calculate the working force for arm. The T6 method can significantly accelerate and simplify calculations, which are also more reliable, with less the possibility of appearing an error. The T6 method also allows the calculation of much more complicated equations, like calculation the acting force of arm, which is not possibly making in the classic way.
15
Content available Mechanical and mathematical research of local deformations of a steel roller shell with a variable geometry of contact surface
Doudkin Mikhail, Kim Alina, Sakimov Murat
Production Engineering Archives
|
2019
|
Vol. 23
27--35
EN
The article is devoted to solving the fundamental and applied problem of nonlinear structural me-chanics of machines by introducing into the drum two additional stop cylinders with supporting rollers at the end and adjustable length, providing a given elliptical or circular shape of a flexible shell with a smoothly variable geometry in the area of its contact with compacted pavement material. Compaction of soil, gravel and asphalt concrete in the sphere of road is not only an integral part of the technological process of the roadbed, road foundation and surface construction, but it is actually the main operation to ensure their strength, stability and durability. The quality, cost and speed of road construction, the possibility of using fundamentally new technologies, structures and materials is largely determined by the availability of modern road machinery.
16
Content available An experimental study of cutting fluid on drilling AISI 1040 steel
Alim Md. Abdul, Uddin Md. Julhash, Islam Md. Ariful
Journal of Mechanical and Energy Engineering
|
2019
|
Vol. 3, No 1
7--12
EN
This experimental study investigated the effects of a conventional cutting fluid during drilling cylindrical holes on workpiece materials made of the AISI 1040 steel. Drilling responses were compared between dry and wet (in presence of the cutting fluid) cutting conditions with respect to drilling force, roundness deviation and taper of the hole, and chip morphology. High production machining and drilling with high cutting speed, feed, and depth of cut were found to be inherently associated with the generation of a large amount of heat and high cutting temperature. In a dry condition such high cutting temperature not only reduces dimensional accuracy and tool life but also impairs the roundness deviation and taper of the hole. The use of a conventional cutting fluid, in such a situation, was very effective to reduce the cutting temperature. In a dry cutting condition, numerous tool-wears were found on the drill bits. Drilling in such a dry condition seriously affects roundness of the hole, and chip shape and color. Contrastingly, use of a traditional cutting fluid reduced temperature as well as improved roundness and taper of the hole. It also acted as a lubricate at the tool tip–work surface interface. Overall, the conventional cutting fluid enhanced the quality of the machine work and potentially can increase machine life of drill bits.
17
Content available Assessment of distribution of plantar pressures and foot characteristics during walking in pregnant women
Mikeska Ondřej, Gimunová Marta, Zvonař Martin
Acta of Bioengineering and Biomechanics
|
2019
|
Vol. 21, no. 3
49--56
EN
The main purpose of this research was to analyse the distribution of plantar pressures and foot characteristics during walking between weeks 27 and 36 of pregnancy. The secondary purpose was to test the effect of the customized orthopaedic shoes that were worn by the experimental group. Methods: Pregnant women (n = 73) were divided into 2 groups, control group (n = 38) and experimental group (n = 35) which completed 5 gait trials on a walkway (1.55m) at a self-selected velocity of gait, where force, pressure and remaining foot characteristics were sampled and displayed by Novel database pro m (version 25.3.24). Results: Analysis of foot characteristics did not reveal important changes. Analysis of the distribution of plantar pressures revealed few changes in the pre- and post-measurement of the experimental and control groups between weeks 27 and 36 of pregnancy. In the last measurement, there is a significant increase of peak pressure only in the midfoot area of the left foot (151.1 ± 41.2 kPa) and in the hindfoot area of the right foot (346.3 ± 104.1) of the experimental group. The control group exhibits similar pressure development for both of foot. Conclusions: Monitored parameters demonstrated in certain areas notably development of force and contact area. Results of foot characteristics did not reveal a significant changes. As both groups registered similar values in certain areas in a comparison of pre/post measurement characteristics, the influence of specific orthopaedic shoes cannot be conclusively demonstrated in the experimental group.
18
Content available Bucket wheel excavator cutting tooth stress and deformation analysis during operation using Finite Elements Method (FEM)
Brinas I. K., Rebedea N. I., Oltean I. L.
Mining – Informatics, Automation and Electrical Engineering
|
2018
|
R. 56, nr 4
9--13
EN
In the case of bucket wheel excavators, the cutting process is influenced by the forces opposing the working elements and cutting tools. These forces determine the choice of machines and their parameters as well as the operating method [1, 2]. Studies conducted on the failure causes of mechanical parts show that the cutting and loading systems cause the highest rate of failure – about 32% of all recorded mechanical failures [3]. In this paper, we will use the Finite Element Method (FEM) to analyze the deformations and stresses acting on the cutting teeth mounted on the rotor of BWEs. For this, Solid- Works® software was used, both as a CAD tool to design the teeth as well as to model and simulate the phenomena.
19
Content available Analysis of force in MR fluids during oscillatory compression squeeze
Horak W., Szczęch M., Sapiński B.
Acta Mechanica et Automatica
|
2017
|
Vol. 11, no. 1
64--68
EN
This study investigates the behaviour of MR fluids in the oscillatory compression squeeze mode. Experiments were performed on commercially available MR fluids in the purpose-built experimental set-up. The influence of MR fluid’s properties and magnetic flux density on the force generated during the squeeze mode was investigated.
20
Content available Quantum mechanical aspects in the MEMS/NEMS technology
Słowik O., Orłowska K., Kopiec D., Janus P., Grabiec P., Gotszalk T.
Measurement Automation Monitoring
|
2016
|
Vol. 62, No. 3
87--91
EN
According to the scaling laws for nanomechanical resonators, many of their metrological properties improve when downscaled. This fact encourages for constant miniaturization of MEMS/NEMS based sensors. It is a well known fact, that the laws of classical physics cannot be used to describe the systems which are arbitrarily small. In consequence, the classical description of nanoresonators must break down for sufficiently small and cool systems and then the quantum effects cannot be neglected. One of the fundamental question which arises is, how one may investigate quantum effects in MEMS/NEMS sensors and what is the influence of quantum effects on the performance of such systems. In this paper we would like to raise those issues by presenting the results of our work related to our estimations and calculations of MEMS/NEMS dynamics. The first and second sections are of theoretical character. In the first section (Classical modeling), we describe the classical methods for describing the resonator dynamics and the classical limit on the resolution of MEMS/NEMS based force sensors, which is set by the thermomechanical noise. In the second section (Quantum aspects), we concentrate on the quantum description of micro and nanoresonators and the influence of quantum effects, such as zero-point motion and back-action, on their performance (quantum limits). The third section is devoted to the presentation of our experimental methods of MEMS/NEMS deflection metrology, i.e. Optical Beam Deflection method (OBD) and fibre optics interferometry.
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