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1

Research on an Innovative FLEX Bicycle Frame with a Softtail Vibration Damping System

Kuczek Łukasz, Marczak Paweł, Muzykiewicz Wacław, Mroczkowski Marcin, Paćko Paweł, Drop Dawid

Advances in Science and Technology. Research Journal

|

2023

|

Vol. 17, no 1

290--303

EN

Bicycles are gaining more and more popularity, especially in crowded cities where there is a problem with traffic jams and a limited number of parking spaces. The bicycles are also often used by mountain bikers during riding on off-road trails. In both cases, the important parameters are the stiffness of the bicycle frame, the weight of the bicycle, but also driving comfort. To improve comfort and reduce vibrations in the bicycle frame both front and rear shock absorbers are used. The use of traditional shock absorbers increase the weight of the bike and its price. The work characterizes a modern damping system, Softtail type, designed by AG Motors. In this case, the damping element (elastomer) was placed directly in the rear fork. Analyses of polyurethanes of various hardness were carried out in terms of the possibility of using them as a vibration damper. A numerical and experimental analysis of the bicycle frame was performed, adapted to the a new shock-absorber system. Strength, fatigue and impact tests were carried out in accordance with the relevant bicycle standards. Research has shown that the frame bicycle with the Softtail system, meets the requirements of the standards.

2

Finite element analysis on prosthetic leg under different loads and flexion angles for medical applications

Konada Naresh Kumar, Koka Naga Sai Suman

Journal of Mechanical and Energy Engineering

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2022

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Vol. 6, No 2

1--12

EN

Prosthetic legs are mainly used to perform leg amputations more easily and sometimes the appearance is similar to a real leg. Different types of legs have been developed in recent days to be used in specific fields like running, cycling in sports and normal walking. The selection of materials and load bearing capacity of a leg determines its usage for any field of application. The behavior of prosthetic legs can be assessed properly by performing a finite element analysis on it with varying material properties and loads before it undergoes a designing and manufacturing stage. In the current study, Al alloy, Ti alloy, unidirectional Carbon fiber epoxy (UDCFE) and combined composite material which include (CF, UDCFE and Ti alloy) are used as materials for the prosthetic leg. A prosthetic leg model of C Type with its main parts being the sleeve, the rod and the base foot was designed initially by using the Solid Works 2010 software and the assembled file was imported to Ansys Workbench 2020 to perform a static and fatigue analysis. The static analysis was performed under four different load conditions, i.e. 60 kg, 70 kg, 80 kg and 90 kg, considering the different human weights of the body. A fatigue analysis was done by using the Soderberg method and applying a sinusoidal varying load for low cycle fatigue conditions. Theoretical calculations were also performed at various inclinations of foot 10°, 20°, and 30° with the ground and stresses were evaluated using finite element equations. The results obtained theoretically were compared with the analytical results. The best material which provided the lesser value of deformation and sustaining more loads with a lower value of the damage factor was selected for the design. Further experimental studies were suggested based on the results obtained from this work.

3

Design and analysis of cementless hip-joint system using functionally graded material

Asiri Saeed

Archive of Mechanical Engineering

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2022

|

LXIX, nr 1

129--146

EN

Functionally Graded Materials (FGM) are extensively employed for hip plant component material due to their certain properties in a specific design to achieve the requirements of the hip-joint system. Nevertheless, if there are similar properties, it doesn’t necessarily indicate that the knee plant is efficiently and effectively working. Therefore, it is important to develop an ideal design of functionally graded material femoral components that can be used for a long period. A new ideal design of femoral prosthesis can be introduced using functionally graded fiber polymer (FGFP) which will reduce the stress shielding and the corresponding stresses present over the interface. Herein, modal analysis of the complete hip plant part is carried out, which is the main factor and to date, very few research studies have been found on it. Moreover, this enhances the life of hip replacement, and the modal, harmonic, and fatigue analysis determines the pre-loading failure phenomena due to the vibrational response of the hip. This study deals with the cementless hip plant applying the finite element analysis (FEA) model in which geometry is studied, and the femoral bone model is based in a 3D scan.

4

Digital Twin For Fatigue Analysis

Chabod Amaury, Baron Nicholas

Fatigue of Aircraft Structures

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2020

|

Iss. 12

47--56

EN

The main design parameters that impact the fatigue of components are geometry, material and loading. Simulation with Finite Element Analysis (FEA) and tests on a vibrating table are often used to understand the dynamic behaviour of components and thus validate those items. Accelerated tests are used for the mission profile and test definition, as described in GAM-EG-13, MIL-STD-810F and RTCA DO-160E. The shock response spectrum (SRS) and the extreme response spectrum (ERS) allow for a comparison of the power spectrum density (PSD) and the acceleration factor applied in terms of fatigue severity through the fatigue damage spectrum (FDS). In addition, the hypothesis of linear damage accumulation enables the combination of several events for specifying a mission profile. Ultimately, the mission profile, which represents a usage that might span over several years, can be reduced to a shorter duration with a damage extraction technique. This is particularly useful for the definition of vibrating table specifications. An advantage of the virtual vibrating table is the reduction of the number of prototypes and the understanding of failure modes. To achieve this objective, finite element analysis in the frequency domain (harmonic analysis) is used and the structural stress response is evaluated with a PSD loading. A statistical model of rainflow allows assessing the damage on the components. The presentation also shows the effects of the damping factor on damage results. To achieve accurate results and define a Digital Twin, the correlation between test results and the finite element analysis is fundamental. Experimental modal analysis, based on the measured acceleration responses, helps to validate calculated modal frequencies and to assess the damping for each mode. This study shows the importance and the sensitivity on damping of the structural response, and in turn on fatigue.

5

Fatigue Life Predicting for Nitrided Steel - Finite Element Analysis

Sawicki J., Siedlaczek P., Staszczyk A.

Archives of Metallurgy and Materials

|

2018

|

Vol. 63, iss. 2

921--927

EN

Thermo-chemical treatments are known to increase the fatigue life of industrial parts. Due to the imprecise consideration of residual stresses in predicting the durability of components subjected to cyclic loading and their effect on the fatigue life, the authors developed a numerical model combining the influence of residual stresses with stresses caused by bending. The authors performed the numerical simulation with the use of Finite Element Method to analyse material behaviour during cyclic loading. The residual stress state developed during nitriding was introduced onto cross-section of the numerical specimen. The goal of this work was better understanding of the real conditions of the nitride steel fatigue processes and improving the knowledge about numerical predicting of the fatigue life for parts with residual stresses. The results of simulation were compared with plane bending fatigue tests. The presented method indicates the possibility of increasing the accuracy of the fatigue analysis of elements after surface treatment, increasing its certainty and the ability to perform better optimization of service life.

6

Fatigue assessment procedure for old riveted road bridges

Kużawa M., Kamiński T., Bień J.

Archives of Civil and Mechanical Engineering

|

2018

|

Vol. 18, no. 4

1259--1274

EN

The paper proposes a comprehensive, experimentally supported fatigue evaluation procedure dedicated to old riveted road bridges. The presented fatigue assessment of old riveted structures, very often of high historical value, is performed according to general assumptions of the Eurocodes [1], [2] and the European Recommendations for Estimation of Remaining Fatigue Life of Existing Steel Structures [3]. Essential input data used for estimation of the fatigue damage accumulation in critical bridge components as well as for prediction of residual lifetime of the whole structure is based on experimental vibration tests performed under real live loads. An original approach related to the experiment-based adaptation of the standardised fatigue loads [1], [2] to the individual operating conditions of each structure is proposed and defined in details. Its practical implementation is described in a case study of a typical historical 80-year-old road bridge crossing the Vistula River in Puławy in Poland. In the previous decades, the bridge despite of its advanced age and historical value was intensively exploited by heavy vehicles. Thus, taking into account the age of the structure and intensity of the traffic crossing the bridge the remaining fatigue resistance of the bridge critical members was evaluated by means of the proposed procedure.

7

Comparison of results of stress cycle counting by the direct spectral method and the Fu-Cebon method for bi-modal type stress processes

Kozień M. S., Smolarski D.

Technical Transactions

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2017

|

Vol. 2(114)

167--177

EN

This article compares the results of a high cycle fatigue analysis obtained through the application of the two methods dedicated to analysis of response of the structure of the bi-modal type – the direct spectral method and the Fu-Cebon one. The compared parameter is the lifetime for an assumed material S–N curve and stress spectrum defined in an article by Fu & Cebon.

PL

W artykule dokonano porównania rezultatów wysokocyklowych analiz zmęczeniowych wykonanych przy zastosowaniu dwu metod dedykowanych dla przypadków odpowiedzi struktury o charakterze dwumodalnym: metody spektralnej bezpośredniej i metody Fu-Cebona. Porównywaną wielkością był czas życia konstrukcji przy założonej postaci krzywej S–N materiału i zmienności naprężeń o charakterystyce wykorzystywanej w artykule Fu i Cebona.

8

A Fatigue Fracture Study on TDCB Aluminum Foam Specimen of Type Mode III Bonded with Adhesive

Lee J. H., Cho J. U.

Archives of Metallurgy and Materials

|

2017

|

Vol. 62, iss. 2B

1359--1362

EN

This paper studies the characteristics of junction structure of closed-cell type aluminum foam, which is generally used as a shock absorber. TDCB specimens were designed for mode III type with thickness as a variable and performed a fatigue experiment on them by thickness. As the result, the load value of all specimens peaks under 0 to 25 cycles and decreases as the cycles increase. As the specimen thickens by 10 mm, the maximum load value is 1.2 times. When the thickness increases by 20 mm, the maximum value increases by 1.5 times. This study result can be utilized by investigating the mechanical characteristics of TDCB specimens for mode III type under fatigue loading conditions systematically and efficiently.

9

Analysis of axle shaft fatigue failure and anti-fatigue system design

İrsel G.

Advances in Science and Technology. Research Journal

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2017

|

Vol. 11, no 3

150--163

EN

In this study, an axle shaft subjected to static deformation and fatigue damage was considered by using computer-aided engineering. This shaft system was modeled with CATIA and subjected to dynamic fatigue analyses with Ansys workbench. The damaged fracture surfaces of the shaft have been examined. Thus, the fatigue and damage was revealed in greater detail. For the present system, a design with a minimum cost, short production process, minimum weight was sought together with methodical construction principles. By means of CATIA and ANSYS, the product development design with reasonable tension and deformation values was formed for endless life fatigue. A design was produced in a short space of time with the help of 2D CATIA drawings and field tests were carried out. The design was used through 560.000 cycles and damage was not observed.

10

Fatigue Analysis of Automative Steering Knucle

Madhusudhanan S., Arun Kumar K., Praveen Kumar V., Mahendran T.

Mechanics and Mechanical Engineering

|

2016

|

Vol. 20, nr 1

5--13

EN

Steering knuckle plays a vital role in automobile which connects the suspension, steering part, wheel hub and brake to the chassis. During its working, it subjected to various loading conditions. so, it requires high accuracy,, quality, and durability. The main theme of this work is to access the fatigue performance of a steering knuckle. This can be performed by a detailed load analysis. Therefore, this study requires two steps. First part of the study involves modeling of the steering knuckle with the design parameters using the latest modeling software CATIA and the second part involves in fatigue analysis using ANSYS WORKBENCH. This provides us to improve the overall knowledge about the component.

11

Application of the direct spectral method to cycle identification for multiaxial stress in fatigue analysis

Kozień M. S., Smolarski D.

Czasopismo Techniczne. Mechanika

|

2016

|

Y. 113, iss. 5-M

53--61

EN

In the article, the means of application of the direct spectral method for the identification of the stress cycles for multiaxial stress is discussed. Two cases are analyzed. The first, when components of stress tensor are in phase, and the second, when they are shifted in phase. The second case is associated with the practical application for the crane wheel.

PL

W artykule przedstawiono sposób zastosowania metody spektralnej bezpośredniej do identyfikacji cykli naprężeń o charakterze wieloosiowym. Rozważane są dwa przypadki. Pierwszy, gdy składowe tensora naprężeń są zgodne w fazie i drugi, gdy są one przesunięte w fazie. Drugi przypadek jest związany z praktycznym zastosowaniem dla koła suwnicy.

12

Assessment of Durability of the Toothed Segment Based on FEM Analysis and Low Fatigue Cycle Test

Piekło J., Maj M., Żuczek R., Pysz S.

Archives of Foundry Engineering

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2016

|

Vol. 16, iss. 4

113--118

EN

The development of a novel design for the toothed segment of drive transmission in longwall shearer is expected to significantly reduce the cost of individual components of the feed system and the related work of repair and renovations, increasing at the same time the safety of mine repair teams. The conducted experimental and numerical analysis of the state of stress and strain in the innovative design of the toothed segment has enabled estimating the maximum effort of the developed structure. Based on the results of fundamental mechanical studies of the cast L20HGSNM steel and fatigue tests combined with the numerical stress/strain analysis, the fatigue life curve was plotted for the examined casting of the rack.

13

Analiza statyczna oraz zmęczeniowa wału maszynowego z wpustem czółenkowym

Piotrowski M., Witek L.

TTS Technika Transportu Szynowego

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2015

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R. 22, nr 12

1235--1240, CD

PL

Praca przedstawia wyniki obliczeń statycznych oraz zmęczeniowych dotyczących wału maszynowego z wpustem czółenkowym. W pierwszej części pracy opisano poszczególne etapy tworzenia modelu numerycznego połączenia składającego się z wału, wpustu czółenkowego oraz fragmentu współpracującego koła zębatego. Następnie zdefiniowano warunki brzegowe, obciążenia oraz model materiału. W strefie styku wpustu z elementami współpracującymi zdefiniowano kontakt typu Coulomba. Wyniki analizy wykonanej przy użyciu metody elementów skończonych pozwoliły na ustalenie wpływu wybranych parametrów konstrukcyjnych wpustu czółenkowego oraz rowka pod wpust na poziom naprężeń w wale maszynowym. Określono również wpływ kształtu połączenia czółenkowego na wartość zmęczeniowego marginesu bezpieczeństwa dla wybranych przebiegów obciążeń nisko i wysokocyklowych w wale maszynowym. W ostatniej części pracy sformułowano wnioski końcowe o charakterze zarówno ilościowym jak również jakościowym.

EN

In this work the result of static and fatigue calculations of the Woodroff key were presented. This key is used in order to connect of the gear wheel and the shaft. In first step of the work, the analytical calculation was carried out, in order to obtain Woodruff key’s geometrical parameters. After that several numerical models with different geometry were made. As a result of numerical calculations the stress contours for the shaft, the Woodroff key and for the gear was performed. The influence of geometrical parameters of the joint on value of the stress concentration factor was additionally analyzed. In the last step of the work the fatigue safety margin was computed for the shaft with different geometrical parameters.

14

Application of the concurrent designing in virtual model development of a new generation of cereal drill construction

Szczepaniak M., Rogacki R., Dudziński P., Olejniczak M.

Journal of Research and Applications in Agricultural Engineering

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2015

|

Vol. 60, nr 1

102--105

EN

The article presents one of the methods of construction verification connected with a designing process of the tilling-and-sowing combined machine. In the developed seeder a mechatronic control system was used which allows to increase the working speed and to increase the accuracy of sowing. Construction of the machine was elaborated and then its strength was analyzed. The calculations showed the effort of the construction and allowed to indicate areas with exceeded stress limits. It also allowed to make modifications in the construction at the designing stage. The next stage was fatigue strength analysis of the tilling-and-sowing combined machine carrying structure.

PL

W artykule przedstawiono jedną z metod weryfikacji konstrukcji związanej z projektowaniem agregatu uprawowo-siewnego. W opracowanym siewniku zastosowano mechatroniczny układ sterowania umożliwiający zwiększenie prędkości roboczej i podwyższenie dokładności wysiewu. Opracowano konstrukcję maszyny i poddano ją analizie wytrzymałościowej. Obliczenia te pokazały stan wytężenia konstrukcji i umożliwiły określenie obszarów przekroczenia dopuszczalnych naprężeń. Pozwoliło to na wprowadzenie zmian konstrukcyjnych na etapie projektowania maszyny. Następnym etapem pracy było przeprowadzenie analizy wytrzymałości zmęczeniowej konstrukcji nośnej agregatu

15

Analiza zmęczeniowa wciągarki suwnicy konsolowej z wykorzystaniem metody elementów skończonych

Śliwka J., Zielonka M.

Prace Naukowe Katedry Budowy Maszyn / Politechnika Śląska

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2014

|

nr 1

85--96

PL

W artykule przedstawiono obliczenia zmęczeniowych współczynników bezpieczeństwa wciągarki dla różnych grup natężenia pracy. Obliczenia wciągarki poprzedzono rozpoznawczymi analizami prostych próbek z karbem.

EN

The article presents the calculation of the fatigue safety factors winches for different groups of work intensity. Calculations winch were preceded by exploratory analysis of simple specimens with notch.

16

Inicjowanie pęknięć zmęczeniowych w blachownicowych belkach podsuwnicowych

Rykaluk K., Hotała E.

Materiały Budowlane

|

2014

|

nr 5

84--86

PL

Cykliczne obciążenie użytkowe belek podsuwnicowych, w kierunku pionowymi poziomym,ma rolę dominującą w obciążeniu ogólnym. Przy nieuniknionym narażeniu górnej strefy przekroju belki na skręcanie już po kilku latach eksploatacji mogą pojawić się podłużne pęknięcia środnika pod pasem górnym. Taki typ karbu nie jest sklasyfikowany w normach europejskich. W artykule podano warunki wystarczającej wytrzymałości środnika na inicjowanie pęknięć zmęczeniowych niskocyklowych.

EN

The cyclic working load of crane beams in vertical and horizontal direction constitutes a dominant role in the total load. For an inevitable exposure to torsion of the upper portion of the crosssection, after few years of operation, the longitudinal cracks of the web adjacent to the upper flange might appear. This type of notch is not classified in the European standards. The conditions of required strength of the web due to low-cycle fatigue crack initiations are given herein.

17

Analiza zmęczeniowa z zastosowaniem Metody Elementu Skończonego na przykładzie wysięgnika podnośnika stosowanego w Straży Pożarnej

Patyk R.

Logistyka

|

2014

|

nr 6

8437--8444

PL

W pracy przedstawiono przykład zastosowania Metody Elementu Skończonego do analiz procesu zmęczenia części na przykładzie wysięgnika podnośnika stosowanego w Straży Pożarnej. W ramach pracy pokrótce omówiono podstawę Metody Elementu Skończonego oraz zjawisko zużycia zmęczeniowego. Najważniejszą częścią pracy jest przedstawienie sposobu opracowywania modelu (fizycznego, matematycznego i komputerowego) oraz jego symulacja (tzn. rozwiązanie równania ruchu). Przedstawiono algorytm postępowania podczas rozwiązywania opracowanego modelu matematycznego za pomocą metody całkowania jawnego (explicit). Efektem pracy jest sprawdzenie poprawności konstrukcji ramienia wysięgnika podnośnika stosowanego w Straży Pożarnej. Konstrukcję sprawdzano w zakresie normy EN 1777:2010 w zakresie pkt. 5.2.5.3.3, gdzie według niego odporności na uszkodzenia spowodowane naprężeniami zmiennymi powinna wynosić 58 000 cykli. Po przeprowadzonych obliczeniach komputerowych stwierdzono, że analizowana konstrukcja spełnia wymagania normy.

EN

The paper presents an example of application of Finite Element Methods for the analysis of fatigue process on the basis of the lift boom used in the Fire Service. As part of the work briefly discussed Finite Element Methods basis and the phenomenon of fatigue wear. The most important part of the work is presentation the way of model(physical, mathematical and computer) developing and its simulation (i.e. the solution of the equation of motion). The paper presents the algorithm for solving a mathematical model using explicit integration method (explicit). The effect of this work is to check the correctness of the construction of boom lift arm used in the Fire Service. The construction was checked in terms of the standard EN 1777: 2010 in range of point 5.2.5.3.3, according to it immune damage caused by variable stresses should be 58 000 cycles. After conducting computer calculations, it was found that the analyzed construction meets the requirements of the standard.

18

The application of fuzzy logic in fatigue damage analysis

Muc A., Kędziora P.

Composites Theory and Practice

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2014

|

R. 14, nr 1

60--63

EN

In this study, fatigue damage progress is analyzed both theoretically and experimentally. Cyclic loading causes damage, reducing the strength until the material can no longer sustain even service loading. The theoretical analysis is associated with the definition of the damage parameter. The experimental analysis is mainly devoted to the consideration of two structural elements, i.e. a rectangular composite plate (made of glass fibre/epoxy resin) with a centrally located circular hole subjected to cyclic tensile stress and a square plate (made of aramid fiber/epoxy resin) subjected to shear loading. The experiments demonstrate scattering of the results. Fuzzy set analysis has been proposed in order to estimate the uncertainty in evaluation of the critical number of cycles corresponding to the final fatigue damage.

PL

Przedstawiono teoretyczną i eksperymentalną analizę rozwoju uszkodzeń zmęczeniowych. Cykliczne obciążenie powoduje uszkodzenia, co zmniejsza wytrzymałość aż do momentu, gdy materiał nie może przenosić nawet obciążenia eksploatacyjnego. Analiza teoretyczna jest związana z definicją tzw. parametru uszkodzeń. Badania dotyczą dwóch elementów konstrukcyjnych: prostokątnych kompozytowych płyt (wykonanych z włókna szklanego/żywicy epoksydowej) z centralnie umieszczonym kołowym otworem poddanych cyklicznemu rozciąganiu oraz kwadratowych płyt (wykonanych z włókna aramidowego/żywicy epoksydowej) poddanych ścinaniu. Eksperyment wykazuje znaczny rozrzut wyników. Zaproponowano zastosowanie teorii zbiorów rozmytych do oszacowania niepewności w ocenie krytycznej liczby cykli odpowiadającej zmęczeniowemu zniszczeniu.

19

Zastosowanie koncepcji najsłabszego ogniwa w obliczeniach trwałości zmęczeniowej stalowych złączy spawanych

Blacha Ł.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

|

2013

|

z. 102

9-12

EN

The results from the research on original idea of probabilistic approach to fatigue analysis of steel welded joints are gathered in this paper. Originality of the concept comes from the proposed definition of statistical paramaters in the Weibull distribution and application of the weakest link analysis. The exact values of such parameters were defined on the basis of experimental and simulation studies.

20

Wysokocyklowa analiza zmęczeniowa elementów osiowosymetrycznych

Wróbel I., Kóska M.

Mechanik

|

2013

|

R. 86, nr 2CD

PL

Przedmiotem analiz opisanych w prezentowanej pracy jest element osiowosymetryczny, koło zębate. Przedstawiono zbudowany do celu obliczeń model dyskretny z wykorzystaniem Metody Elementów Skończonych. Wykonano analizę statyczna modelu, której wyniki będą wejściowymi wartościami do wysokocyklowej analizy zmęczeniowej. Do celów przeprowadzenia analizy zmęczeniowej napisano program obliczeniowy w środowisku programowania Matlab. Zaprezentowano wyniki. Sformułowano wnioski.

EN

The object of the analysis described in the paper is axisymmetric element, gearshaft. Model for calculation, built based on the Finite Element Method for the analysis have been presented. The static analysis has been performed and the results from it has been input for high-cycle fatigue analysis. Dedicated program has been written in the development environment of Matlab program for high-cycle fatigue analysis. Results have been presented. The conclusions have been formulated.