{"title":"Isola in a linear one-degree-of-freedom feedback system with actuator rate saturation","authors":"Duc H. Nguyen, Thomas L. Hill, Mark H. Lowenberg","doi":"10.1002/msd2.12079","DOIUrl":"https://doi.org/10.1002/msd2.12079","url":null,"abstract":"<p>This short communication uses numerical continuation to highlight the existence of an isola in a simple one-degree-of-freedom harmonically forced feedback system with actuator rate limiting as its only nonlinear element. It was found that the isola (1) contains only rate-limited responses, (2) merges with the main branch when the forcing amplitude is sufficiently large, and (3) includes stable solutions that create a second attractor in regions where rate limiting is not expected. Furthermore, the isola is composed of two solutions for a given forcing frequency. These solutions have the same amplitudes in the state (pitch rate) projection; however, they have distinct phases, and their amplitudes are also distinct when projected onto the integrator state in the controller. The rich dynamics observed in such a simple example underlines the impact of rate limiting on feedback systems. Specifically, the combination of feedback and rate limiting can create detrimental dynamics that is hard to predict and requires careful analysis.</p>","PeriodicalId":60486,"journal":{"name":"国际机械系统动力学学报(英文)","volume":"3 3","pages":"186-191"},"PeriodicalIF":0.0,"publicationDate":"2023-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/msd2.12079","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50118716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Analytical modeling on the vibration response of a beam-stiffened Mindlin thick plate with free boundary conditions","authors":"Hui Guo, Kai Zhang","doi":"10.1002/msd2.12078","DOIUrl":"https://doi.org/10.1002/msd2.12078","url":null,"abstract":"<p>This paper presents a new analytical solution for the vibration response of a beam-stiffened Mindlin plate having a completely free boundary condition by utilizing a finite cosine integral transform. In the solution, the unknown coupling force and moments at the beam/plate interface and the unknown modal constants from the integral transform are determined by the continuity and compatibility conditions at the interface as well as the boundary conditions. It provides an easily implemented tool for exploring complex edge value problems for a class of higher-order partial differential equations represented by fully free-stiffened Mindlin thick plates. The validity of the model is evaluated by comparing the calculated free and forced vibration responses of the beam-stiffened plate with those calculated using a beam-stiffened thin plate and those from finite element analysis.</p>","PeriodicalId":60486,"journal":{"name":"国际机械系统动力学学报(英文)","volume":"3 2","pages":"119-126"},"PeriodicalIF":0.0,"publicationDate":"2023-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/msd2.12078","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50144609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Qi'ao Lei, Lei Yuan, Xin Yu, Yunyun Sun, Hongguang Li
{"title":"Experimental-based study of gear vibration characteristics incorporating the fractal topography of tooth surface","authors":"Qi'ao Lei, Lei Yuan, Xin Yu, Yunyun Sun, Hongguang Li","doi":"10.1002/msd2.12077","DOIUrl":"https://doi.org/10.1002/msd2.12077","url":null,"abstract":"<p>Microscopic roughness is inevitable on the gear meshing surface, which is also a key parameter affecting the dynamic response. The surface roughness exhibits self-affine characteristics across multiscales. To explore the influence of surface fractal topography on the vibration amplitude of the gear system under different rotational speeds and loads, an experimental setup of spur gear transmission is devised. The fractal dimension and fractal roughness of the meshing surface are calculated by the power spectral density method. The relationships between gear response and fractal parameters are revealed experimentally. Results indicate that a rougher tooth surface, that is, a smaller fractal dimension or larger fractal roughness, corresponds to an intense vibration amplitude. The sensitivity of dynamic response to the tooth surface topography varies at different rotational speeds and loads. Under low speed and light load conditions, the fractal dimension and fractal roughness have a more obvious influence on the dynamic response of the gear transmission system. With the increase of speed and load, the macroworking conditions gradually become the main factor attributed to vibration amplitude.</p>","PeriodicalId":60486,"journal":{"name":"国际机械系统动力学学报(英文)","volume":"3 2","pages":"173-182"},"PeriodicalIF":0.0,"publicationDate":"2023-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/msd2.12077","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50152071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jiancong Shi, Baoming Xu, Xinglong Wang, Jun Zhang
{"title":"A local spectrum enhancement-based method and its application in incipient fault diagnosis of rotating machinery","authors":"Jiancong Shi, Baoming Xu, Xinglong Wang, Jun Zhang","doi":"10.1002/msd2.12076","DOIUrl":"https://doi.org/10.1002/msd2.12076","url":null,"abstract":"<p>Incipient faults of gears and rolling bearings in rotating machineries are very difficult to identify using traditional envelope analysis methods. To address this challenge, this paper proposes an effective local spectrum enhancement-based diagnostic method that can identify weak fault frequencies in the original complicated raw signals. For this purpose, a traversal frequency band segmentation technique is first proposed for dividing the raw signal into a series of subfrequency bands. Then, the proposed synthetic quantitative index is constructed for selecting the most informative local frequency band (ILFB) containing fault features from the divided subfrequency bands. Furthermore, an improved grasshopper optimization algorithm-based stochastic resonance (SR) system is developed for enhancing weak fault features contained in the selected most ILFB with less computation cost. Finally, the enhanced weak fault frequencies are extracted from the output of the SR system using a common spectrum analysis. Two experiments on a laboratory planetary gearbox and an open bearing data set are used to verify the effectuality of the proposed method. The diagnostic results demonstrate that the proposed method can identify incipient faults of gears and bearings in an effective and accurate manner. Furthermore, the advantages of the proposed method are highlighted by comparison with other methods.</p>","PeriodicalId":60486,"journal":{"name":"国际机械系统动力学学报(英文)","volume":"3 2","pages":"162-172"},"PeriodicalIF":0.0,"publicationDate":"2023-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/msd2.12076","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50129731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mohamed I. A. Othman, Ebtesam E. M. Eraki, Mohamed F. Ismail
{"title":"Study of micro-elongated thermoelastic medium loaded with a piezoelectric layer under the influence of gravity using the dual-phase-lag model","authors":"Mohamed I. A. Othman, Ebtesam E. M. Eraki, Mohamed F. Ismail","doi":"10.1002/msd2.12075","DOIUrl":"https://doi.org/10.1002/msd2.12075","url":null,"abstract":"<p>This paper aims to examine the influence of gravity on a thermoelastic micro-elongated layer when a piezoelectric layer is above it, utilizing the theory of Lord–Shulman (L–S) and also the model of dual-phase-lag (DPL). A partial differential equation was transformed into an ordinary differential equation using the normal mode analysis. Aluminum epoxy numerical computations are carried out, and the results are presented in graphical format. The L–S theory and the model of DPL are compared in the presence and absence of gravity and it is found that gravity has quite a massive influence on all the physical quantities.</p>","PeriodicalId":60486,"journal":{"name":"国际机械系统动力学学报(英文)","volume":"3 2","pages":"136-145"},"PeriodicalIF":0.0,"publicationDate":"2023-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/msd2.12075","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50125225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Multiple control of thermoelectric dual-function metamaterials","authors":"Pengfei Zhuang, Jiping Huang","doi":"10.1002/msd2.12070","DOIUrl":"https://doi.org/10.1002/msd2.12070","url":null,"abstract":"<p>Thermal metamaterials based on transformation theory offer a practical design for controlling heat flow by engineering spatial distributions of material parameters, implementing interesting functions such as cloaking, concentrating, and rotating. However, most existing designs are limited to serving a single target function within a given physical domain. Here, we analytically prove the form invariance of thermoelectric (TE) governing equations, ensuring precise controls of the thermal flux and electric current. Then, we propose a dual-function metamaterial that can concentrate (or cloak) and rotate the TE field simultaneously. In addition, we introduce two practical control methods to realize corresponding functions: one is a temperature-switching TE rotating concentrator cloak that can switch between cloaking and concentrating; the other is an electrically controlled TE rotating concentrator that can handle the temperature field precisely by adjusting external voltages. The theoretical predictions and finite-element simulations agree well with each other. This work provides a unified framework for manipulating the direction and density of the TE field simultaneously and may contribute to the study of thermal management, such as thermal rectification and thermal diodes.</p>","PeriodicalId":60486,"journal":{"name":"国际机械系统动力学学报(英文)","volume":"3 2","pages":"127-135"},"PeriodicalIF":0.0,"publicationDate":"2023-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/msd2.12070","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50130416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sansan Ding, Peter Eberhard, Georg Schneider, Patrick Schmid, Arnim Kargl, Yong Cui, Ullrich Martin, Xin Liang, Chao Huang, Markus Bauer, Florian Dignath, Qinghua Zheng
{"title":"Development of new electromagnetic suspension–based high-speed Maglev vehicles in China: Historical and recent progress in the field of dynamical simulation","authors":"Sansan Ding, Peter Eberhard, Georg Schneider, Patrick Schmid, Arnim Kargl, Yong Cui, Ullrich Martin, Xin Liang, Chao Huang, Markus Bauer, Florian Dignath, Qinghua Zheng","doi":"10.1002/msd2.12069","DOIUrl":"https://doi.org/10.1002/msd2.12069","url":null,"abstract":"<p>High-speed Maglev is a cutting-edge technology brought back into the focus of research by plans of the Chinese government for the development of a new 600 km/h Maglev train. A Chinese-German cooperation with industrial and academic partners has been established to pursue this ambitious goal and bring together experts from multiple disciplines. This contribution presents the joint work and achievements of CRRC Qingdao Sifang, thyssenkrupp Transrapid, CDFEB, and the ITM of the University of Stuttgart, regarding research and development in the field of high-speed Maglev systems. Furthermore, an overview is given of the historical development of the Transrapid in Germany, the associated development of dynamical simulation models, and recent developments regarding high-speed Maglev trains in China.</p>","PeriodicalId":60486,"journal":{"name":"国际机械系统动力学学报(英文)","volume":"3 2","pages":"97-118"},"PeriodicalIF":0.0,"publicationDate":"2023-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/msd2.12069","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50144980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Harry J. Carpenter, Mergen H. Ghayesh, Anthony C. Zander, Peter J. Psaltis
{"title":"Effect of coronary artery dynamics on the wall shear stress vector field topological skeleton in fluid–structure interaction analyses","authors":"Harry J. Carpenter, Mergen H. Ghayesh, Anthony C. Zander, Peter J. Psaltis","doi":"10.1002/msd2.12068","DOIUrl":"https://doi.org/10.1002/msd2.12068","url":null,"abstract":"<p>In this paper, we investigate the impact of coronary artery dynamics on the wall shear stress (WSS) vector field topology by comparing fluid–structure interaction (FSI) and computational fluid dynamics (CFD) techniques. As one of the most common causes of death globally, coronary artery disease (CAD) is a significant economic burden; however, novel approaches are still needed to improve our ability to predict its progression. FSI can include the unique dynamical factors present in the coronary vasculature. To investigate the impact of these dynamical factors, we study an idealized artery model with sequential stenosis. The transient simulations made use of the hyperelastic artery and lipid constitutive equations, non-Newtonian blood viscosity, and the characteristic out-of-phase pressure and velocity distribution of the left anterior descending coronary artery. We compare changes to established metrics of time-averaged WSS (TAWSS) and the oscillatory shear index (OSI) to changes in the emerging WSS divergence, calculated here in a modified version to handle the deforming mesh of FSI simulations. Results suggest that the motion of the artery can impact downstream patterns in both divergence and OSI. WSS magnitude is also decreased by up to 57% due to motion in some regions. WSS divergence patterns varied most significantly between simulations over the systolic period, the time of the largest displacements. This investigation highlights that coronary dynamics could impact markers of potential CAD progression and warrants further detailed investigations in more diverse geometries and patient cases.</p>","PeriodicalId":60486,"journal":{"name":"国际机械系统动力学学报(英文)","volume":"3 1","pages":"48-57"},"PeriodicalIF":0.0,"publicationDate":"2023-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/msd2.12068","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50135224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yexiong Huang, Enmin Chen, Jialiang Sun, Dongping Jin
{"title":"Wave control of a flexible space tether based on elastic metamaterials","authors":"Yexiong Huang, Enmin Chen, Jialiang Sun, Dongping Jin","doi":"10.1002/msd2.12067","DOIUrl":"https://doi.org/10.1002/msd2.12067","url":null,"abstract":"<p>This study proposes a spider-web elastic metamaterial to suppress vibrations in space slender structures, such as flexible space tethers. The metamaterial consists of unit cells that are periodically distributed on the space tether to obtain band gaps. The finite element model of the unit cell is established by employing the absolute nodal coordinate formulation (ANCF) due to the large deformation of the structure. The eigenfrequencies and corresponding vibration modes of the unit cell are obtained by ANCF. Moreover, the band gap of the unit cell is calculated based on the phonon crystal theory. The relationship between the vibration modes and the band gaps is analyzed. Finally, an experiment is conducted to verify the vibration transmission characteristics of finite period cells. The results show the effectiveness of the spider-web elastic metamaterial for vibration suppression of a flexible tether. This study provides insights into the use of elastic metamaterials for vibration isolation in space tether systems.</p>","PeriodicalId":60486,"journal":{"name":"国际机械系统动力学学报(英文)","volume":"3 1","pages":"58-72"},"PeriodicalIF":0.0,"publicationDate":"2023-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/msd2.12067","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50135225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maria I. Katsidoniotaki, Ioannis Petromichelakis, Ioannis A. Kougioumtzoglou
{"title":"Nonlinear stochastic dynamics of an array of coupled micromechanical oscillators","authors":"Maria I. Katsidoniotaki, Ioannis Petromichelakis, Ioannis A. Kougioumtzoglou","doi":"10.1002/msd2.12066","DOIUrl":"https://doi.org/10.1002/msd2.12066","url":null,"abstract":"<p>The stochastic response of a multi-degree-of-freedom nonlinear dynamical system is determined based on the recently developed Wiener path integral (WPI) technique. The system can be construed as a representative model of electrostatically coupled arrays of micromechanical oscillators, and relates to an experiment performed by Buks and Roukes. Compared to alternative modeling and solution treatments in the literature, the paper exhibits the following novelties. First, typically adopted linear, or higher-order polynomial, approximations of the nonlinear electrostatic forces are circumvented. Second, for the first time, stochastic modeling is employed by considering a random excitation component representing the effect of diverse noise sources on the system dynamics. Third, the resulting high-dimensional, nonlinear system of coupled stochastic differential equations governing the dynamics of the micromechanical array is solved based on the WPI technique for determining the response joint probability density function. Comparisons with pertinent Monte Carlo simulation data demonstrate a quite high degree of accuracy and computational efficiency exhibited by the WPI technique. Further, it is shown that the proposed model can capture, at least in a qualitative manner, the salient aspects of the frequency domain response of the associated experimental setup.</p>","PeriodicalId":60486,"journal":{"name":"国际机械系统动力学学报(英文)","volume":"3 1","pages":"3-11"},"PeriodicalIF":0.0,"publicationDate":"2023-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/msd2.12066","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50131801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}