Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB)最新文献_第2页

On the Mechanical Behaviour in Stiffness Compensated Piezoelectric Beams - An Experimental Investigation Towards Energy Harvesting 刚度补偿压电梁的力学性能研究——能量收集的实验研究

Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB) Pub Date : 2021-08-17 DOI: 10.1115/detc2021-68922

E. van de Wetering, T. Blad, R. V. van Ostayen

引用次数: 0

Combined Coulomb and Viscous Damping Estimation Using Topological Signal Processing 基于拓扑信号处理的库仑和粘性阻尼组合估计

Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB) Pub Date : 2021-08-17 DOI: 10.1115/detc2021-68456

Audun D. Myers, Firas A. Khasawneh

{"title":"Combined Coulomb and Viscous Damping Estimation Using Topological Signal Processing","authors":"Audun D. Myers, Firas A. Khasawneh","doi":"10.1115/detc2021-68456","DOIUrl":"https://doi.org/10.1115/detc2021-68456","url":null,"abstract":"\u0000 In this work we develop a novel time-domain approach for the simultaneous estimation of the damping parameters for a single degree of freedom oscillator with both viscous and coulomb damping. Our approach leverages zero-dimensional sublevel set persistence — a tool from Topological Signal Processing (TSP) — to analyze the ring down vibration of the signal. Sublevel set persistence is used as it alleviates the need for peak selection when analyzing the time-domain of the signal and provides an alternative noise-robust method for visualizing the damping envelope. We are able to successfully estimate the damping parameters using both a direct approach and a function fitting method. We show that the direct approach is only appropriate for low levels of additive noise, but allows for a less computationally demanding estimation of the parameters. Alternatively, the function fitting method provides accurate estimates for significantly higher levels of additive noise. The results are provided through a numerically simulated example with mixed coulomb and viscous damping. We demonstrate the robustness of our method for accurately estimating both damping parameters for various levels of additive noise, a wide range of sampling frequencies, and both high and low levels of damping. This analysis includes providing suggested limitations of the method when applied to real-world signals.","PeriodicalId":425665,"journal":{"name":"Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131076555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical Analysis and Parameter Optimization of a Portable Two-Body Attenuator Wave Energy Converter 便携式两体衰减波能变换器的数值分析与参数优化

Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB) Pub Date : 2021-08-17 DOI: 10.1115/detc2021-69977

J. Capper, J. Mi, Qiaofeng Li, L. Zuo

{"title":"Numerical Analysis and Parameter Optimization of a Portable Two-Body Attenuator Wave Energy Converter","authors":"J. Capper, J. Mi, Qiaofeng Li, L. Zuo","doi":"10.1115/detc2021-69977","DOIUrl":"https://doi.org/10.1115/detc2021-69977","url":null,"abstract":"\u0000 Easily portable, small-sized ocean wave energy converters (WECs) may be used in many situations where large-sized WEC devices are not necessary or practical. Power maximization for small-sized WECs amplifies challenges that are not as difficult with large-sized devices, especially tuning the device’s natural frequency to match the wave frequency and achieve resonance. In this study, power maximization is performed for a small-sized, two-body attenuator WEC with a footprint constraint of about 1m. A thin, submerged tuning plate is added to each body to increase added mass without significantly increasing hydrostatic stiffness in order to reach resonance. Three different body cross-section geometries are analyzed. Device power absorption is determined through time domain simulations using WEC-Sim with a simplified two-degree-of-freedom (2DOF) model and a more realistic three-degree-of-freedom (3DOF) model. Different drag coefficients are used for each geometry to explore the effect of drag. A mooring stiffness study is performed with the 3DOF model to investigate the mooring impact. Based on the 2DOF and 3DOF power results, there is not a significant difference in power between the shapes if the same drag coefficient is used, but the elliptical shape has the highest power after assigning a different approximate drag coefficient to each shape. The mooring stiffness study shows that mooring stiffness can be increased in order to increase relative motion between the two bodies and consequently increase the power.","PeriodicalId":425665,"journal":{"name":"Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129684711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Health Monitoring Using Acoustic Emission Technique During Fused Filament Fabrication Printing Process 用声发射技术监测熔丝制造印刷过程中的健康状况

Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB) Pub Date : 2021-08-17 DOI: 10.1115/detc2021-70585

Ke Xu, S. Manoochehri

{"title":"Health Monitoring Using Acoustic Emission Technique During Fused Filament Fabrication Printing Process","authors":"Ke Xu, S. Manoochehri","doi":"10.1115/detc2021-70585","DOIUrl":"https://doi.org/10.1115/detc2021-70585","url":null,"abstract":"\u0000 Fused Filament Fabrication (FFF) is one of the most popular additive manufacturing technologies for manufacturing prototypes with various complex geometries. However, current commercial FFF machines have limitations in terms of process reliability and product quality. In order to overcome these limitations and improve the accuracy and reliability of these machines, a real-time monitoring system is needed to make sure that any part defects can be detected during the printing process and printing parameters can be identified that can be modified to resolve the printing anomalies resulting in minimization of waste and improvement of efficiency. In this study, a method for in-situ monitoring of FFF machine conditions is proposed utilizing an acoustic emission (AE) technology. The AE sensor is used to monitor the vibration signals generated during the whole printing process in real-time. The AE signal is then analyzed and processed, and categorized according to the selected objective characteristics. The proposed method can be utilized to identify the abnormal states of machine conditions. The time-domain features of AE hits after post-processing are used as key indicators. Experimental results show that this method has the potential to be used as a non-invasive diagnostic and prognostic tool for FFF machine maintenance and process control.","PeriodicalId":425665,"journal":{"name":"Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127870858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Non-Synchronous Vibration and Lock-in Regimes in Coupled Structures Using Reduced Models 基于简化模型的耦合结构非同步振动和锁定状态

Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB) Pub Date : 2021-08-17 DOI: 10.1115/detc2021-66815

M. Byrtus, Š. Dyk, M. Hajžman

引用次数: 0

Negative Refractive Index in a Two-Dimensional Nonlinear Rotator Lattice 二维非线性旋转晶格的负折射率

Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB) Pub Date : 2021-08-17 DOI: 10.1115/detc2021-71840

Lezheng Fang, M. Leamy

{"title":"Negative Refractive Index in a Two-Dimensional Nonlinear Rotator Lattice","authors":"Lezheng Fang, M. Leamy","doi":"10.1115/detc2021-71840","DOIUrl":"https://doi.org/10.1115/detc2021-71840","url":null,"abstract":"\u0000 Acoustic metamaterials achieving negative index refraction usually operate linearly over a narrowband of frequency and consist of complex unit cell structures incorporating resonators. In this paper, we propose and analyze a simple, non-resonant, nonlinear rotator lattice structure which can be configured with either a positive or negative index of refraction over a broadband frequency range. The system’s frequency-dependent transmission is studied analytically via a reduced model along the interface of positive and negative refractive index lattices. Results for energy transmission are compared to those obtained using direct numerical simulation and close agreement is documented for small amplitude waves. For larger amplitude waves, a multiple scales analysis approach is used to show that the nonlinearity of the lattice shifts the system’s band structure, inducing amplitude-dependent transmission. For the studied system, the transmission decreases as we increase the incident wave amplitude, agreeing qualitatively with results from direct numerical simulation. At large-enough amplitudes, near the interface the wave amplitude decreases rapidly. As the wave travels further into the media, the amplitude drops, causing the nonlinear effect to decline as well. This decaying envelope does not result in a zero transmission in the far field, as expected from linear theory, and instead, the nonlinearity of the proposed rotator lattice prevents the far-field transmitted wave from surpassing a specific threshold amplitude, regardless of the incident wave. This finding may serve as an inspiration for designing nonlinear wave saturators.","PeriodicalId":425665,"journal":{"name":"Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126398733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Design of Band Gap Formation in Periodic Rotors via Optimization 周期转子带隙形成的优化设计

Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB) Pub Date : 2021-08-17 DOI: 10.1115/detc2021-70405

P. B. Lamas, R. Nicoletti

引用次数: 0

Reduction of Whole Body Vibration in a Wide Frequency Range Using Inflation Pressure Control of Air Bladder Cushion 气囊垫充气压力控制在大频率范围内降低全身振动

Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB) Pub Date : 2021-08-17 DOI: 10.1115/detc2021-71374

Pavan Nuthi, Y. Gu, Aida Nasirian, A. R. Lindsay, Himanshu Purandare, Nischita Haldipurkar, Kashish Shah, M. Wijesundara

{"title":"Reduction of Whole Body Vibration in a Wide Frequency Range Using Inflation Pressure Control of Air Bladder Cushion","authors":"Pavan Nuthi, Y. Gu, Aida Nasirian, A. R. Lindsay, Himanshu Purandare, Nischita Haldipurkar, Kashish Shah, M. Wijesundara","doi":"10.1115/detc2021-71374","DOIUrl":"https://doi.org/10.1115/detc2021-71374","url":null,"abstract":"\u0000 Several types of interfaces like foam and inflated air cells exist to reduce the effect of mechanical vibration experienced in human-machine interfaces in different scenarios such as transportation. However, their vibration attenuation performance in a wide frequency range relevant to whole body vibration (1–80 Hz) leaves much to be desired. In this study, we investigate the effect of inflation pressure on the vibration attenuation behavior of an air cell cushion. An experimental setup capable of conducting frequency sweep tests and regulating inflation pressure in an air cell array cushion was developed. Frequency sweep tests were conducted at various inflations and the vibration transmissibilities at static inflations were plotted. A dynamic inflation scheme was developed based on the apriori knowledge of inflation dependent transmissibilities. Furthermore, the closed loop behavior of the inflation scheme was evaluated with a frequency sweep test. The resulting closed loop transmissibility indicated better vibration attenuation performance than any single static inflation for the air cell array cushion in the range of frequencies relevant to whole body vibration. This result lays the groundwork for potential air cell cushions which modify their inflation dynamically through a direct feedback from sensors like accelerometers to attenuate vibration in a wide frequency range.","PeriodicalId":425665,"journal":{"name":"Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127819087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Vibration Characteristics of 3D Printed Viscoelastic Graded Polymeric Plates 3D打印粘弹性梯度聚合物板的振动特性

Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB) Pub Date : 2021-08-17 DOI: 10.1115/detc2021-68460

J. Carter, K. Singh, Fazeel Khan

{"title":"Vibration Characteristics of 3D Printed Viscoelastic Graded Polymeric Plates","authors":"J. Carter, K. Singh, Fazeel Khan","doi":"10.1115/detc2021-68460","DOIUrl":"https://doi.org/10.1115/detc2021-68460","url":null,"abstract":"\u0000 The exploration of structures made of multiple materials is a growing area of research as additive manufacturing processing technologies such as fused deposition modeling (FDM) 3D printing allows for their fabrication. Such a technology allows for rapid prototyping of structural components with complex geometries or spatially distributed materials with different properties and functionalities. By selecting suitable spatial distribution of materials, the performance of structural components can be manipulated and enhanced as per different engineering application needs. For a low-cost design of structural prototypes using 3D printing processes, viscoelastic polymeric materials are often used, having inherent damping properties. In this research, vibration characteristics of thin plates which are axially graded with multiple polymeric materials are investigated. The goal is to understand the influence of material grading on the frequency and damping characteristics of graded plates. Although in literature, material grading along the thickness in designing composite laminates and their vibration characteristics are available, the performance of plates having axially graded viscoelastic polymers have not been investigated yet. Through systematic modeling and experimental plans, vibration characteristics of axially graded viscoelastic plates are presented here. In particular, the damping performance for different grading schemes is evaluated. It is anticipated that such analysis will allow accurate modeling and testing of design prototypes of structural components for future research, such as design and testing of graded panels for enhanced flutter characteristics.","PeriodicalId":425665,"journal":{"name":"Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB)","volume":"8 1-2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132463927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Guidelines for Optimizing the Error in Area Ratio Damping Estimation Method 面积比阻尼估计方法误差优化指南

Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB) Pub Date : 2021-08-17 DOI: 10.1115/detc2021-70590

Balija Santoshkumar, Firas A. Khasawneh

{"title":"Guidelines for Optimizing the Error in Area Ratio Damping Estimation Method","authors":"Balija Santoshkumar, Firas A. Khasawneh","doi":"10.1115/detc2021-70590","DOIUrl":"https://doi.org/10.1115/detc2021-70590","url":null,"abstract":"\u0000 The logarithmic decrement (log-dec) is one of the most popular methods for viscous damping estimation in linear, single degree of freedom systems. It estimates the damping ratio by examining the decay in the amplitude between two peaks some number of cycles apart. The accuracy in the estimation is sensitive to the chosen number of cycles, where the latter can be optimized such that the uncertainty in the estimation is minimized. However, the log-dec method is not suitable for systems with high damping ratios (approximately > 0.3). Another recent approach for damping estimation is based on considering a ratio of the amplitudes of the positive and negative areas in the free response of the oscillator. Although prior works on the areas method only tested lightly damped systems, we show here that — in contrast to log-dec — this approach can estimate the damping ratio over the whole range of underdamped linear oscillators. However, in contrast to log-dec, there are no available guidelines on how many areas to include in the damping estimation. In this work, we derive uncertainty analysis expressions for the areas method and we utilize them to obtain the optimal number of areas to use. Our results show that for a very low damping ratio (< 0.01), choosing more than two areas in the estimation increases the uncertainty. In contrast, for moderate to high damping (between 0.05 and 1), we need to consider all the available areas in the estimation. One caveat in the range of high damping (between 0.3 and 1) is that while it is desirable to include all the available areas, uncertainty increases when considering up to 3 areas. Therefore, if only 4 areas are available in this range, then to reduce the uncertainty in the estimate only the first two areas must be considered. The results are verified using a large number of numerical simulations including different levels of noise.","PeriodicalId":425665,"journal":{"name":"Volume 10: 33rd Conference on Mechanical Vibration and Sound (VIB)","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124209980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2