Smart structures and materials. Nondestructive evaluation for health monitoring and diagnostics最新文献

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On the modeling and optimization of an electromagnetic energy harvester 电磁能量采集器的建模与优化
Airton José Schmitt, J. Cordioli, D. Braga, M. V. Ferreira da Luz
{"title":"On the modeling and optimization of an electromagnetic energy harvester","authors":"Airton José Schmitt, J. Cordioli, D. Braga, M. V. Ferreira da Luz","doi":"10.1117/12.2658581","DOIUrl":"https://doi.org/10.1117/12.2658581","url":null,"abstract":"The interest in modeling and prototyping the so-called Vibration Energy Harvesters (VEHs) has increased significantly in the last decades, given the growing demand for energy sources that can capture energy from the vibration of a machine, for example, to power small sensors and vibration monitoring devices. In this work, the design and optimization of a commercial Electromagnetic Vibration Energy Harvester (EMVEH) are presented. Such a device contains in its interior a resonant-type electromagnetic transducer, the latter composed basically by a seismic mass, a mechanical spring and a multi-turn coil. The complete set weighs about 90 g and occupies a total volume of approximately 50.97 cm3, being able to generate up 45mW at its resonance frequency of 60 Hz, with a bandwidth of 2.5 Hz. Furthermore, the linear generator presented in this paper reaches a maximum Normalized Power Density (NPD) of 1.8018mW/(cm3g2) at an acceleration amplitude of 0.7 g (∼ 6.67m/s2). To proceed with electromechanical modeling and further optimization, a numerical model was developed via commercial software COMSOL Multiphysics, from which it was possible to optimize its geometry in order to maximize its NPD and power output. A Surrogate optimization algorithm was then implemented in MATLAB, in which both volume and mechanical stress were considered as project constraints.","PeriodicalId":89272,"journal":{"name":"Smart structures and materials. Nondestructive evaluation for health monitoring and diagnostics","volume":"12 1","pages":"124831P - 124831P-6"},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82888068","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 a lightweight SMA driven parallel gripper for collaborative robots 协作机器人轻量化SMA驱动并联夹持器设计
D. Scholtes, Stefan Seelecke, Paul Motzki
{"title":"Design of a lightweight SMA driven parallel gripper for collaborative robots","authors":"D. Scholtes, Stefan Seelecke, Paul Motzki","doi":"10.1117/12.2658402","DOIUrl":"https://doi.org/10.1117/12.2658402","url":null,"abstract":"For a given use case of a collaborative assembly station, a gripper is needed that can handle workpieces with varying geometries. Existing electric robotic grippers are heavy and expensive, while pneumatic alternatives are noisy, inefficient and need stiff tubes and additional valves. A gripper driven by shape memory alloys (SMA) is by design silent and lightweight, purely electric, can be controlled in an energy efficient way and is predestined for collaborative applications due to the soft actuator behavior. The challenges of the development of such a system are given by the requirements for the use case at hand. They are jaw opening stroke and high forces combined with a short cycle time. In this paper the design process of a normally closed parallel gripper prototype driven by SMA wires featuring 14 N maximum gripping force and 30 mm opening stroke is discussed. Thin NiTi wires with a diameter of 76 μm are used to ensure a fast cooling. With this measure a cycle time of 1 second and below can be reached. A two-stage telescopic mechanism having overall 96 wires in parallel drives the gripper jaws by means of a lever mechanics. The power consumption is around 48 W and the gripper is designed to work with the electrical industry low voltage standard of 24 V and 2 A.","PeriodicalId":89272,"journal":{"name":"Smart structures and materials. Nondestructive evaluation for health monitoring and diagnostics","volume":"95 1","pages":"124830K - 124830K-6"},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78082874","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
Dynamic data physicalization by unimorph dielectric elastomer actuators 均匀介质弹性体致动器的动态数据物理化
Michael Gareis, Ozan Çabuk, J. Maas
{"title":"Dynamic data physicalization by unimorph dielectric elastomer actuators","authors":"Michael Gareis, Ozan Çabuk, J. Maas","doi":"10.1117/12.2661518","DOIUrl":"https://doi.org/10.1117/12.2661518","url":null,"abstract":"Physicalization helps the user understand complex data intuitively. Especially when confronted with complex, multidimensional datasets as in the smart home environment, classic graphical user interfaces struggle to visualize data in a way compatible with the paradigm of Calm Technology and new means of displaying data need to be explored, to decrease the cognitive burden on the user. Shape changing interfaces (SCI) using smart materials can change their appearance under electrical stimuli and provide the means to physicalize the data found in the smart home from sensors, appliances or others. Within the scope of this work, a smart display using dielectric elastomer unimorph actuators (UDEA) is developed, which can be used to explore how dielectric elastomers (DE) can be used for an SCI. A dynamic model of previous work has been adapted to the updated geometry. Reproducible production of the actuators is one focus of the current work. A novel sheet-to-sheet process for manufacturing multilayer DE-laminates is presented. Manual processing of the laminates to actuators is described and effects of human error on actuator performance in this process is assessed and found to be low to ensure reproducible fabrication. Finally the system design is presented and discussed. The developed display allows controlling 15 independent shape changing devices and will allow to gain more knowledge about physicalization of data using DE actuators.","PeriodicalId":89272,"journal":{"name":"Smart structures and materials. Nondestructive evaluation for health monitoring and diagnostics","volume":"4 1","pages":"1248203 - 1248203-10"},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81902742","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
Rotary piezoelectric motor using a rectangular vibrator of four actuators 旋转压电电机采用一个矩形振子的四个作动器
Hsuan-Jung Chen, Y. Hsu, Chih-Kung Lee
{"title":"Rotary piezoelectric motor using a rectangular vibrator of four actuators","authors":"Hsuan-Jung Chen, Y. Hsu, Chih-Kung Lee","doi":"10.1117/12.2658219","DOIUrl":"https://doi.org/10.1117/12.2658219","url":null,"abstract":"Piezoelectric rotary motors have become the standard motor for rotational motorization. However, due to its complex structure and operational mechanism, its cost is considerably high. To reduce the complexity and cost of piezoelectric rotary motors, we developed a new type of motor driven by traveling waves. It is constructed of a rectangular stainlesssteel plate and four piezoelectric actuators. To generate a rotational traveling wave on a rectangular plate, two higherorder bending modes are stimulated to generate rotational traveling waves propagating in a diamond-shaped trajectory. The dimension of the stainless-steel plate and four piezoelectric PZT plates attached to its surface. The boundary conditions are chosen to be simply supported in the x-direction and free-edge in the y-direction, and an analytical model is derived for analyzing its vibration profile. To stimulate the rotational traveling waves, the Φ34 and Φ43 bending modes are chosen. The dimension of the stainless-steel plate was designed, and the resonant frequencies are close to each other at 2.733kHz and 2.781kHz. Using this design, both bending modes are simultaneously excited with a single driving frequency at 2.757kHz. The combined Φ34 and Φ43 bending modes became a steady rotary traveling wave, and it can be used to drive a rotary starter. It is also found that the vibration performance could be optimized by modulating the phase difference and voltage ratio between the Φ34 and Φ43 bending modes. Finally, the driving method of this piezoelectric rotary motor is experimentally verified and compared with the analytical model.","PeriodicalId":89272,"journal":{"name":"Smart structures and materials. Nondestructive evaluation for health monitoring and diagnostics","volume":"16 1","pages":"124831L - 124831L-8"},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84332660","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
Discontinuous refractive index in metamaterial study 超材料研究中的不连续折射率
Wei-Chih Wang, A. Wegrowski, C. Tsui
{"title":"Discontinuous refractive index in metamaterial study","authors":"Wei-Chih Wang, A. Wegrowski, C. Tsui","doi":"10.1117/12.2664902","DOIUrl":"https://doi.org/10.1117/12.2664902","url":null,"abstract":"This paper proposes a geometrical method to determine ambiguity that arises in metamaterials that displays discontinuity in refractive index in the frequency spectrum. Three cases of such metamaterial designs presented in literatures are investigated using the proposed method. First, numerical simulations of the three metamaterial designs are performed to extract the device parameters across the frequency spectrum and the results are compared with the reported results. Then, we investigate the refractive index discontinuity geometrically using a numerical simulation of a prism consists of the metamaterial unit cell excited by an electromagnetic plane wave. The prism simulation will allow us to confirm the refractive index discontinuity by observing the electromagnetic wave propagation at the output of the prism across the frequency spectrum of interest and determine whether the refractive index become negative at the discontinuity. Finally, the phase of an incident electromagnetic wave across the metamaterial are observed at the frequencies where the refractive index crosses over into the negative region at the discontinuities to investigate the physical behavior of the wave within and outside the boundary of the metamaterial.","PeriodicalId":89272,"journal":{"name":"Smart structures and materials. Nondestructive evaluation for health monitoring and diagnostics","volume":"44 1","pages":"124830J - 124830J-13"},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83707603","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
Effect of piezoelectric material nonlinearity on vibration-based piezoelectric energy harvesting 压电材料非线性对基于振动的压电能量收集的影响
Yabin Liao, Chunbo Lan, Feng Qian, L. Zuo
{"title":"Effect of piezoelectric material nonlinearity on vibration-based piezoelectric energy harvesting","authors":"Yabin Liao, Chunbo Lan, Feng Qian, L. Zuo","doi":"10.1117/12.2657404","DOIUrl":"https://doi.org/10.1117/12.2657404","url":null,"abstract":"Vibration-based piezoelectric energy harvester (VPEH) has received significant interests in the last couple of decades. In recent years, more emphasis has been given to the understanding and modeling the effect of nonlinearities introduced by mechanical and electrical aspects of the system, while the nonlinearity induced by the piezoelectric material is usually ignored. However, it has been experimentally found that this material nonlinearity can have a significant effect on the system behavior even at low to moderate excitation level. This paper is motivated to consider this piezoelectric nonlinearity in the system model, and study how the nonlinearity affects the power characteristics of the system, most importantly, the power limit and electromechanical coupling. Through a harmonic balance analysis, an approximated model is developed from a nonlinear model proposed in the literature, and allows for deriving closed-form expressions of important power characteristics. The approximated model elucidates the effect of piezoelectric material nonlinearity, which is represented by a nonlinear damping term and a nonlinear stiffness term. It is revealed that the addition of piezoelectric material nonlinearity results in interesting power behaviors that are largely different from that of a VPEH without piezoelectric nonlinearity. For instance, the power limit is reduced by the nonlinear damping induced by the piezoelectric nonlinearity. In addition, the critical electrical coupling, also known as the minimum electromechanical coupling for the system to possible reach the power limit, increases with the base excitation. A strongly coupled VPEH with piezoelectric nonlinearity under low excitation could become weakly coupled under large excitation.","PeriodicalId":89272,"journal":{"name":"Smart structures and materials. Nondestructive evaluation for health monitoring and diagnostics","volume":"8 1","pages":"124830V - 124830V-15"},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82509906","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
Influence of the active-to-passive area ratio on the electrically induced strain of a fiber-reinforced dielectric elastomer actuator 主动被动面积比对纤维增强介电弹性体作动器电致应变的影响
H. Liebscher, Anett Endesfelder, Markus Koenigsdorff, J. Mersch, M. Zimmermann, G. Gerlach
{"title":"Influence of the active-to-passive area ratio on the electrically induced strain of a fiber-reinforced dielectric elastomer actuator","authors":"H. Liebscher, Anett Endesfelder, Markus Koenigsdorff, J. Mersch, M. Zimmermann, G. Gerlach","doi":"10.1117/12.2656662","DOIUrl":"https://doi.org/10.1117/12.2656662","url":null,"abstract":"There is an increasing interest to use novel elastomers with inherent or modified advanced dielectric and mechanical properties, as components of dielectric elastomer actuators (DEA). This requires corresponding techniques to assess their electromechanical performance. One performance criterion is the electrically induced deformation of the active electrode area. In this work, a rectangular DEA is used to investigate the influence of the ratio between the active electrode and the passive area on the actuator deformation. For this purpose, a dielectric silicone film is bonded on one surface to a unidirectional carbon fiber fabric. Thereby, highly anisotropic mechanical properties are implemented. When strains are applied perpendicular to the fiber direction, the composite hardly contracts in the fiber direction due to the superior stiffness of the fibers. In addition, the conductive fiber structure also acts as a highly anisotropic compliant electrode. By application of a second paste-like electrode onto the silicone film a DEA is created that operates in a pure shear configuration. This assembly enables the modification of the active-to-passive area ratio and the investigation of its effect on the actuator deformation. Image-based measurements are used to determine the strain of the active electrode area. The experimental results are compared to a lumped-parameter model that considers the electromechanical properties of the fiber-reinforced DEA. In summary, the ratio of the active-to-passive area has a significant influence on the measured deformation. Especially for novel actuator materials that do not exhibit large strains, an active-to-passive ratio of 50 % proves to be particularly advantageous.","PeriodicalId":89272,"journal":{"name":"Smart structures and materials. Nondestructive evaluation for health monitoring and diagnostics","volume":"165 1","pages":"124820S - 124820S-8"},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80440083","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
Low profile dielectric elastomer actuator system with unibody compliant joint transmission 低轮廓介质弹性体驱动器系统与一体柔性关节传动
D. Bruch, I. Naumov, T. Willian, Paul Motzki, S. Seelecke
{"title":"Low profile dielectric elastomer actuator system with unibody compliant joint transmission","authors":"D. Bruch, I. Naumov, T. Willian, Paul Motzki, S. Seelecke","doi":"10.1117/12.2658448","DOIUrl":"https://doi.org/10.1117/12.2658448","url":null,"abstract":"Dielectric Elastomer Actuators (DEAs) are known for their outstanding properties such as low weight, high energy density and self-sensing capability. Compared to conventional magnetic actuators, they are manufactured from generally inexpensive and widely available polymer materials, making the technology particularly attractive for developing actuator systems that are potentially low-cost and serve a wide range of applications. This advantage can be further enhanced by developing scalable and standardized system designs that use identical parts in order to reduce product variation and enable high volumes in a mass production process. Following this approach, this paper introduces a low-profile and compact linear actuator design, which provides a configurable force and stroke transmission in order to serve different load-profiles without changing shape and dimension of the DEA itself. The design is based on rectangular-shaped, in-plane operating DEAs coupled to a unibody linkage mechanism, which is likewise flat and based on compliant joints and rigid links. A negative rate stiffness mechanism enables to increase the performance output of the actuator system in terms of cyclic converted energy in quasi-static operation. By configuring the lever ratios of the input and output sides accordingly, it can either behave stroke-magnifying or force-magnifying. Thus, as an example, a system with negative and one with positive transmission ratio are realized and characterized with respect to their force and their stroke behavior.","PeriodicalId":89272,"journal":{"name":"Smart structures and materials. Nondestructive evaluation for health monitoring and diagnostics","volume":"118 1","pages":"1248207 - 1248207-9"},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81373937","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
Isotropic hybrid architected foams with enhanced energy absorption 具有增强能量吸收的各向同性混合结构泡沫
Huan Jiang, Yanyu Chen
{"title":"Isotropic hybrid architected foams with enhanced energy absorption","authors":"Huan Jiang, Yanyu Chen","doi":"10.1117/12.2657645","DOIUrl":"https://doi.org/10.1117/12.2657645","url":null,"abstract":"Automotive and defense industries have been calling for the lightweight materials and structures with excellent energy absorption property under extreme operating conditions. Toward this end, random foams, and architected materials with different building blocks (beam, plate, and shell) have been investigated. However, most of the studied metamaterials exhibit anisotropic mechanical behavior upon different loading conditions. In practice, engineering materials are mostly expected to display isotropic mechanical properties at the macroscopic level. Random foams have been reported the first-generation man-made porous isotropic metamaterials, but they are characterized by the stochastic, uncontrollable topologies and material distributions which make them inferior candidates by contrast to architected metamaterials. In this work, we conducted systematically numerical experiment on a novel design of hybrid SC-BCC foam structure, which exhibits nearly isotropic mechanical behavior with nearly linear scaling relationship between relative stiffness and relative density. Remarkably, the proposed hybrid foam shows significantly improved stiffness, yield strength, and energy absorption compared to SC-foam. The stiffness and strength of hybrid foam are increased by 237% and 177% compared to SC-foam. The energy absorption of hybrid foam is increased by 96.5% and 28.1% compared to SC-foam and BCC-foam, respectively. The findings in our work offer new insights to design isotropic architected materials with enhanced mechanical performance that can find applications ranging from structural components of defense systems to protection systems in vehicles.","PeriodicalId":89272,"journal":{"name":"Smart structures and materials. Nondestructive evaluation for health monitoring and diagnostics","volume":"58 1","pages":"1248304 - 1248304-7"},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81404165","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
Making a brain on a structure: a conceptual study of elastic wave field neural networks for structural health monitoring 在结构上制造大脑:弹性波场神经网络用于结构健康监测的概念研究
A. Masuda, Ryu Sakai, Konosuke Takashima
{"title":"Making a brain on a structure: a conceptual study of elastic wave field neural networks for structural health monitoring","authors":"A. Masuda, Ryu Sakai, Konosuke Takashima","doi":"10.1117/12.2658694","DOIUrl":"https://doi.org/10.1117/12.2658694","url":null,"abstract":"The purpose of this study is to develop a novel concept of smart structural systems that can recognize their own structural integrity by an embodied high density sensor network. Over the past two decades, sensor networks for automatic inspection application have been intensively investigated, and it has now become reasonable to deploy over 1000 sensor nodes in a single structural system. It would be certain, however, that the current approaches that require rich electronics and wireless communication at each sensor node will reach its limit due to huge amount of data overwhelming the network capacity and centralized computing resources. In this study, we propose a new approach to make a breakthrough in both communication and computation for such high density sensor networks of the next generation. In our approach, a number of sensor nodes with simple functions are embedded in the structure, each of which reacts to the elastic waves propagating through the structure by applying a force to the structure after a simple nonlinear transformation. This allows the whole nodes to be mutually coupled through the medium of elastic waves, forming a neural network that incorporates the dynamic characteristics of the structure as the coupling weights. In this paper, we present a possible realization of our concept with basic formulations, and present numerical simulations to examine how the proposed network behaves under a single frequency input. It is presented that the network exhibits a bifurcation in its asymptotic behavior from modulated response to steady-state depending on the structural conditions.","PeriodicalId":89272,"journal":{"name":"Smart structures and materials. Nondestructive evaluation for health monitoring and diagnostics","volume":"15 1","pages":"124831J - 124831J-8"},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89423548","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
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