Volume 2: Mechanics and Behavior of Active Materials; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies最新文献

{"title":"Parametric Testing of Surrogate Knee Replacement Bearings With Embedded Piezoelectric Transducers","authors":"Justin L. Carlson, Zachariah Tiberi, M. Safaei, Robert I. Ponder, S. Anton","doi":"10.1115/SMASIS2018-8037","DOIUrl":"https://doi.org/10.1115/SMASIS2018-8037","url":null,"abstract":"In the United States, Total Knee Replacement (TKR) is a surgery many people go through, but frequently, patients find that they are unhappy post-surgery due to misalignment and loosening of the knee. An estimated 20% of knee replacement recipients report discomfort or undesired functionality within their first few years after surgery. Surgical techniques currently rely heavily on experience and tactile feedback to correctly align the knee replacement. If surgical teams were to have access to data regarding compartmental forces within the knee over the life of the implant, then a more precise balancing procedure could be implemented. As it stands, the only way to obtain this in vivo data is for patients to undergo post-operative fluoroscopy procedures; unfortunately, patients have no incentive to undergo this process. This study tests the capabilities of knee bearings embedded with piezoelectric transducers to estimate the magnitude and location of loading given certain inputs. The prototype is fabricated from ultra high molecular weight (UHMW) polyethylene using Computer Numerical Control (CNC) machining. For this study, to simulate loads under both normal and irregular knee positions, a custom fixture is designed and fabricated for use in a uniaxial load frame. The problem at hand necessitates a more realistic knee testing environment that can simulate the loading types of both balanced and imbalanced knees. Thus, the fixture permits various degrees of internal and external rotation. Additionally, through use of an X-Y translational table, the setup allows for in-plane translation between the condyles of the femoral component and the bearing prototype. This study compares values of force location from the piezoelectric sensors to measurements from pressure sensitive film. The piezoelectric knee bearing is tested to lay the groundwork for in vivo testing. Future work expanding upon this research would include designing and optimizing an in vivo knee bearing replacement to facilitate force location and magnitude data collection in a system free from external power sources by utilizing the energy harvesting capabilities of piezoelectrics.","PeriodicalId":117187,"journal":{"name":"Volume 2: Mechanics and Behavior of Active Materials; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128709524","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}

{"title":"Broadband Rotational Energy Harvesting Using Micro Energy Harvester","authors":"Jui-Ta Chien, Yung-Hsing Fu, Chao-Ting Chen, S. Lin, Y. Shu, Wen-Jong Wu","doi":"10.1115/SMASIS2018-8029","DOIUrl":"https://doi.org/10.1115/SMASIS2018-8029","url":null,"abstract":"This paper proposes a broadband rotational energy harvesting setup by using micro piezoelectric energy harvester (PEH). When driven in different rotating speed, the PEH can output relatively high power which exhibits the phenomenon of frequency up-conversion transforming the low frequency of rotation into the high frequency of resonant vibration. It aims to power self-powered devices used in the applications, like smart tires, smart bearings, and health monitoring sensors on rotational machines. Through the excitation of the rotary magnetic repulsion, the cantilever beam presents periodically damped oscillation. Under the rotational excitation, the maximum output voltage and power of PEH with optimal impedance is 28.2 Vpp and 663 μW, respectively. The output performance of the same energy harvester driven in ordinary vibrational based excitation is compared with rotational oscillation under open circuit condition. The maximum output voltage under 2.5g acceleration level of vibration is 27.54 Vpp while the peak output voltage of 36.5 Vpp in rotational excitation (in 265 rpm).","PeriodicalId":117187,"journal":{"name":"Volume 2: Mechanics and Behavior of Active Materials; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies","volume":"213 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122453177","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}

{"title":"Dangerous Scenes Recognition During Hoisting Based on Faster Region-Based Convolutional Neural Network","authors":"Hongguo Su, Mingyuan Zhang, Shengyuan Li, Xuefeng Zhao","doi":"10.1115/SMASIS2018-8226","DOIUrl":"https://doi.org/10.1115/SMASIS2018-8226","url":null,"abstract":"In the last couple of years, advancements in the deep learning, especially in convolutional neural networks, proved to be a boon for the image classification and recognition tasks. One of the important practical applications of object detection and image classification can be for security enhancement. If dangerous objects or scenes can be identified automatically, then a lot of accidents can be prevented. For this purpose, in this paper we made use of state-of-the-art implementation of Faster Region-based Convolutional Neural Network (Faster R-CNN) based on the monitoring video of hoisting sites to train a model to detect the dangerous object and the worker. By extracting the locations of them, object-human interactions during hoisting, mainly for changes in their spatial location relationship, can be understood whereby estimating whether the scene is safe or dangerous. Experimental results showed that the pre-trained model achieved good performance with a high mean average precision of 97.66% on object detection and the proposed method fulfilled the goal of dangerous scenes recognition perfectly.","PeriodicalId":117187,"journal":{"name":"Volume 2: Mechanics and Behavior of Active Materials; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122829751","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}

{"title":"On the Development of Tensorial Deformation-Resistivity Constitutive Relations in Conductive Nanofiller-Modified Composites","authors":"G. Koo, T. Tallman","doi":"10.1115/SMASIS2018-7965","DOIUrl":"https://doi.org/10.1115/SMASIS2018-7965","url":null,"abstract":"Polymers modified with conductive nanofillers have recently received considerable attention from the research community because of their deformation-dependent electrical resistivity. Known as piezoresistivity, this self-sensing capacity of nanocomposites has much potential for structural health monitoring (SHM). However, making effective use of the piezoresistive effect for SHM necessitates having a good understanding of the deformation-resistivity change relationship in these materials. While much insightful work has been done to model and predict the piezoresistive effect, many existing models suffer from important limitations such as being limited to microscales, over-predicting piezoresistive responses, and not considering complex deformations. We herein address these limitations by developing tensor-based piezoresistivity constitutive relations. The supposition of this approach is that resistivity changes due to small deformations can be treated as isotropic and be completely described by only two piezoresistive constants — one associated with volumetric strains and a second associated with shear strains. These piezoresistive constants can easily be discerned from simple experiments not unlike the process of determining elastic constants. We demonstrate the potential of this approach by deriving these piezoresistive constants for an experimentally-validated analytical model in the existing literature. This work can enable much more accurate and easily-obtained piezoresistive relations thereby greatly facilitating the potential of resistivity change-based SHM.","PeriodicalId":117187,"journal":{"name":"Volume 2: Mechanics and Behavior of Active Materials; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126474955","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}

{"title":"Diffusion-Resistant Coating for Harsh Environment Application of Piezoelectric Actuators","authors":"C. Behr, P. Wierach, M. Sinapius","doi":"10.1115/SMASIS2018-8234","DOIUrl":"https://doi.org/10.1115/SMASIS2018-8234","url":null,"abstract":"This paper presents the development process of an electrically insulating and liquid-impermeable coating for piezoelectric actuators. Against the background of flow investigations of an adaptive airfoil in a water tunnel the adaptive lip including PZT-ceramics for the active lip deformation must be insulated and sealed up against the ingress of moisture. Due to high electric field strength of 2 kV/mm between electrodes of multilayer actuators any ingress of moisture would lead to a reduction of the dielectric strength and may cause a short circuit. In order to prevent failure of the adaptive lip the electrical connections of the actuators have to be insulated by a waterproof coating. A service life of at least 107 load cycles at a frequency of 100 Hz is required for the actuators. Therefore the coating should be as ductile as possible otherwise it could crack and water could diffuse into the actuators. That is why the yield strength of the coating has to be higher than of the actuators, which is 0.3 %. For the investigation of the waterproofness several samples are coated with different materials in various processes. First the actuators are moulded in epoxy resin and then a diffusion-resistant PVF-foil is applied. After a screening of different materials, an additional coating with a two-component tar-epoxy resin in combination with a gold coating applied by a PVD process seems to be the most suitable process. Another promising waterproof coating is the atomic layer deposition (ALD). It is a slightly changed chemical vapor deposition (CVD) and referring to the studies of Abdulagatov et al. an ALD of aluminum oxide (Al2O3) and titanium dioxide (TiO2) can slow down the corrosion of static copper specimens in water for ∼80 days [1]. Through a redrying procedure during test intermissions an increased underwater service life of the piezoelectric actuators is achieved.","PeriodicalId":117187,"journal":{"name":"Volume 2: Mechanics and Behavior of Active Materials; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies","volume":"354 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132618094","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}

{"title":"Feature Recognition and Detection for Common Maintenance Tools Based on Deep Learning","authors":"Chengcheng Liu, Kuan Zhang, Peigang Li, Shengyuan Li, Xuefeng Zhao","doi":"10.1115/SMASIS2018-8266","DOIUrl":"https://doi.org/10.1115/SMASIS2018-8266","url":null,"abstract":"With the rapid development of rail traffic, the importance of railway overhaul is becoming increasingly prominent. Making an inventory on tools is an important step that railway workers must take before and after railway inspection. The tools left on the railway will cause great harm to train safety. To avoid this happening, the commonly used method is manual inventory at present, which is time-consuming, laborious and easily leads to omissions. In order to overcome these shortcomings, this paper proposes a Faster Region-based Convolutional Neural Network (Faster R-CNN)-based method for tools inventory. To realize the method, a Faster R-CNN architecture based on ZF-Net is modified and a database including a large number of images for 10 types of tools is built. Then the Faster R-CNN is trained and validated using the built database. The performance of the trained Faster R-CNN is evaluated using some new images which are not be used for training process. The result shows 95.0325% average precision (AP) ratings for 10 different types of tools and proves the proposed method is effective.","PeriodicalId":117187,"journal":{"name":"Volume 2: Mechanics and Behavior of Active Materials; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115629324","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}

{"title":"Distributed Strain Sensing Using Carbon Nanotube Thin Films and Electrical Time-Domain Reflectometry","authors":"B. Lee, K. Loh, F. L. Scalea","doi":"10.1115/SMASIS2018-7997","DOIUrl":"https://doi.org/10.1115/SMASIS2018-7997","url":null,"abstract":"Nondestructive inspection (NDI) is an effective technique to inspect, test, or evaluate the integrity of materials, components, and structures without interrupting the serviceability of a system. Despite recent advances in NDI techniques, most of them are either limited to sensing structural response at their instrumented locations or require multiple sensors and measurements to localize damage. In this study, a new NDI system that could achieve distributed sensing using a single measurement was investigated. Here, piezoresistive carbon nanotube (CNT)-polymer thin film sensors connected in a transmission line setup were interrogated using electrical time-domain reflectometry (ETDR). In ETDR, an electromagnetic signal is sent from one end of the transmission line. When the signal encounters the sensor, it can partially reflect and be captured at the same point. The characteristics of the reflected signal depend on the sensor’s impedance, which is correlated to structural response, deformation, or damage. The advantage of this is that distributed sensing along the entire transmission line can be achieved using a single measurement point. To validate this concept, CNT-polymer thin films that were integrated with a transmission line are subjected to uniaxial tensile strains applied using a load frame. The ETDR signals were analyzed to assess the system’s sensing performance.","PeriodicalId":117187,"journal":{"name":"Volume 2: Mechanics and Behavior of Active Materials; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115014031","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}

{"title":"Functionally Graded Cellular Contact-Aided Compliant Mechanism for Energy Absorption","authors":"J. Jovanova, Angela Nastevska, M. Frecker","doi":"10.1115/SMASIS2018-8175","DOIUrl":"https://doi.org/10.1115/SMASIS2018-8175","url":null,"abstract":"Cellular contact-aided compliant mechanisms (C3M) are cellular structures with integrated self-contact mechanisms, i.e. the segments can come into contact with each other during deformation. The contact changes the load path and can influence on the mechanism’s performance. Cellular contact-aided compliant mechanisms can be tailored for a specific structural application, such as energy absorption. Nickel Titanium compliant mechanisms can exploit the superelastic effect to improve performance and increase energy absorption. The potential for compliant mechanisms designed specifically for metal additive manufacturing opens the possibility of functional grading and tailoring the material properties locally for achieving overall performance. The combined effort of the geometry and the nonlinear material property increases the local compliance of the unit cell, resulting in higher energy absorption. A functionally graded 3D energy absorbing contact-aided compliant mechanisms cell with curved walls is analyzed. Functionally graded zones of higher flexibility are explored with different superelastic material properties. Introducing different moduli of elasticity as a function of the critical transformation stress results in different energy absorption. This approach can be used for tailoring the overall performance based on the application.","PeriodicalId":117187,"journal":{"name":"Volume 2: Mechanics and Behavior of Active Materials; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128094889","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}

{"title":"Passive Adaptive Wave Manipulation Using Nonlinear Acoustic Metamaterials","authors":"Sabiju Valiya Valappil, Catherine Sheehan, James M. Manimala","doi":"10.1115/SMASIS2018-7932","DOIUrl":"https://doi.org/10.1115/SMASIS2018-7932","url":null,"abstract":"Acoustic metamaterials display unusual mechanical wave manipulation behavior not seen in natural materials. In this study, nonlinear metamaterials with passive, amplitude-activated directional bandgaps are investigated. Test articles are constructed by installing periodic arrays of mass-loaded dome resonators on a square polycarbonate substrate. These resonators display nonlinear softening response with increase in excitation amplitude. Experiments conducted by mounting the test articles on low-stiffness boundaries along two adjacent sides and applying mechanical excitations at the opposite corner. A mechanically-staged laser vibrometer mounted overhead was used to make noncontact measurements at discrete plate and resonator locations. Measured displacement transmissibility verify the existence and extent of bandgap frequency ranges as well as amplitude-activated shifts in their bounds. Moreover, by tailoring the pattern of resonators within the array, preferential steering, focusing and selective beaming of waves within tunable frequency ranges depending on their amplitude are shown to be possible. Steady-state spatial maps depicting the displacement transmissibility field were generated from experiments and correlated with simulations to bring out underlying mechanisms. In addition, both lumped parameter and continuum models are considered to aid the design of scalable, passive adaptive metamaterial waveguides for applications ranging from seismic wave mitigation to MEMS transduction.","PeriodicalId":117187,"journal":{"name":"Volume 2: Mechanics and Behavior of Active Materials; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131269374","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}

{"title":"Modular Origami Robot Inspired by a Scorpion Tail","authors":"J. Jovanova, M. Anachkova, V. Gavriloski, Dimitar Petrevski, Franka Grazhdani, Damjan Pecioski","doi":"10.1115/SMASIS2018-8177","DOIUrl":"https://doi.org/10.1115/SMASIS2018-8177","url":null,"abstract":"Arthropod animals like scorpions with modular body parts can be an inspiration for a robot’s structure. The design presented here relays on inter-connected origami towers, but could also be easily disassembled. Each origami tower is fully autonomous and at the same time is part of the robot as a whole. The towers are positioned between two platforms that enable modularity. The scorpion’s tale shape is achieved by the varying platform diameter resulting in cone-like form. Each tower is actuated independently to enable multiple degrees of freedom. Maneuvering with separated units, assists in easier reparation as well as replacement. Detaching the towers into separate parts makes this structure develop more precise movements, since every unit will move autonomously. Therefore, having a higher number of separated movements combined leads to a smooth bionic movement. So, the overall hierarchy will be modular contributing to a greater curvature bending of the whole structure. Actuating and maneuvering the robot in the main concept is done by separated electro motors, built in the platform. The basic structure will be built from thick paper with plastic coatings. The thick paper itself is lightweight, but at the same time flexible. To protect the paper towers, double plastic foil is placed as an outer coating which acts as an origami cover. This transparent layer is elastic hence it can follow and support the individual units’ movements.\u0000 This work is focused on understanding origami towers kinematics and different combinations of inter-connected towers to achieve multiple degrees of freedom. A conceptual model is developed, supported by CAD and mathematical models. At the end a prototype is presented.","PeriodicalId":117187,"journal":{"name":"Volume 2: Mechanics and Behavior of Active Materials; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134227207","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}