Volume 1: Development and Characterization of Multifunctional Materials; Modeling, Simulation, and Control of Adaptive Systems; Integrated System Design and Implementation最新文献
J. Riemenschneider, M. Pohl, R. Unguran, V. Petrović, M. Kühn, A. Haldar, Hinesh Madhusoodanan, E. Jansen, R. Rolfes
In order to reduce the “cost of energy” for wind turbines it is an ongoing trend to increase the rotor diameter, which increases fatigue loads in the blade root area. Thus, a critical prerequisite for increased rotor diameter is the reduction of loads, which can be utilized by passive and active measures. This paper is giving an overview of current research work towards the use of a flexible trailing edge for load reduction as it is being pursued in the German national SmartBlades project. The active trailing edge is designed to change the lift of the outer blade in a way to counteract sudden changes caused by gusts or wind shear. Areas that are covered include the simulation towards the load reduction potential of such flexible trailing edges, the structural design of the trailing edge itself as a compliant mechanism, its experimental validation and fatigue investigation as well as multistable approaches for the design of such trailing edge flaps.
{"title":"Smart Trailing Edges for Wind Turbines","authors":"J. Riemenschneider, M. Pohl, R. Unguran, V. Petrović, M. Kühn, A. Haldar, Hinesh Madhusoodanan, E. Jansen, R. Rolfes","doi":"10.1115/SMASIS2018-7916","DOIUrl":"https://doi.org/10.1115/SMASIS2018-7916","url":null,"abstract":"In order to reduce the “cost of energy” for wind turbines it is an ongoing trend to increase the rotor diameter, which increases fatigue loads in the blade root area. Thus, a critical prerequisite for increased rotor diameter is the reduction of loads, which can be utilized by passive and active measures. This paper is giving an overview of current research work towards the use of a flexible trailing edge for load reduction as it is being pursued in the German national SmartBlades project. The active trailing edge is designed to change the lift of the outer blade in a way to counteract sudden changes caused by gusts or wind shear. Areas that are covered include the simulation towards the load reduction potential of such flexible trailing edges, the structural design of the trailing edge itself as a compliant mechanism, its experimental validation and fatigue investigation as well as multistable approaches for the design of such trailing edge flaps.","PeriodicalId":392289,"journal":{"name":"Volume 1: Development and Characterization of Multifunctional Materials; Modeling, Simulation, and Control of Adaptive Systems; Integrated System Design and Implementation","volume":"167 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":"131465625","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}
Pietro Bilancia, G. Berselli, U. Scarcia, G. Palli
Industrial robots are commonly designed to be very fast and stiff in order to achieve extremely precise position control capabilities. Nonetheless, high speeds and power do not allow for a safe physical interaction between robots and humans. With the exception of the latest generation lightweight arms, purposely design for human-robot collaborative tasks, safety devices shall be employed when workers enter the robots workspace, in order to reduce the chances of injuries. In this context, Variable Stiffness Actuators (VSA) potentially represent an effective solution for increasing robot safety. In light of this consideration, the present paper describes the design optimization of a VSA architecture previously proposed by the authors. In this novel embodiment, the VSA can achieve stiffness modulation via the use of a pair of compliant mechanisms with distributed compliance, which act as nonlinear springs with proper torque-deflection characteristic. Such elastic elements are composed of slender beams whose neutral axis is described by a spline curve with non-trivial shape. The beam geometry is determined by leveraging on a CAD/CAE framework allowing for the shape optimization of complex flexures. The design method makes use of the modeling and simulation capabilities of a parametric CAD software seamlessly connected to a FEM tool (i.e. Ansys Workbench). For validation purposes, proof-concept 3D printed prototypes of both non-linear elastic element and overall VSA are finally produced and tested. Experimental results fully confirm that the compliant mechanism behaves as expected.
{"title":"Design of a Beam-Based Variable Stiffness Actuator via Shape Optimization in a CAD/CAE Environment","authors":"Pietro Bilancia, G. Berselli, U. Scarcia, G. Palli","doi":"10.1115/SMASIS2018-8053","DOIUrl":"https://doi.org/10.1115/SMASIS2018-8053","url":null,"abstract":"Industrial robots are commonly designed to be very fast and stiff in order to achieve extremely precise position control capabilities. Nonetheless, high speeds and power do not allow for a safe physical interaction between robots and humans. With the exception of the latest generation lightweight arms, purposely design for human-robot collaborative tasks, safety devices shall be employed when workers enter the robots workspace, in order to reduce the chances of injuries. In this context, Variable Stiffness Actuators (VSA) potentially represent an effective solution for increasing robot safety. In light of this consideration, the present paper describes the design optimization of a VSA architecture previously proposed by the authors. In this novel embodiment, the VSA can achieve stiffness modulation via the use of a pair of compliant mechanisms with distributed compliance, which act as nonlinear springs with proper torque-deflection characteristic. Such elastic elements are composed of slender beams whose neutral axis is described by a spline curve with non-trivial shape. The beam geometry is determined by leveraging on a CAD/CAE framework allowing for the shape optimization of complex flexures. The design method makes use of the modeling and simulation capabilities of a parametric CAD software seamlessly connected to a FEM tool (i.e. Ansys Workbench). For validation purposes, proof-concept 3D printed prototypes of both non-linear elastic element and overall VSA are finally produced and tested. Experimental results fully confirm that the compliant mechanism behaves as expected.","PeriodicalId":392289,"journal":{"name":"Volume 1: Development and Characterization of Multifunctional Materials; Modeling, Simulation, and Control of Adaptive Systems; Integrated System Design and Implementation","volume":"225 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132228392","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}
Dielectric elastomers are employed on a wide variety of adaptive structures. Many of these soft elastomers exhibit significant rate-dependencies in their response. Accurately quantifying this viscoelastic behavior is non-trivial and in many instances a nonlinear modeling framework is required. Fractional-order operators have been applied to modeling viscoelastic behavior for many years, and recent research has shown fractional-order methods to be effective for nonlinear frameworks. This implementation can become computationally expensive to achieve an accurate approximation of the fractional-order derivative. In this paper, we demonstrate the effectiveness of using quadrature techniques in approximating the Riemann-Liouville definition for fractional derivatives in the context of developing a nonlinear viscoelastic model.
{"title":"Numerical Techniques to Model Fractional-Order Nonlinear Viscoelasticity in Soft Elastomers","authors":"P. Miles, G. Pash, W. Oates, Ralph C. Smith","doi":"10.1115/SMASIS2018-8102","DOIUrl":"https://doi.org/10.1115/SMASIS2018-8102","url":null,"abstract":"Dielectric elastomers are employed on a wide variety of adaptive structures. Many of these soft elastomers exhibit significant rate-dependencies in their response. Accurately quantifying this viscoelastic behavior is non-trivial and in many instances a nonlinear modeling framework is required. Fractional-order operators have been applied to modeling viscoelastic behavior for many years, and recent research has shown fractional-order methods to be effective for nonlinear frameworks. This implementation can become computationally expensive to achieve an accurate approximation of the fractional-order derivative. In this paper, we demonstrate the effectiveness of using quadrature techniques in approximating the Riemann-Liouville definition for fractional derivatives in the context of developing a nonlinear viscoelastic model.","PeriodicalId":392289,"journal":{"name":"Volume 1: Development and Characterization of Multifunctional Materials; Modeling, Simulation, and Control of Adaptive Systems; Integrated System Design and Implementation","volume":"5 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":"134293486","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}
B. Kiefer, J. Hein, M. Abendroth, H. Biermann, S. Henkel, T. Niendorf, P. Krooß, Y. Chemisky
This work presents a first investigation of the small punch test (SPT) as a possible method to identify material parameters for shape memory alloy (SMA) behavior. In comparison to more common tests, the SPT has advantages in setup simplicity, small sample size, uncomplicated shape, and the possibility of specimen clamping, while offering controlled multi axial loading. Different loading scenarios are described and executed. The parameters of an established SMA model are subsequently (partially) calibrated from the measured SPT force-deflection curves. For some loading regimes, the effective response curves suggest the occurrence of damage events. To investigate the underlying microscale failure mechanisms, a first SEM study was conducted. These first results underline that the SPT is a promising efficient and inexpensive characterization method to support SMA constitutive model development under multiaxial loading — including aspects of damage, fracture and fatigue.
{"title":"On the Potential of Using the Small Punch Test for the Characterization of SMA Behavior Under Multi-Axial Loading Conditions","authors":"B. Kiefer, J. Hein, M. Abendroth, H. Biermann, S. Henkel, T. Niendorf, P. Krooß, Y. Chemisky","doi":"10.1115/SMASIS2018-7973","DOIUrl":"https://doi.org/10.1115/SMASIS2018-7973","url":null,"abstract":"This work presents a first investigation of the small punch test (SPT) as a possible method to identify material parameters for shape memory alloy (SMA) behavior. In comparison to more common tests, the SPT has advantages in setup simplicity, small sample size, uncomplicated shape, and the possibility of specimen clamping, while offering controlled multi axial loading. Different loading scenarios are described and executed. The parameters of an established SMA model are subsequently (partially) calibrated from the measured SPT force-deflection curves. For some loading regimes, the effective response curves suggest the occurrence of damage events. To investigate the underlying microscale failure mechanisms, a first SEM study was conducted. These first results underline that the SPT is a promising efficient and inexpensive characterization method to support SMA constitutive model development under multiaxial loading — including aspects of damage, fracture and fatigue.","PeriodicalId":392289,"journal":{"name":"Volume 1: Development and Characterization of Multifunctional Materials; Modeling, Simulation, and Control of Adaptive Systems; Integrated System Design and Implementation","volume":"62 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":"114083929","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}
Serket Quintanar-Guzman, S. Kannan, H. Voos, M. Darouach, M. Alma
This article presents the experimental validation of a Direct Adaptive Control for angular position regulation of a lightweight robotic arm. The robotic arm is single degree-of-freedom (DOF) system, actuated by two Shape Memory Alloy (SMA) wires. The proposed adaptive control is capable of adapting itself to the hysteretic behavior of SMA wires and update its behavior to deal with the changing parameters of the material over time. The closed-loop approach is tested experimentally showing its effectiveness to deal with the highly nonlinear dynamics of the SMA wires. These results are discussed and compared with a classical control approach. The updated design and hardware development and modeling of the robotic arm are shown.
{"title":"Experimental Validation of Adaptive Control for a Shape Memory Alloy Actuated Lightweight Robotic Arm","authors":"Serket Quintanar-Guzman, S. Kannan, H. Voos, M. Darouach, M. Alma","doi":"10.1115/SMASIS2018-8165","DOIUrl":"https://doi.org/10.1115/SMASIS2018-8165","url":null,"abstract":"This article presents the experimental validation of a Direct Adaptive Control for angular position regulation of a lightweight robotic arm. The robotic arm is single degree-of-freedom (DOF) system, actuated by two Shape Memory Alloy (SMA) wires. The proposed adaptive control is capable of adapting itself to the hysteretic behavior of SMA wires and update its behavior to deal with the changing parameters of the material over time. The closed-loop approach is tested experimentally showing its effectiveness to deal with the highly nonlinear dynamics of the SMA wires. These results are discussed and compared with a classical control approach. The updated design and hardware development and modeling of the robotic arm are shown.","PeriodicalId":392289,"journal":{"name":"Volume 1: Development and Characterization of Multifunctional Materials; Modeling, Simulation, and Control of Adaptive Systems; Integrated System Design and Implementation","volume":"16 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":"114443079","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}
This paper examines the feasibility of piezocomposite morphing airfoils and trailing edge control surfaces subjected to large dynamic pressures. Piezocomposite airfoils have been shown to be feasible on small unmanned aerial vehicles, subject to relatively low dynamic pressures, operating in the Reynold’s number range of 50k to 250k. The operating range of interest in this paper has a cruising Reynold’s number range between 250k and 1M subject to relatively large wing loading. This range of Reynold’s numbers has not been explored in detail due to the large aerodynamic loads produced. Based on the authors’ previous research on small unmanned aircraft, the proposed concept is a variable-camber airfoil that employs a continuous inextensible surface and surface-bonded piezocomposite actuators. To achieve camber-morphing, multiple piezocomposite actuating elements are applied to the upper and lower surfaces. A case study is performed to determine the design parameters of the airfoil. The parameters to be varied include the substrate thickness of the baseline airfoil, leading edge, and piezocomposite bonded areas. In addition, the positions of the piezocomposites are varied. The analysis is performed using a coupled fluid-structure interaction model assuming static aeroelastic behavior. A voltage sweep is conducted on each airfoil design while being subjected to 70 m/s free stream velocity. The sweep examines the lift coefficient and lift-to-drag ratio of the airfoil over the full operational range. This research lays the groundwork for determining the feasibility of piezocomposite morphing airfoil and trailing edge concepts for use in applications subject to large dynamic pressures.
{"title":"A Piezocomposite Trailing-Edge for Subsonic Aircraft","authors":"C. Wright, O. Bilgen","doi":"10.1115/SMASIS2018-7943","DOIUrl":"https://doi.org/10.1115/SMASIS2018-7943","url":null,"abstract":"This paper examines the feasibility of piezocomposite morphing airfoils and trailing edge control surfaces subjected to large dynamic pressures. Piezocomposite airfoils have been shown to be feasible on small unmanned aerial vehicles, subject to relatively low dynamic pressures, operating in the Reynold’s number range of 50k to 250k. The operating range of interest in this paper has a cruising Reynold’s number range between 250k and 1M subject to relatively large wing loading. This range of Reynold’s numbers has not been explored in detail due to the large aerodynamic loads produced. Based on the authors’ previous research on small unmanned aircraft, the proposed concept is a variable-camber airfoil that employs a continuous inextensible surface and surface-bonded piezocomposite actuators. To achieve camber-morphing, multiple piezocomposite actuating elements are applied to the upper and lower surfaces. A case study is performed to determine the design parameters of the airfoil. The parameters to be varied include the substrate thickness of the baseline airfoil, leading edge, and piezocomposite bonded areas. In addition, the positions of the piezocomposites are varied. The analysis is performed using a coupled fluid-structure interaction model assuming static aeroelastic behavior. A voltage sweep is conducted on each airfoil design while being subjected to 70 m/s free stream velocity. The sweep examines the lift coefficient and lift-to-drag ratio of the airfoil over the full operational range. This research lays the groundwork for determining the feasibility of piezocomposite morphing airfoil and trailing edge concepts for use in applications subject to large dynamic pressures.","PeriodicalId":392289,"journal":{"name":"Volume 1: Development and Characterization of Multifunctional Materials; Modeling, Simulation, and Control of Adaptive Systems; Integrated System Design and Implementation","volume":"23 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":"114618928","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}
This paper aims at highlighting the fabrication procedures and proof-of-concept tests of a Kirigami inspired multi-stable composite laminate. Bistable composites consisting of asymmetric fiber layout have shown great potentials for shape morphing and energy harvesting applications. However, a patch of such a bistable composite is limited to very simple deformation when being snapped between its two stable equilibria (or states). To address this issue, this study investigates the idea of utilizing Kirigami, the ancient art of paper cutting, into the design and fabrication of bistable composite laminates. Via combining multiple patches of laminates and cutting according to prescribed Kirigami pattern, one can create a structure with multiple stable states and sophisticated deformation paths between them. This can significantly expand the application potentials of the multi-stable composites. This paper details the fabrication procedures for an elementary unit cell in the envisioned Kirigami composite and the results of proof-of-concept experiments, which measure the force required to switch the Kirigami composite between its different stable states. Preliminary results confirm that the Kirigami unit cell possesses multiple stable states depending on the underlying fiber layout. Each patch in the Kirigami composite could be snapped independently between stable states without triggering any undesired snapping in other patches. Moreover, a transient propagation of curvature change is observed when a patch in the Kirigami composite is snapped between its stable states. Such a phenomenon has not been reported in the bistable composite studies before. Results of this paper indicate that Kirigami is a powerful approach for designing and fabricating multi-stable composites with a strong appeal for morphing and adaptive systems. This paper highlights the feasibility and novelty of combining Kirigami art and bistable adaptive composites.
{"title":"Fabrication and Testing of Kirigami-Inspired Multi-Stable Composites","authors":"Aditya Lele, O. Myers, Suyi Li","doi":"10.1115/SMASIS2018-7981","DOIUrl":"https://doi.org/10.1115/SMASIS2018-7981","url":null,"abstract":"This paper aims at highlighting the fabrication procedures and proof-of-concept tests of a Kirigami inspired multi-stable composite laminate. Bistable composites consisting of asymmetric fiber layout have shown great potentials for shape morphing and energy harvesting applications. However, a patch of such a bistable composite is limited to very simple deformation when being snapped between its two stable equilibria (or states). To address this issue, this study investigates the idea of utilizing Kirigami, the ancient art of paper cutting, into the design and fabrication of bistable composite laminates. Via combining multiple patches of laminates and cutting according to prescribed Kirigami pattern, one can create a structure with multiple stable states and sophisticated deformation paths between them. This can significantly expand the application potentials of the multi-stable composites. This paper details the fabrication procedures for an elementary unit cell in the envisioned Kirigami composite and the results of proof-of-concept experiments, which measure the force required to switch the Kirigami composite between its different stable states. Preliminary results confirm that the Kirigami unit cell possesses multiple stable states depending on the underlying fiber layout. Each patch in the Kirigami composite could be snapped independently between stable states without triggering any undesired snapping in other patches. Moreover, a transient propagation of curvature change is observed when a patch in the Kirigami composite is snapped between its stable states. Such a phenomenon has not been reported in the bistable composite studies before. Results of this paper indicate that Kirigami is a powerful approach for designing and fabricating multi-stable composites with a strong appeal for morphing and adaptive systems. This paper highlights the feasibility and novelty of combining Kirigami art and bistable adaptive composites.","PeriodicalId":392289,"journal":{"name":"Volume 1: Development and Characterization of Multifunctional Materials; Modeling, Simulation, and Control of Adaptive Systems; Integrated System Design and Implementation","volume":"152 1 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":"123570097","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}
V. V. S. Malladi, M. Albakri, P. Tarazaga, S. Gugercin
Dispersion relations describe the frequency-dependent nature of elastic waves propagating in structures. Experimental determination of dispersion relations of structural components, such as the floor of a building, can be a tedious task, due to material inhomogeneity, complex boundary conditions, and the physical dimensions of the structure under test. In this work, data-driven modeling techniques are utilized to reconstruct dispersion relations over a predetermined frequency range. The feasibility of this approach is demonstrated on a one-dimensional beam where an exact solution of the dispersion relations is attainable. Frequency response functions of the beam are obtained numerically over the frequency range of 0–50kHz. Data-driven dynamical model, constructed by the vector fitting approach, is then deployed to develop a state-space model based on the simulated frequency response functions at 16 locations along the beam. This model is then utilized to construct dispersion relations of the structure through a series of numerical simulations. The techniques discussed in this paper are especially beneficial to such scenarios where it is neither possible to find analytical solutions to wave equations, nor it is feasible to measure dispersion curves experimentally. In the present work, actual experimental data is left for future work, but the complete framework is presented here.
{"title":"Data-Driven Modeling Techniques to Estimate Dispersion Relations of Structural Components","authors":"V. V. S. Malladi, M. Albakri, P. Tarazaga, S. Gugercin","doi":"10.1115/SMASIS2018-8135","DOIUrl":"https://doi.org/10.1115/SMASIS2018-8135","url":null,"abstract":"Dispersion relations describe the frequency-dependent nature of elastic waves propagating in structures. Experimental determination of dispersion relations of structural components, such as the floor of a building, can be a tedious task, due to material inhomogeneity, complex boundary conditions, and the physical dimensions of the structure under test.\u0000 In this work, data-driven modeling techniques are utilized to reconstruct dispersion relations over a predetermined frequency range. The feasibility of this approach is demonstrated on a one-dimensional beam where an exact solution of the dispersion relations is attainable. Frequency response functions of the beam are obtained numerically over the frequency range of 0–50kHz. Data-driven dynamical model, constructed by the vector fitting approach, is then deployed to develop a state-space model based on the simulated frequency response functions at 16 locations along the beam. This model is then utilized to construct dispersion relations of the structure through a series of numerical simulations. The techniques discussed in this paper are especially beneficial to such scenarios where it is neither possible to find analytical solutions to wave equations, nor it is feasible to measure dispersion curves experimentally. In the present work, actual experimental data is left for future work, but the complete framework is presented here.","PeriodicalId":392289,"journal":{"name":"Volume 1: Development and Characterization of Multifunctional Materials; Modeling, Simulation, and Control of Adaptive Systems; Integrated System Design and Implementation","volume":"20 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":"123867791","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}
A. Gaspari, A. Gilardelli, S. Ricci, A. Airoldi, F. Moens
This paper summarizes the results obtained in the framework of Clean Sky 2 REG-IADP, AIRGREEN on the development of a dedicated morphing device, i.e. a Leading Edge morphing. This device, designed so to be installed on a advanced, twin prop, regional aircraft, is conceived to guarantee high lift conditions together with a smoothed and continuous skin surface, especially important due to the presence of a laminar wing. The design of a such as complex devices required a multi-disciplinary approach, able to combine the aerodynamic performances and the structural ones related to the compliant structures concept adopted for the internal structure. The paper includes an overview of all the design challenges, the adopted solutions and finally the obtained numerical assessments.
{"title":"Design of a Leading Edge Morphing Based on Compliant Structures in the Framework of the CS2-AIRGREEN2 Project","authors":"A. Gaspari, A. Gilardelli, S. Ricci, A. Airoldi, F. Moens","doi":"10.1115/SMASIS2018-8246","DOIUrl":"https://doi.org/10.1115/SMASIS2018-8246","url":null,"abstract":"This paper summarizes the results obtained in the framework of Clean Sky 2 REG-IADP, AIRGREEN on the development of a dedicated morphing device, i.e. a Leading Edge morphing. This device, designed so to be installed on a advanced, twin prop, regional aircraft, is conceived to guarantee high lift conditions together with a smoothed and continuous skin surface, especially important due to the presence of a laminar wing. The design of a such as complex devices required a multi-disciplinary approach, able to combine the aerodynamic performances and the structural ones related to the compliant structures concept adopted for the internal structure. The paper includes an overview of all the design challenges, the adopted solutions and finally the obtained numerical assessments.","PeriodicalId":392289,"journal":{"name":"Volume 1: Development and Characterization of Multifunctional Materials; Modeling, Simulation, and Control of Adaptive Systems; Integrated System Design and Implementation","volume":"115 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":"123953513","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}
Liquid crystalline (LC) behaviors of cellulose nanocrystal (CNC), derived from wood, cotton or other cellulose-based biopolymers, have been actively investigated due to their unique optical properties and their superb mechanical properties, which open up potential applications in bioelectronics and biomedical engineering. In particular, many attempts have been made to control phase and orientation of LC-CNCs because they are critical factors deciding optical and mechanical properties, and electromechanical performances. Through the applications of mechanical force, electric field and magnetic field, some degree of success has been achieved; however, realizing homogeneous arrangements of CNCs that can be exploited at the macroscale is still elusive, owing to a variety of intermolecular interactions. The characterizations of the LC phase and orientation of CNCs are also challenging due to their complex biological structures. In this report, we introduce approaches to control the phase and orientation of LC-CNCs through the self-assembly, mechanical force and electric field. The liquid crystalline behaviors of CNCs in polar solvents and at the air/water interface are discussed. Translational and rotational behaviors of CNCs under DC electric field are also investigated as a function of their surface charge and dipole moment. In addition, we introduce a nonlinear optical process, namely, sum frequency generation (SFG) spectroscopy, for the structural characterization of LC-CNCs. Using SFG, we can analyze not only crystal phase and structure, but also polar ordering of CNCs which plays a key role in determining their electromechanical performances. Development of cellulose-based smart materials will expand the spectrum of available functional materials that are lightweight, flexible, mechanically tough, and thermally stable at moderately high temperatures (up to 300°C).
{"title":"Tailoring and Characterization of the Liquid Crystalline Structure of Cellulose Nanocrystals for Opto-Electro-Mechanical Multifunctional Applications","authors":"Inseok Chae, A. Meddeb, Z. Ounaies, Seong H. Kim","doi":"10.1115/SMASIS2018-8016","DOIUrl":"https://doi.org/10.1115/SMASIS2018-8016","url":null,"abstract":"Liquid crystalline (LC) behaviors of cellulose nanocrystal (CNC), derived from wood, cotton or other cellulose-based biopolymers, have been actively investigated due to their unique optical properties and their superb mechanical properties, which open up potential applications in bioelectronics and biomedical engineering. In particular, many attempts have been made to control phase and orientation of LC-CNCs because they are critical factors deciding optical and mechanical properties, and electromechanical performances. Through the applications of mechanical force, electric field and magnetic field, some degree of success has been achieved; however, realizing homogeneous arrangements of CNCs that can be exploited at the macroscale is still elusive, owing to a variety of intermolecular interactions. The characterizations of the LC phase and orientation of CNCs are also challenging due to their complex biological structures. In this report, we introduce approaches to control the phase and orientation of LC-CNCs through the self-assembly, mechanical force and electric field. The liquid crystalline behaviors of CNCs in polar solvents and at the air/water interface are discussed. Translational and rotational behaviors of CNCs under DC electric field are also investigated as a function of their surface charge and dipole moment. In addition, we introduce a nonlinear optical process, namely, sum frequency generation (SFG) spectroscopy, for the structural characterization of LC-CNCs. Using SFG, we can analyze not only crystal phase and structure, but also polar ordering of CNCs which plays a key role in determining their electromechanical performances. Development of cellulose-based smart materials will expand the spectrum of available functional materials that are lightweight, flexible, mechanically tough, and thermally stable at moderately high temperatures (up to 300°C).","PeriodicalId":392289,"journal":{"name":"Volume 1: Development and Characterization of Multifunctional Materials; Modeling, Simulation, and Control of Adaptive Systems; Integrated System Design and Implementation","volume":"4 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":"124992556","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}
Volume 1: Development and Characterization of Multifunctional Materials; Modeling, Simulation, and Control of Adaptive Systems; Integrated System Design and Implementation