Qianwei Zhang, R. Fotouhi, Joshua Cote, Majid Khak Pour
Crop monitoring is frequently used by crop scientists to observe growth of plants and to relate plants phenotypes to their genotypes. Instead of traditional crop monitoring, which is labor intensive, high-throughput plant phenotyping (HTP) platforms using ground-based vehicle have several advantages over manual methods. Existing HTP platforms with robot arms has limited reach and payload, and they are sometimes not appropriate for monitoring large fields. In this research, a 5-DOF robot arm is developed and analyzed for monitoring several crops growth. This robot arm is a hybrid of both prismatic and rotational joints. This new mobile manipulator is light, has a compact structure, suitable for plant phenotyping, and doesn’t exist commercially. To investigate the performance of the robot arm, kinematics and dynamics analyses using Newton-Euler iterative method and MATLAB simulations are performed. Results matched with each other very well.
{"title":"Lightweight Long-Reach 5-DOF Robot Arm for Farm Application","authors":"Qianwei Zhang, R. Fotouhi, Joshua Cote, Majid Khak Pour","doi":"10.1115/detc2019-98366","DOIUrl":"https://doi.org/10.1115/detc2019-98366","url":null,"abstract":"\u0000 Crop monitoring is frequently used by crop scientists to observe growth of plants and to relate plants phenotypes to their genotypes. Instead of traditional crop monitoring, which is labor intensive, high-throughput plant phenotyping (HTP) platforms using ground-based vehicle have several advantages over manual methods. Existing HTP platforms with robot arms has limited reach and payload, and they are sometimes not appropriate for monitoring large fields. In this research, a 5-DOF robot arm is developed and analyzed for monitoring several crops growth. This robot arm is a hybrid of both prismatic and rotational joints. This new mobile manipulator is light, has a compact structure, suitable for plant phenotyping, and doesn’t exist commercially. To investigate the performance of the robot arm, kinematics and dynamics analyses using Newton-Euler iterative method and MATLAB simulations are performed. Results matched with each other very well.","PeriodicalId":211780,"journal":{"name":"Volume 5B: 43rd Mechanisms and Robotics Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134166118","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 novel 5-DOF 3T2R parallel manipulator is designed with chains in perpendicular planes. The synthesis is based on motion sets intersection and disseminated Chebychev-Grübler-Kutzbach formula. A boundary offset method is developed to detect link interference. Multi-objective optimization is practiced on the design for improved performances. Stiffness based on oriented platform coordinate is developed. This paper also discusses the potential applications of the design.
{"title":"Novel Design of a 3T2R 5-DOF Parallel Manipulator","authors":"Zhongxing Yang, Dan Zhang","doi":"10.1115/detc2019-97088","DOIUrl":"https://doi.org/10.1115/detc2019-97088","url":null,"abstract":"\u0000 A novel 5-DOF 3T2R parallel manipulator is designed with chains in perpendicular planes. The synthesis is based on motion sets intersection and disseminated Chebychev-Grübler-Kutzbach formula. A boundary offset method is developed to detect link interference. Multi-objective optimization is practiced on the design for improved performances. Stiffness based on oriented platform coordinate is developed. This paper also discusses the potential applications of the design.","PeriodicalId":211780,"journal":{"name":"Volume 5B: 43rd Mechanisms and Robotics Conference","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131772874","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}
Small-scale origami inspired assemblages are usually made with soft compliant plates to serve as creases because it is difficult to fabricate real hinges at those scales. In most conventional origami modeling techniques, these soft and compliant creases are usually neglected and simplified as concentrated rotational springs. Such simplification does not capture the three dimensional geometry correctly and also neglects torsional and extensional deformations of the compliant creases. These deformations could be significant for determining advanced mechanical behaviors of the origami such as bistablity and multistablity. In this paper an improved formulation of a simple bar and hinge model is proposed to capture the geometry and flexibility of compliant creases. Equations for assigning bar areas and spring stiffness are derived based on the theoretical plane stress plate models and the pseudo-rigid model. These equations are next verified against finite element simulations for both infinitesimal stiffness and large deformation stiffness. It is found that the proposed model can predict stiffness characteristics of compliant crease origami relatively well. Furthermore, two examples are used to demonstrate the efficiency and capability of the proposed model.
{"title":"Simulating Compliant Crease Origami With a Bar and Hinge Model","authors":"Yi Zhu, E. Filipov","doi":"10.1115/detc2019-97119","DOIUrl":"https://doi.org/10.1115/detc2019-97119","url":null,"abstract":"\u0000 Small-scale origami inspired assemblages are usually made with soft compliant plates to serve as creases because it is difficult to fabricate real hinges at those scales. In most conventional origami modeling techniques, these soft and compliant creases are usually neglected and simplified as concentrated rotational springs. Such simplification does not capture the three dimensional geometry correctly and also neglects torsional and extensional deformations of the compliant creases. These deformations could be significant for determining advanced mechanical behaviors of the origami such as bistablity and multistablity. In this paper an improved formulation of a simple bar and hinge model is proposed to capture the geometry and flexibility of compliant creases. Equations for assigning bar areas and spring stiffness are derived based on the theoretical plane stress plate models and the pseudo-rigid model. These equations are next verified against finite element simulations for both infinitesimal stiffness and large deformation stiffness. It is found that the proposed model can predict stiffness characteristics of compliant crease origami relatively well. Furthermore, two examples are used to demonstrate the efficiency and capability of the proposed model.","PeriodicalId":211780,"journal":{"name":"Volume 5B: 43rd Mechanisms and Robotics Conference","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125379064","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}
Shape-Morphing Mechanism Arrays (SMMAs) can be made by arraying harmonic four-bar mechanisms, i.e. four-bar mechanisms with a particular structure that insures high levels of symmetry. This paper discusses a particular genre of harmonic mechanism array that can forms rectangular grids without requiring the exclusive use of parallel mechanisms. Such arrays can be designed to preserve their harmonic (highly symmetric) structure through-out their range of motion, producing arrays capable of large deformations that nevertheless can be characterized by a 2D tensor, specifically, rectangular arrays deform as parallelograms.
{"title":"Design and Tensorial Characterization of Rectangular Harmonic Shape-Morphing Mechanism Arrays","authors":"C. Lusk","doi":"10.1115/detc2019-98292","DOIUrl":"https://doi.org/10.1115/detc2019-98292","url":null,"abstract":"\u0000 Shape-Morphing Mechanism Arrays (SMMAs) can be made by arraying harmonic four-bar mechanisms, i.e. four-bar mechanisms with a particular structure that insures high levels of symmetry. This paper discusses a particular genre of harmonic mechanism array that can forms rectangular grids without requiring the exclusive use of parallel mechanisms. Such arrays can be designed to preserve their harmonic (highly symmetric) structure through-out their range of motion, producing arrays capable of large deformations that nevertheless can be characterized by a 2D tensor, specifically, rectangular arrays deform as parallelograms.","PeriodicalId":211780,"journal":{"name":"Volume 5B: 43rd Mechanisms and Robotics Conference","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124518849","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}
Quality control in the pharmaceutical industries is a critical issue. It consists of a sampling phase and an analysis phase. There are different ways of taking a sample to be submitted for a quality control: from static to dynamic methods, from simple to more complex solutions. All these traditional procedures and their results are strictly dependent on the operator, due to the fact that this type of environment is unstructured and not very often robotised. For this reason, the aim of the paper is to push forward the state of art in the sampling methods for quality controls, by presenting a totally robotic solution in the framework of dust samples collection from closed containers.
{"title":"Design of a Totally Robotic Solution for Sampling in Pharmaceutical Industry","authors":"Mariapaola D’Imperio, F. Cannella","doi":"10.1115/detc2019-97734","DOIUrl":"https://doi.org/10.1115/detc2019-97734","url":null,"abstract":"\u0000 Quality control in the pharmaceutical industries is a critical issue. It consists of a sampling phase and an analysis phase. There are different ways of taking a sample to be submitted for a quality control: from static to dynamic methods, from simple to more complex solutions. All these traditional procedures and their results are strictly dependent on the operator, due to the fact that this type of environment is unstructured and not very often robotised. For this reason, the aim of the paper is to push forward the state of art in the sampling methods for quality controls, by presenting a totally robotic solution in the framework of dust samples collection from closed containers.","PeriodicalId":211780,"journal":{"name":"Volume 5B: 43rd Mechanisms and Robotics Conference","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132550634","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}
Bai Lele, Lubin Hang, Xiaobo Huang, Mingyuan Wang, Liu Ziyu
Space deployable structures that are constructed by the single loop over-constrained linkages have been extensively applied in the fields of aerospace and construction. The pressure angle regarded as an important index to measure the performance of the basic units has attracted more and more attention. The kinematic model of the Bennett linkage is studied by the D-H matrix and the analytic formula of the pressure angle has been deducted through kinematic equations. The rule of the Bennett linkage has been discovered that the minimum pressure angle occurs while the input angle equals nπ + π / 2(n ∈ N). According to the linkage configuration at the input angle of π / 2, the geometric meaning is revealed that the minimum pressure angle of the linkage is the same as the twist angle of the joint axes of the output link. Finally, conclusions can also be drawn that the smaller the twist angle of the output link is, the smaller the minimum pressure angle will be. The research enriches the kinematics of Bennett linkage and provides a reference for its engineering applications.
{"title":"Research on Minimum Pressure Angle of Bennett Linkage","authors":"Bai Lele, Lubin Hang, Xiaobo Huang, Mingyuan Wang, Liu Ziyu","doi":"10.1115/detc2019-98232","DOIUrl":"https://doi.org/10.1115/detc2019-98232","url":null,"abstract":"\u0000 Space deployable structures that are constructed by the single loop over-constrained linkages have been extensively applied in the fields of aerospace and construction. The pressure angle regarded as an important index to measure the performance of the basic units has attracted more and more attention. The kinematic model of the Bennett linkage is studied by the D-H matrix and the analytic formula of the pressure angle has been deducted through kinematic equations. The rule of the Bennett linkage has been discovered that the minimum pressure angle occurs while the input angle equals nπ + π / 2(n ∈ N). According to the linkage configuration at the input angle of π / 2, the geometric meaning is revealed that the minimum pressure angle of the linkage is the same as the twist angle of the joint axes of the output link. Finally, conclusions can also be drawn that the smaller the twist angle of the output link is, the smaller the minimum pressure angle will be. The research enriches the kinematics of Bennett linkage and provides a reference for its engineering applications.","PeriodicalId":211780,"journal":{"name":"Volume 5B: 43rd Mechanisms and Robotics Conference","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134569928","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 investigates the potential of kirigami-folding with the addition of strategically placed cuts at multiple scales through both computational design and physical prototyping. The study develops a novel method and workflow for generating two-dimensional (2D) kirigami patterns developed from doubly curved three-dimensional (3D) surfaces (Inverse process). Corresponding simulations of the kirigami folding motion from 2D pattern to 3D goal shape are presented (Forward process). The workflow is based on a reciprocal feedback loop including computational design, finite element analysis, dynamic simulation and physical prototyping. Extended from previous research on kirigami geometry, this paper incorporates material properties into the folding process and successfully develops active kirigami models from the DNA scale to human scale. The results presented in this paper provide an attractive method for kirigami design and fabrication with a wide range of scales and applications.
{"title":"Programmable Kirigami: Cutting and Folding in Science, Technology and Architecture","authors":"Jingyang Liu, Grace Chuang, H. C. Sang, J. Sabin","doi":"10.1115/detc2019-97557","DOIUrl":"https://doi.org/10.1115/detc2019-97557","url":null,"abstract":"\u0000 This paper investigates the potential of kirigami-folding with the addition of strategically placed cuts at multiple scales through both computational design and physical prototyping. The study develops a novel method and workflow for generating two-dimensional (2D) kirigami patterns developed from doubly curved three-dimensional (3D) surfaces (Inverse process). Corresponding simulations of the kirigami folding motion from 2D pattern to 3D goal shape are presented (Forward process). The workflow is based on a reciprocal feedback loop including computational design, finite element analysis, dynamic simulation and physical prototyping. Extended from previous research on kirigami geometry, this paper incorporates material properties into the folding process and successfully develops active kirigami models from the DNA scale to human scale. The results presented in this paper provide an attractive method for kirigami design and fabrication with a wide range of scales and applications.","PeriodicalId":211780,"journal":{"name":"Volume 5B: 43rd Mechanisms and Robotics Conference","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127600700","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}
When loaded parallel to the prismatic cells (out-of-plane), honeycombs and re-entrant honeycombs exhibit high initial stiffness and peak force, followed by a force reduction as progressive failure occurs. The high initial peak force and large post-peak force reduction are undesirable for energy absorption purposes. In this study a graded honeycomb structure based on origami is proposed in an effort to lower the peak force, increase the energy absorption capacity and tune the stiffness throughout the loading process. The grading is achieved through a developable origami crease pattern that utilises the typical honeycomb expansion manufacturing technique. The crease pattern has one degree of freedom and is constructed from a repetition of a modified Miura-ori unit. A kinematic study of the crease pattern is completed, highlighting the simple geometric parameters that can be altered to tune the structure. Quasi-static numerical simulations are then used to investigate the interaction between these simple geometric parameters, the energy absorption capacity and the stiffness throughout the loading process. Compared to honeycomb and re-entrant honeycomb tubes, it has been found that a reduction in the peak force, increase in energy absorption capacity and tunable stiffness can be achieved.
{"title":"Graded Origami Honeycomb Tube for Energy Absorption","authors":"L. D. Waal, Z. You","doi":"10.1115/detc2019-97898","DOIUrl":"https://doi.org/10.1115/detc2019-97898","url":null,"abstract":"\u0000 When loaded parallel to the prismatic cells (out-of-plane), honeycombs and re-entrant honeycombs exhibit high initial stiffness and peak force, followed by a force reduction as progressive failure occurs. The high initial peak force and large post-peak force reduction are undesirable for energy absorption purposes. In this study a graded honeycomb structure based on origami is proposed in an effort to lower the peak force, increase the energy absorption capacity and tune the stiffness throughout the loading process. The grading is achieved through a developable origami crease pattern that utilises the typical honeycomb expansion manufacturing technique. The crease pattern has one degree of freedom and is constructed from a repetition of a modified Miura-ori unit. A kinematic study of the crease pattern is completed, highlighting the simple geometric parameters that can be altered to tune the structure. Quasi-static numerical simulations are then used to investigate the interaction between these simple geometric parameters, the energy absorption capacity and the stiffness throughout the loading process. Compared to honeycomb and re-entrant honeycomb tubes, it has been found that a reduction in the peak force, increase in energy absorption capacity and tunable stiffness can be achieved.","PeriodicalId":211780,"journal":{"name":"Volume 5B: 43rd Mechanisms and Robotics Conference","volume":"601 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122941425","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}
Recent studies have revealed that the type/number of operation modes of a parallel manipulator (PM) may vary with the link parameters of the PM. However, current research on the impact of link parameters on the type/number of operation modes of a PM is usually based on intuition. This paper deals with the systematic classification of a 3-RER PM. The 3-RER PM is composed of a base and a moving platform connected by three RER legs, each of which is a serial kinematic chain composed of a revolute (R) joint, a planar (E) joint and an R joint in sequence. The axes of the R joints on the base (or moving platform) are all parallel. At first, a set of constraint equations of the 3-RER PM is first derived. Then using a method called Gröbner cover to calculate the comprehensive Gröbner system of parametric polynomial systems, the 3-RER PM is classified into 21 types. The operation modes of all the types of 3-RER PMs are determined using primary decomposition of ideals. Besides the two 4-DOF (degree-of-freedom) 3T1R operation modes, different types of 3-RER PMs may have up to two more 3-DOF or other types of 4-DOF operation modes. This work is the first systematic study on the impact of link parameters on the operation modes of the 3-RER PM and will contribute to the design and control of 3-RER PMs and research on multi-mode (or reconfigurable) PMs.
{"title":"Classification of a Class of 3-RER Parallel Manipulators Using Gröbner Cover and Primary Decomposition of Ideals","authors":"X. Kong","doi":"10.1115/detc2019-98057","DOIUrl":"https://doi.org/10.1115/detc2019-98057","url":null,"abstract":"\u0000 Recent studies have revealed that the type/number of operation modes of a parallel manipulator (PM) may vary with the link parameters of the PM. However, current research on the impact of link parameters on the type/number of operation modes of a PM is usually based on intuition. This paper deals with the systematic classification of a 3-RER PM. The 3-RER PM is composed of a base and a moving platform connected by three RER legs, each of which is a serial kinematic chain composed of a revolute (R) joint, a planar (E) joint and an R joint in sequence. The axes of the R joints on the base (or moving platform) are all parallel. At first, a set of constraint equations of the 3-RER PM is first derived. Then using a method called Gröbner cover to calculate the comprehensive Gröbner system of parametric polynomial systems, the 3-RER PM is classified into 21 types. The operation modes of all the types of 3-RER PMs are determined using primary decomposition of ideals. Besides the two 4-DOF (degree-of-freedom) 3T1R operation modes, different types of 3-RER PMs may have up to two more 3-DOF or other types of 4-DOF operation modes. This work is the first systematic study on the impact of link parameters on the operation modes of the 3-RER PM and will contribute to the design and control of 3-RER PMs and research on multi-mode (or reconfigurable) PMs.","PeriodicalId":211780,"journal":{"name":"Volume 5B: 43rd Mechanisms and Robotics Conference","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124306620","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}
Benjamin D. Shuch, Taha Shafa, E. Rogers, Daniel M. Aukes
In this article we present a low-cost, two degree-of-freedom laminate robot transmission for legged locomotion applications. This transmission is specifically applied in the design of a quadrupedal robot, and has the potential to be used in other multi-legged systems. It offers a complex control space with a variety of different programmable gait trajectories, while leveraging low-cost linkages made using laminate approaches. The two-degree-of-freedom kinematics of the leg are subsequently modeled in Python, and the workspace of the robot is then experimentally verified on an initial quadrupedal design. Critical design considerations include the laminate design, the rigidity of the materials that make up the laminate, and the range of motion the device can undergo.
{"title":"Design of a Two DOF Laminate Leg Transmission for Creating Walking Robot Platforms","authors":"Benjamin D. Shuch, Taha Shafa, E. Rogers, Daniel M. Aukes","doi":"10.1115/detc2019-98100","DOIUrl":"https://doi.org/10.1115/detc2019-98100","url":null,"abstract":"\u0000 In this article we present a low-cost, two degree-of-freedom laminate robot transmission for legged locomotion applications. This transmission is specifically applied in the design of a quadrupedal robot, and has the potential to be used in other multi-legged systems. It offers a complex control space with a variety of different programmable gait trajectories, while leveraging low-cost linkages made using laminate approaches. The two-degree-of-freedom kinematics of the leg are subsequently modeled in Python, and the workspace of the robot is then experimentally verified on an initial quadrupedal design. Critical design considerations include the laminate design, the rigidity of the materials that make up the laminate, and the range of motion the device can undergo.","PeriodicalId":211780,"journal":{"name":"Volume 5B: 43rd Mechanisms and Robotics Conference","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128319667","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}
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