Pub Date : 2021-03-07DOI: 10.1109/ICM46511.2021.9385664
M. Osada, F. Carneiro, Guangwei Zhang, Shunsuke Yoshimoto, A. Yamamoto
Electrostatic film actuators, which are flexible and light-weight linear motors, can possibly realize safe contact between the robot and environments, if adopted for robots. However, the electrostatic film motors have suffered from a technical issue caused by insulating liquid. To generate large force, the actuator must be immersed in insulating liquid. Lower viscosity has been preferred for the liquid, but such liquid can more easily volatilize and causes maintenance problems. To utilize highly-viscous liquid with lower volatility, this paper investigates how highly-viscous liquid affects the thrust force performance. Three silicone oils with different viscosities, as well as one insulating liquid (Fluorinert FC-770 (3M)), were compared in several different conditions. From our analysis, although high viscosity can degrades the force performance due to drag, the results suggested that the highly-viscous oil in the gap was moved by electrostatic force, and thus the viscosity does not always degrade the thrust force. It was also confirmed that in some particular conditions, the use of highly-viscous oil can even enhance the thrust force. On the other hand, highly-viscous oil degrades the backdrivability of the actuator while it is at rest, meaning that there is a trade-off between the force enhancement, volatility, and backdrivability.
{"title":"Effect of insulating liquid on thrust force of a synchronous electrostatic film actuator","authors":"M. Osada, F. Carneiro, Guangwei Zhang, Shunsuke Yoshimoto, A. Yamamoto","doi":"10.1109/ICM46511.2021.9385664","DOIUrl":"https://doi.org/10.1109/ICM46511.2021.9385664","url":null,"abstract":"Electrostatic film actuators, which are flexible and light-weight linear motors, can possibly realize safe contact between the robot and environments, if adopted for robots. However, the electrostatic film motors have suffered from a technical issue caused by insulating liquid. To generate large force, the actuator must be immersed in insulating liquid. Lower viscosity has been preferred for the liquid, but such liquid can more easily volatilize and causes maintenance problems. To utilize highly-viscous liquid with lower volatility, this paper investigates how highly-viscous liquid affects the thrust force performance. Three silicone oils with different viscosities, as well as one insulating liquid (Fluorinert FC-770 (3M)), were compared in several different conditions. From our analysis, although high viscosity can degrades the force performance due to drag, the results suggested that the highly-viscous oil in the gap was moved by electrostatic force, and thus the viscosity does not always degrade the thrust force. It was also confirmed that in some particular conditions, the use of highly-viscous oil can even enhance the thrust force. On the other hand, highly-viscous oil degrades the backdrivability of the actuator while it is at rest, meaning that there is a trade-off between the force enhancement, volatility, and backdrivability.","PeriodicalId":373423,"journal":{"name":"2021 IEEE International Conference on Mechatronics (ICM)","volume":"31 11","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120995342","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}
Pub Date : 2021-03-07DOI: 10.1109/ICM46511.2021.9385702
Donggyun Jung, F. Asano
This paper introduces the telescopic-legged model, which can generate stable walking gait on a low friction road surface by making asymmetric impact posture. First, we introduce an 8-DOF telescopic-legged model, and describe the equation of motion and design a control system. Second, we investigate the possibility of stable gait generation on a low friction road surface with changes the target control period and the impact posture. Third, we analyze the performance of the converged walking and the pattern of gait generation by changing impact posture. Finally, we discuss the results and future works.
{"title":"Stable Gait Generation on a Low Friction Road Surface by Making Impact Posture Asymmetric","authors":"Donggyun Jung, F. Asano","doi":"10.1109/ICM46511.2021.9385702","DOIUrl":"https://doi.org/10.1109/ICM46511.2021.9385702","url":null,"abstract":"This paper introduces the telescopic-legged model, which can generate stable walking gait on a low friction road surface by making asymmetric impact posture. First, we introduce an 8-DOF telescopic-legged model, and describe the equation of motion and design a control system. Second, we investigate the possibility of stable gait generation on a low friction road surface with changes the target control period and the impact posture. Third, we analyze the performance of the converged walking and the pattern of gait generation by changing impact posture. Finally, we discuss the results and future works.","PeriodicalId":373423,"journal":{"name":"2021 IEEE International Conference on Mechatronics (ICM)","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125903275","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}
Pub Date : 2021-03-07DOI: 10.1109/ICM46511.2021.9385659
Jiayu Wang, Chuxiong Hu, Yu Zhu
Modular robots have the ability to perform versatile locomotion with a high diversity of morphologies. However, designing robust locomotion gaits for arbitrary robot morphologies remains exceptionally challenging. In this paper, a two-level hierarchical locomotion framework is presented for addressing modular robot locomotion tasks. The framework combines a central pattern generator controller (CPG) with a neural network trained by deep reinforcement learning. First, the low-level CPG controllers are learned by offline optimization and generate robust straight walking gaits. Second, a high-level neural network is then learned using deep reinforcement learning via trial-and-errors. The high-level learned controller can modulate the low-level CPG parameters based on online inputs including robot states and user commands. Simulation experiments are employed on a 3D modular robot. The results show that the proposed method achieves better overall performance than the baseline methods on different locomotion skills including straight walking, velocity tracking, and circular turning. Simulation results confirm the effectiveness and robustness of the proposed method.
{"title":"Hierarchical Gait Generation for Modular Robots Using Deep Reinforcement Learning","authors":"Jiayu Wang, Chuxiong Hu, Yu Zhu","doi":"10.1109/ICM46511.2021.9385659","DOIUrl":"https://doi.org/10.1109/ICM46511.2021.9385659","url":null,"abstract":"Modular robots have the ability to perform versatile locomotion with a high diversity of morphologies. However, designing robust locomotion gaits for arbitrary robot morphologies remains exceptionally challenging. In this paper, a two-level hierarchical locomotion framework is presented for addressing modular robot locomotion tasks. The framework combines a central pattern generator controller (CPG) with a neural network trained by deep reinforcement learning. First, the low-level CPG controllers are learned by offline optimization and generate robust straight walking gaits. Second, a high-level neural network is then learned using deep reinforcement learning via trial-and-errors. The high-level learned controller can modulate the low-level CPG parameters based on online inputs including robot states and user commands. Simulation experiments are employed on a 3D modular robot. The results show that the proposed method achieves better overall performance than the baseline methods on different locomotion skills including straight walking, velocity tracking, and circular turning. Simulation results confirm the effectiveness and robustness of the proposed method.","PeriodicalId":373423,"journal":{"name":"2021 IEEE International Conference on Mechatronics (ICM)","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126169328","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}
Pub Date : 2021-03-07DOI: 10.1109/ICM46511.2021.9385689
F. Asano
This paper discusses modeling of a legged robot for stable limit cycle walking on a floating island and motion control method focusing on its center of mass (COM). First, we develop a mathematical model that integrates a 6-DOF robot and a floating island, and design the control input for achieving output following. Second, we conduct a test simulation by using simple desired trajectories of the COM, and discuss the problem with undesirable behavior of the generated ground reaction forces. Furthermore, we introduce fifth-order functions of time to smoothly control the COM motion and generate the preferred resultant behavior of the ground reaction forces.
{"title":"Modeling and Control of Stable Limit Cycle Walking on Floating Island","authors":"F. Asano","doi":"10.1109/ICM46511.2021.9385689","DOIUrl":"https://doi.org/10.1109/ICM46511.2021.9385689","url":null,"abstract":"This paper discusses modeling of a legged robot for stable limit cycle walking on a floating island and motion control method focusing on its center of mass (COM). First, we develop a mathematical model that integrates a 6-DOF robot and a floating island, and design the control input for achieving output following. Second, we conduct a test simulation by using simple desired trajectories of the COM, and discuss the problem with undesirable behavior of the generated ground reaction forces. Furthermore, we introduce fifth-order functions of time to smoothly control the COM motion and generate the preferred resultant behavior of the ground reaction forces.","PeriodicalId":373423,"journal":{"name":"2021 IEEE International Conference on Mechatronics (ICM)","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115176922","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}
Pub Date : 2021-03-07DOI: 10.1109/ICM46511.2021.9385683
S. Kimura, T. Nozaki, T. Murakami
This paper proposes a bilateral control system implementing an admittance control system. Bilateral control system realizes teleoperation of a remote robot with a sense of touch. We focus on an admittance-based bilateral control system, which needs only two communication channels and has almost the same control performance as an acceleration-based bilateral control system, which is one of the highest transparent teleoperation systems. However, the conventional admittance-based system assumes an ideal communication situation where there is no communication time delay and no packet loss and has possible to increase position error as time goes on in practical use. The proposed admittance-based system achieves the same control performance as the conventional structure without increasing position error even if there is a communication delay. The validity of the proposed system is confirmed through simulations and experiments.
{"title":"Admittance Control-based Bilateral Control System Considering Position Error","authors":"S. Kimura, T. Nozaki, T. Murakami","doi":"10.1109/ICM46511.2021.9385683","DOIUrl":"https://doi.org/10.1109/ICM46511.2021.9385683","url":null,"abstract":"This paper proposes a bilateral control system implementing an admittance control system. Bilateral control system realizes teleoperation of a remote robot with a sense of touch. We focus on an admittance-based bilateral control system, which needs only two communication channels and has almost the same control performance as an acceleration-based bilateral control system, which is one of the highest transparent teleoperation systems. However, the conventional admittance-based system assumes an ideal communication situation where there is no communication time delay and no packet loss and has possible to increase position error as time goes on in practical use. The proposed admittance-based system achieves the same control performance as the conventional structure without increasing position error even if there is a communication delay. The validity of the proposed system is confirmed through simulations and experiments.","PeriodicalId":373423,"journal":{"name":"2021 IEEE International Conference on Mechatronics (ICM)","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121731553","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}
Pub Date : 2021-03-07DOI: 10.1109/ICM46511.2021.9385600
Toshihiro Ueki, S. Sakaino, T. Tsuji
Force restraint in contact-rich tasks with robots is vital in order to avoid breaking objects. Impedance/admittance controls are effective for achieving the restraint; however, they require adjustment of the kinematic impedance, which may induce instability. We proposed a force restrain method while PD controller is used for avoiding unstable robot behavior. This method alters position command in case the robot may give extreme force which leads to damaging objects. This method expands the trajectory planning and motion generation area practically because it can be executed under the condition that the controller autonomously restrains excessive force. To examine the effectiveness of the proposed method, we experimented with contact and detach motion in 1- and 2- DoF translational directions.
{"title":"Force restrained control to extend flexibility of trajectory planning","authors":"Toshihiro Ueki, S. Sakaino, T. Tsuji","doi":"10.1109/ICM46511.2021.9385600","DOIUrl":"https://doi.org/10.1109/ICM46511.2021.9385600","url":null,"abstract":"Force restraint in contact-rich tasks with robots is vital in order to avoid breaking objects. Impedance/admittance controls are effective for achieving the restraint; however, they require adjustment of the kinematic impedance, which may induce instability. We proposed a force restrain method while PD controller is used for avoiding unstable robot behavior. This method alters position command in case the robot may give extreme force which leads to damaging objects. This method expands the trajectory planning and motion generation area practically because it can be executed under the condition that the controller autonomously restrains excessive force. To examine the effectiveness of the proposed method, we experimented with contact and detach motion in 1- and 2- DoF translational directions.","PeriodicalId":373423,"journal":{"name":"2021 IEEE International Conference on Mechatronics (ICM)","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131126608","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}
Pub Date : 2021-03-07DOI: 10.1109/ICM46511.2021.9385607
Mohammad Joula, S. Dilibal, J. Owusu-Danquah
Li-ion battery packs are used in varied industrial fields, such as automotive, drone, and e-bike industries. Low temperature insulation and high temperature heat conduction are required for an ideal thermal management of battery pack. In this study, an autonomous system design is developed for a smart adaptronic Battery Thermal Management System (BTMS). We proposed two different nickel-titanium (NiTi) shape memory alloy (SMA)-actuated smart adaptronic BTMSs. The actuation strain of the system is examined using a computational NiTi shape memory alloy model for material selection. The model results showed that an actuation strain of 3.8 % can be obtained for the operating temperatures range between 15°C and 80 °C. The model results is used to unveil the required properties of NiTi SMA wire. The proposed adaptronic BTMS design solutions can create competitive advantages with their compact, low-cost, and lightweight structures in industry.
{"title":"Smart Adaptronic Thermal Management System Designs for The Li-ion Battery Packs","authors":"Mohammad Joula, S. Dilibal, J. Owusu-Danquah","doi":"10.1109/ICM46511.2021.9385607","DOIUrl":"https://doi.org/10.1109/ICM46511.2021.9385607","url":null,"abstract":"Li-ion battery packs are used in varied industrial fields, such as automotive, drone, and e-bike industries. Low temperature insulation and high temperature heat conduction are required for an ideal thermal management of battery pack. In this study, an autonomous system design is developed for a smart adaptronic Battery Thermal Management System (BTMS). We proposed two different nickel-titanium (NiTi) shape memory alloy (SMA)-actuated smart adaptronic BTMSs. The actuation strain of the system is examined using a computational NiTi shape memory alloy model for material selection. The model results showed that an actuation strain of 3.8 % can be obtained for the operating temperatures range between 15°C and 80 °C. The model results is used to unveil the required properties of NiTi SMA wire. The proposed adaptronic BTMS design solutions can create competitive advantages with their compact, low-cost, and lightweight structures in industry.","PeriodicalId":373423,"journal":{"name":"2021 IEEE International Conference on Mechatronics (ICM)","volume":"35 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132996112","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}
Pub Date : 2021-03-07DOI: 10.1109/ICM46511.2021.9385667
S. Yabui, H. Inoue, T. Inoue
In electrical plants, rotating machines have to maintain power supply for our life. Rotating machines such as turbines are main component of the electrical plants. Stability performance of the rotating machines is important design point. Rotordynamic force influences the stability performance, and the rotordynamic forces should be evaluated in the development. Theoretical analysis is difficult to evaluate the rotordynamic forces accurately, because the characteristic is complex due to coupling with mechanical and fluid dynamics. On the other hand, direct measurement of rotordynamic forces has a problem, because the measurement condition, namely the rotating speed, the whirling orbit of a rotor is difficult to realize in a test bench. This study proposes a control system to improve the performance of a active magnetic bearing in the test bench. The control system can realize the measurement condition accurately, and the rotordynamic forces can be measured at various frequencies simultaneously. In the feasibility study, the measured rotordynamic forces by using the proposed control system were matched to the simulation data.
{"title":"Control Performance Improvement of Excitation System with Active Magnetic Bearing for Measurement of Rotordynamic Forces","authors":"S. Yabui, H. Inoue, T. Inoue","doi":"10.1109/ICM46511.2021.9385667","DOIUrl":"https://doi.org/10.1109/ICM46511.2021.9385667","url":null,"abstract":"In electrical plants, rotating machines have to maintain power supply for our life. Rotating machines such as turbines are main component of the electrical plants. Stability performance of the rotating machines is important design point. Rotordynamic force influences the stability performance, and the rotordynamic forces should be evaluated in the development. Theoretical analysis is difficult to evaluate the rotordynamic forces accurately, because the characteristic is complex due to coupling with mechanical and fluid dynamics. On the other hand, direct measurement of rotordynamic forces has a problem, because the measurement condition, namely the rotating speed, the whirling orbit of a rotor is difficult to realize in a test bench. This study proposes a control system to improve the performance of a active magnetic bearing in the test bench. The control system can realize the measurement condition accurately, and the rotordynamic forces can be measured at various frequencies simultaneously. In the feasibility study, the measured rotordynamic forces by using the proposed control system were matched to the simulation data.","PeriodicalId":373423,"journal":{"name":"2021 IEEE International Conference on Mechatronics (ICM)","volume":"131 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127832355","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}
Pub Date : 2021-03-07DOI: 10.1109/ICM46511.2021.9385673
Kosuke Matsui, H. Kajiwara, S. Ishigaki
In this paper, a sway control algorithm is proposed, which can be implemented in a crane system where the acceleration cannot be controlled continuously due to restrictions on the trolley drive system. Our algorithm approximates the feedforward (FF) control input by means of the time-polynomial method (FFT) using the PWM control input, and recalculates the FFT control input with a constant period so that the residual sway is suppressed. This algorithm is called the “Update type FF control using the time-polynomial method (UFFT).” The effectiveness of the UFFT algorithm is verified through multi-degree-of-freedom rigid body simulations, and it is confirmed that the residual sway is suppressed by increasing the update frequency of the FF control input.
{"title":"Feedforward Control Design Methodology for a Crane System with Restrictions on Drive System","authors":"Kosuke Matsui, H. Kajiwara, S. Ishigaki","doi":"10.1109/ICM46511.2021.9385673","DOIUrl":"https://doi.org/10.1109/ICM46511.2021.9385673","url":null,"abstract":"In this paper, a sway control algorithm is proposed, which can be implemented in a crane system where the acceleration cannot be controlled continuously due to restrictions on the trolley drive system. Our algorithm approximates the feedforward (FF) control input by means of the time-polynomial method (FFT) using the PWM control input, and recalculates the FFT control input with a constant period so that the residual sway is suppressed. This algorithm is called the “Update type FF control using the time-polynomial method (UFFT).” The effectiveness of the UFFT algorithm is verified through multi-degree-of-freedom rigid body simulations, and it is confirmed that the residual sway is suppressed by increasing the update frequency of the FF control input.","PeriodicalId":373423,"journal":{"name":"2021 IEEE International Conference on Mechatronics (ICM)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115419116","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}
Many studies have been recently exploited to discuss the path following control algorithms for automated vehicles using various control techniques. However, path following algorithm considering the possibility of automated vehicles with rear wheel steering (RWS) is still less investigated. In this study, we implemented nonlinear model predictive control (NMPC) on a passenger vehicle with active RWS for path following. The controller was compared to two other variations of NMPC where the rear steering angle is proportional to the front or fixed to zero. Simulation results suggested that the proposed controller outperforms the other two variations and the baseline controllers (Stanley and LQR) in terms of accuracy and responsiveness.
{"title":"MPC-based Path Following Design for Automated Vehicles with Rear Wheel Steering","authors":"Chuanyang Yu, Yanggu Zheng, Barys Shyrokau, Valentin Ivanov","doi":"10.1109/ICM46511.2021.9385606","DOIUrl":"https://doi.org/10.1109/ICM46511.2021.9385606","url":null,"abstract":"Many studies have been recently exploited to discuss the path following control algorithms for automated vehicles using various control techniques. However, path following algorithm considering the possibility of automated vehicles with rear wheel steering (RWS) is still less investigated. In this study, we implemented nonlinear model predictive control (NMPC) on a passenger vehicle with active RWS for path following. The controller was compared to two other variations of NMPC where the rear steering angle is proportional to the front or fixed to zero. Simulation results suggested that the proposed controller outperforms the other two variations and the baseline controllers (Stanley and LQR) in terms of accuracy and responsiveness.","PeriodicalId":373423,"journal":{"name":"2021 IEEE International Conference on Mechatronics (ICM)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117140802","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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