Pub Date : 2010-12-17DOI: 10.1109/ICCAS.2010.5670325
N. Fatehi, A. Akbarimajd, M. Asadpour
Zero moment point has been usually employed for balance keeping and walking analysis of active biped robots with bent knees, while balance and walking stability analysis of passive robots has been done using cyclic analysis approaches. While the problem in general is common, the two approaches have been separated in the literature for two different classes of passivity-based and ZMP-based robots. In this paper we have made a ZMP analysis for a passivity-based biped robot. The robot has been simulated using MSC Adams and Matlab/Simulink and a stable walking is achieved for a defined walking policy which is based on passivity-based walking with hips and ankles actuated and knee joints considered passive. The trajectory of ZMP is extracted and discussed during a stable walking. The role of Achill's spring on ZMP is discussed and the overall profile of ZMP trajectory and its changes at specific crucial events, like knee strike and heel strike, is analyzed.
{"title":"ZMP analysis for dynamic walking of a passivity-based biped robot with flat feet","authors":"N. Fatehi, A. Akbarimajd, M. Asadpour","doi":"10.1109/ICCAS.2010.5670325","DOIUrl":"https://doi.org/10.1109/ICCAS.2010.5670325","url":null,"abstract":"Zero moment point has been usually employed for balance keeping and walking analysis of active biped robots with bent knees, while balance and walking stability analysis of passive robots has been done using cyclic analysis approaches. While the problem in general is common, the two approaches have been separated in the literature for two different classes of passivity-based and ZMP-based robots. In this paper we have made a ZMP analysis for a passivity-based biped robot. The robot has been simulated using MSC Adams and Matlab/Simulink and a stable walking is achieved for a defined walking policy which is based on passivity-based walking with hips and ankles actuated and knee joints considered passive. The trajectory of ZMP is extracted and discussed during a stable walking. The role of Achill's spring on ZMP is discussed and the overall profile of ZMP trajectory and its changes at specific crucial events, like knee strike and heel strike, is analyzed.","PeriodicalId":158687,"journal":{"name":"ICCAS 2010","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130576273","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 : 2010-12-17DOI: 10.1109/ICCAS.2010.5669813
Y. Shao, W. Tu, F. Gu
An internal impact usually happens when there is a small defect in one part of rolling bearings. The Fault signal from this impact is always masked by different noises such as strong vibrations from other parts and the random noise of instrumentation, which makes it difficult to extract an accurate feature signal for early fault diagnosis. In this paper, a simulation study is conducted using the method of finite element analysis (FEA) to understand the vibration characteristics from the small impact. The vibration responses have been modelled based on a typical bearing assembly. Common faults including outer ring defect, inner ring defect and rolling ball defect are simulated and their vibration responses are compared between different faults and at different locations in the bearing housing. The results obtained have shown that under the same defect size, the vibration from the outer ring is the highest whereas that from the rolling ball is the smallest. In addition the vibration close to the mounting hole attenuates considerably compared to that close to outer ring. These findings provide fundamental information to place vibration sensors and to analyse vibration signals.
{"title":"A simulation study of defects in a rolling element bearing using FEA","authors":"Y. Shao, W. Tu, F. Gu","doi":"10.1109/ICCAS.2010.5669813","DOIUrl":"https://doi.org/10.1109/ICCAS.2010.5669813","url":null,"abstract":"An internal impact usually happens when there is a small defect in one part of rolling bearings. The Fault signal from this impact is always masked by different noises such as strong vibrations from other parts and the random noise of instrumentation, which makes it difficult to extract an accurate feature signal for early fault diagnosis. In this paper, a simulation study is conducted using the method of finite element analysis (FEA) to understand the vibration characteristics from the small impact. The vibration responses have been modelled based on a typical bearing assembly. Common faults including outer ring defect, inner ring defect and rolling ball defect are simulated and their vibration responses are compared between different faults and at different locations in the bearing housing. The results obtained have shown that under the same defect size, the vibration from the outer ring is the highest whereas that from the rolling ball is the smallest. In addition the vibration close to the mounting hole attenuates considerably compared to that close to outer ring. These findings provide fundamental information to place vibration sensors and to analyse vibration signals.","PeriodicalId":158687,"journal":{"name":"ICCAS 2010","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123968993","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 : 2010-12-17DOI: 10.1109/ICCAS.2010.5670274
Jeong-Hoon Lee, Kyung-Soo Kim, Soohyun Kim
This paper describes that a sliding mode control of a discharge air temperature is applied in automotive HVAC. The sliding mode control is suggested to improve the response time and disturbance reduction in a variety of climate and vehicle conditions. Automotive HVAC system is modeled as four parts - the blower, heat exchanger, air mixing, and duct sensor transportation delay under the assumption of dry air, adiabatic process, the fully developed air mixing process. The weight factor in time delay and lag model was adapted to reduce nonlinear modeling and approximation error. Sliding mode control is better than PI control from the point of view of settling time in this system.
{"title":"A sliding mode control of discharge air temperature in automotive HVAC using nonlinear sliding surface in input-delay system","authors":"Jeong-Hoon Lee, Kyung-Soo Kim, Soohyun Kim","doi":"10.1109/ICCAS.2010.5670274","DOIUrl":"https://doi.org/10.1109/ICCAS.2010.5670274","url":null,"abstract":"This paper describes that a sliding mode control of a discharge air temperature is applied in automotive HVAC. The sliding mode control is suggested to improve the response time and disturbance reduction in a variety of climate and vehicle conditions. Automotive HVAC system is modeled as four parts - the blower, heat exchanger, air mixing, and duct sensor transportation delay under the assumption of dry air, adiabatic process, the fully developed air mixing process. The weight factor in time delay and lag model was adapted to reduce nonlinear modeling and approximation error. Sliding mode control is better than PI control from the point of view of settling time in this system.","PeriodicalId":158687,"journal":{"name":"ICCAS 2010","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123349180","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 : 2010-12-17DOI: 10.1109/ICCAS.2010.5669796
Y. Ki, I. Oh, Jaehan Jeon, Jaeseung Chun, Hyun-Sik Ahn
In this paper, a new algorithm which considers the hysteresis by backlash to estimate clamping force from motor rotor position is proposed and its usefulness is shown with comparison of previous algorithm. In order to set the zero point of curve of clamping force versus motor rotor position using motor current, a new detection strategy for the contact point of the brake pads and the brake disc is developed. Additionally, Brake pad temperature adaptation method is also proposed to improve performance of clamping force estimation algorithm. EMB model is developed and validated using MATLAB/Simulink and the performance of the EMB controller based on estimation algorithm is shown by the simulation results.
{"title":"A new type of clamping force estimator for electromechanical brake systems","authors":"Y. Ki, I. Oh, Jaehan Jeon, Jaeseung Chun, Hyun-Sik Ahn","doi":"10.1109/ICCAS.2010.5669796","DOIUrl":"https://doi.org/10.1109/ICCAS.2010.5669796","url":null,"abstract":"In this paper, a new algorithm which considers the hysteresis by backlash to estimate clamping force from motor rotor position is proposed and its usefulness is shown with comparison of previous algorithm. In order to set the zero point of curve of clamping force versus motor rotor position using motor current, a new detection strategy for the contact point of the brake pads and the brake disc is developed. Additionally, Brake pad temperature adaptation method is also proposed to improve performance of clamping force estimation algorithm. EMB model is developed and validated using MATLAB/Simulink and the performance of the EMB controller based on estimation algorithm is shown by the simulation results.","PeriodicalId":158687,"journal":{"name":"ICCAS 2010","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123503837","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 : 2010-12-17DOI: 10.1109/ICCAS.2010.5670275
Seul Jung, Kwang Ki Shim
This paper presents a case study of a class project for Junior level students in the curriculum of Mechatronics Engineering. As a class project of a sensor and signal processing class, a team of two students is required to build two line tracers, a master and a slave line tracer. The master line tracer is same as the line tracer that follows the line, but the slave line tracer is required to follow the master with limitation of sensors to follow the front master. The slave does not have communication with the master and any sensors to detect the line. The slave has only the distance sensor to detect the master. At the end of the semester, a master-slave line tracer competition is held to evaluate student grade for the class.
{"title":"A case study as a class project of master-slave line tracer competition for undergraduate student education","authors":"Seul Jung, Kwang Ki Shim","doi":"10.1109/ICCAS.2010.5670275","DOIUrl":"https://doi.org/10.1109/ICCAS.2010.5670275","url":null,"abstract":"This paper presents a case study of a class project for Junior level students in the curriculum of Mechatronics Engineering. As a class project of a sensor and signal processing class, a team of two students is required to build two line tracers, a master and a slave line tracer. The master line tracer is same as the line tracer that follows the line, but the slave line tracer is required to follow the master with limitation of sensors to follow the front master. The slave does not have communication with the master and any sensors to detect the line. The slave has only the distance sensor to detect the master. At the end of the semester, a master-slave line tracer competition is held to evaluate student grade for the class.","PeriodicalId":158687,"journal":{"name":"ICCAS 2010","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114237837","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 : 2010-12-17DOI: 10.1109/ICCAS.2010.5669661
Jong-Kyu Oh, Chan-Ho Lee, Sang-Hun Lee, Sung-Hyun Jung, Da-Sol Kim, Sukhan Lee
This paper proposes a general-purpose structured-light sensor based bin-picking system. At first, to determine the workpiece to be picked, a geometric pattern matching (GPM) method with respect to the 2D image is applied. A structured-light sensor with gray-coded patterns is employed to get the reliable 3D range image for the pick-up candidate. The pose of the object is acquired by just comparing the 3D point cloud between models in database and a range image acquired from the structured-light sensor through iterative closest point (ICP) algorithm in contrast with the conventional bin-picking systems which require complete knowledge of the object. Through experiments on an industrial workpiece, we validate that the proposed vision system accurately measures the 3D pose of complex objects.
{"title":"Development of a structured-light sensor based bin-picking system using ICP algorithm","authors":"Jong-Kyu Oh, Chan-Ho Lee, Sang-Hun Lee, Sung-Hyun Jung, Da-Sol Kim, Sukhan Lee","doi":"10.1109/ICCAS.2010.5669661","DOIUrl":"https://doi.org/10.1109/ICCAS.2010.5669661","url":null,"abstract":"This paper proposes a general-purpose structured-light sensor based bin-picking system. At first, to determine the workpiece to be picked, a geometric pattern matching (GPM) method with respect to the 2D image is applied. A structured-light sensor with gray-coded patterns is employed to get the reliable 3D range image for the pick-up candidate. The pose of the object is acquired by just comparing the 3D point cloud between models in database and a range image acquired from the structured-light sensor through iterative closest point (ICP) algorithm in contrast with the conventional bin-picking systems which require complete knowledge of the object. Through experiments on an industrial workpiece, we validate that the proposed vision system accurately measures the 3D pose of complex objects.","PeriodicalId":158687,"journal":{"name":"ICCAS 2010","volume":"162 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114528412","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 : 2010-12-17DOI: 10.1109/ICCAS.2010.5669946
Wonhee Kim, Donghoon Shin, D. Gang, C. Chung
Proportional-integral-derivative (PID) controls have been widely used for Sawyer motors. The electrical dynamics are generally neglected in general PIDs control since the electrical dynamics are faster than the mechanical dynamics. However, when the current control is used, the phase currents are reduced by back-emf and have the phase lags due to inductances. Thus, the electrical dynamics should be considered to improve the performance of PID control. In this paper, Lyapunov-based microstepping control of Sawyer motors with PID control is developed for improved performance of PID control. The proposed method consists of PID and Lyapunov-based controller. PID controllers make the desired forces and torque to track the position profiles of x and y with regulation of yaw. And the commutation scheme from the desired forces and torque to the desired phase currents are used. For the design of Lyapunov-based control, the stabilities of the equilibrium points are studied using Lyapunov method. Then, Lyapunov-based control is designed to compensate back-emfs and phase lags. Furthermore, the proposed method guarantees the exponential stabilities of desired currents for PID control. And, the closed-loop system is analyzed. The proposed method considering the electrical dynamics is designed without any coordinate transformation. Therefore, it could reduce the commutation delay. Simulation results show that the tracking performance of PID controller is improved by the proposed method.
{"title":"Lyapunov-based microstepping control of Sawyer motors with PID control","authors":"Wonhee Kim, Donghoon Shin, D. Gang, C. Chung","doi":"10.1109/ICCAS.2010.5669946","DOIUrl":"https://doi.org/10.1109/ICCAS.2010.5669946","url":null,"abstract":"Proportional-integral-derivative (PID) controls have been widely used for Sawyer motors. The electrical dynamics are generally neglected in general PIDs control since the electrical dynamics are faster than the mechanical dynamics. However, when the current control is used, the phase currents are reduced by back-emf and have the phase lags due to inductances. Thus, the electrical dynamics should be considered to improve the performance of PID control. In this paper, Lyapunov-based microstepping control of Sawyer motors with PID control is developed for improved performance of PID control. The proposed method consists of PID and Lyapunov-based controller. PID controllers make the desired forces and torque to track the position profiles of x and y with regulation of yaw. And the commutation scheme from the desired forces and torque to the desired phase currents are used. For the design of Lyapunov-based control, the stabilities of the equilibrium points are studied using Lyapunov method. Then, Lyapunov-based control is designed to compensate back-emfs and phase lags. Furthermore, the proposed method guarantees the exponential stabilities of desired currents for PID control. And, the closed-loop system is analyzed. The proposed method considering the electrical dynamics is designed without any coordinate transformation. Therefore, it could reduce the commutation delay. Simulation results show that the tracking performance of PID controller is improved by the proposed method.","PeriodicalId":158687,"journal":{"name":"ICCAS 2010","volume":"600 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116285039","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 : 2010-12-17DOI: 10.1109/ICCAS.2010.5670222
S. Razali, K. Watanabe, S. Maeyama, K. Izumi
The unscented Kalman filter (UKF) has become a new technique used in a number of nonlinear estimation problems to overcome the limitation of Taylor series linearization. It uses a deterministic sampling approach known as sigma points to propagate nonlinear systems and has been discussed in many literature. However, a nonlinear smoothing problem has received less attention than the filtering problem. Therefore, in this article we examine an unscented smoother based on Rauch-Tung-Striebel form for discrete-time dynamic systems. This smoother has advantages available in unscented transformation over approximation by Taylor expansion as well as its benefit in derivative free. To evaluate the performance of this smoother, we compare this algorithm with an extended Rauch-Tung-Striebel algorithm through the simulations of a bearing-only tracking problem.
{"title":"An unscented Rauch-Tung-Striebel smoother for a bearing only tracking problem","authors":"S. Razali, K. Watanabe, S. Maeyama, K. Izumi","doi":"10.1109/ICCAS.2010.5670222","DOIUrl":"https://doi.org/10.1109/ICCAS.2010.5670222","url":null,"abstract":"The unscented Kalman filter (UKF) has become a new technique used in a number of nonlinear estimation problems to overcome the limitation of Taylor series linearization. It uses a deterministic sampling approach known as sigma points to propagate nonlinear systems and has been discussed in many literature. However, a nonlinear smoothing problem has received less attention than the filtering problem. Therefore, in this article we examine an unscented smoother based on Rauch-Tung-Striebel form for discrete-time dynamic systems. This smoother has advantages available in unscented transformation over approximation by Taylor expansion as well as its benefit in derivative free. To evaluate the performance of this smoother, we compare this algorithm with an extended Rauch-Tung-Striebel algorithm through the simulations of a bearing-only tracking problem.","PeriodicalId":158687,"journal":{"name":"ICCAS 2010","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116468489","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 : 2010-12-17DOI: 10.1109/ICCAS.2010.5669922
Y. Mo, Byung-Wook Woo, Yun-Geun Choe, J. Park, M. Lim
The Bolting robot assistance system prevents operator to face dangerous situations. Bolting robot assistance system consists of bolting robot control system and top-view supervisory system. In order to control a bolting robot, Camshift algorithm and circular Hough transform are used. To estimate location of bolt hole, circular Hough transform is used. In order to track a bolt hole, Meanshift and Camshift are used. Camshift operates on color image represented by probability point and applies a non-parametric gradient density called Meanshift algorithm to re-center its operating window. By setting region to search a bolt hole, the algorithm will track the location of the bolt hole. In order to make top-view supervisory system, four cameras are installed at left, right, front and back of the robot. Each image from the camera is used to make the top-view image after correcting distortion. This paper proposes the image processing algorithm which is suitable for top-view supervisory system.
{"title":"Bolting robot assistance system using image processing","authors":"Y. Mo, Byung-Wook Woo, Yun-Geun Choe, J. Park, M. Lim","doi":"10.1109/ICCAS.2010.5669922","DOIUrl":"https://doi.org/10.1109/ICCAS.2010.5669922","url":null,"abstract":"The Bolting robot assistance system prevents operator to face dangerous situations. Bolting robot assistance system consists of bolting robot control system and top-view supervisory system. In order to control a bolting robot, Camshift algorithm and circular Hough transform are used. To estimate location of bolt hole, circular Hough transform is used. In order to track a bolt hole, Meanshift and Camshift are used. Camshift operates on color image represented by probability point and applies a non-parametric gradient density called Meanshift algorithm to re-center its operating window. By setting region to search a bolt hole, the algorithm will track the location of the bolt hole. In order to make top-view supervisory system, four cameras are installed at left, right, front and back of the robot. Each image from the camera is used to make the top-view image after correcting distortion. This paper proposes the image processing algorithm which is suitable for top-view supervisory system.","PeriodicalId":158687,"journal":{"name":"ICCAS 2010","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116470556","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 : 2010-12-17DOI: 10.1109/ICCAS.2010.5670133
Min-Ho Kim, Min-Cheol Lee
Nowadays, the research of the unmanned vehicle robots is increased, especially in the military fields. Some of these robots use path tracking algorithm, so the path generation method is needed. Now we suggest that the path generation method could be used into augmented reality using the B-spline curve equation. Therefore we can make the robot can track the virtual path in real time by obtaining the error distance between the path in the augmented reality and the robot.
{"title":"A path generation method for path tracking algorithms that use the augmented reality","authors":"Min-Ho Kim, Min-Cheol Lee","doi":"10.1109/ICCAS.2010.5670133","DOIUrl":"https://doi.org/10.1109/ICCAS.2010.5670133","url":null,"abstract":"Nowadays, the research of the unmanned vehicle robots is increased, especially in the military fields. Some of these robots use path tracking algorithm, so the path generation method is needed. Now we suggest that the path generation method could be used into augmented reality using the B-spline curve equation. Therefore we can make the robot can track the virtual path in real time by obtaining the error distance between the path in the augmented reality and the robot.","PeriodicalId":158687,"journal":{"name":"ICCAS 2010","volume":"132 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124335822","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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