Pub Date : 2011-05-25DOI: 10.1109/ISAM.2011.5942325
Ming Zhao, Jing Lin, Xiufeng Wang, Y. Liao
The dynamic transmission error of a CNC machine tool affects the manufacturing precision significantly. It may be caused by many factors, such as the geometric error of the transmission parts, the defects on the tooth flank as well as the torsional vibration of running shafts etc. It is very important to locate where the major source is so as to provide a guidance to reduce the transmission error. In this article, the dynamic behavior of the transmission is obtained by using some built-in encoders of a CNC machine tool. Signals obtained from those encoders are the rotating angles of the shafts varying with time. The transmission error can be estimated by using those signals. Some signal processing approaches are established to analyze those signals to locate the error sources. Vibration is one of the most troubling problems encountered in CNC machine tools, this paper also provides an approach for vibration source identification based on the information obtained from the built-in encoders.
{"title":"Dynamic transmission error analysis for a CNC machine tool based on built-in encoders","authors":"Ming Zhao, Jing Lin, Xiufeng Wang, Y. Liao","doi":"10.1109/ISAM.2011.5942325","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942325","url":null,"abstract":"The dynamic transmission error of a CNC machine tool affects the manufacturing precision significantly. It may be caused by many factors, such as the geometric error of the transmission parts, the defects on the tooth flank as well as the torsional vibration of running shafts etc. It is very important to locate where the major source is so as to provide a guidance to reduce the transmission error. In this article, the dynamic behavior of the transmission is obtained by using some built-in encoders of a CNC machine tool. Signals obtained from those encoders are the rotating angles of the shafts varying with time. The transmission error can be estimated by using those signals. Some signal processing approaches are established to analyze those signals to locate the error sources. Vibration is one of the most troubling problems encountered in CNC machine tools, this paper also provides an approach for vibration source identification based on the information obtained from the built-in encoders.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125472821","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942300
G. Reinhart, T. Kirchmeier
The assembly of micro parts is associated with several demands. Most of these parts are highly sensitive to mechanical contact and to applied forces. As a consequence common handling tools proofed to be insufficient. Due to this fact new gripping principles are an urgent demand. Especially a new and upcoming contactless handling principle based on ultrasonic vibrations offers great potentials. This paper shows how the handling technology can be designed for different parts using an expert system, which consists of two subsystems, a neural network and a fuzzy logic model. The first one stores the characteristic process parameters of individual gripper designs and interpolates them for similar grippers. The second one uses the existing hypothesis and expert knowledge in order to estimate the part stability for each parameter combination. In this paper the implementation of the fuzzy logic model is introduced.
{"title":"Fuzzy logic based ultrasonic gripper design for handling small parts","authors":"G. Reinhart, T. Kirchmeier","doi":"10.1109/ISAM.2011.5942300","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942300","url":null,"abstract":"The assembly of micro parts is associated with several demands. Most of these parts are highly sensitive to mechanical contact and to applied forces. As a consequence common handling tools proofed to be insufficient. Due to this fact new gripping principles are an urgent demand. Especially a new and upcoming contactless handling principle based on ultrasonic vibrations offers great potentials. This paper shows how the handling technology can be designed for different parts using an expert system, which consists of two subsystems, a neural network and a fuzzy logic model. The first one stores the characteristic process parameters of individual gripper designs and interpolates them for similar grippers. The second one uses the existing hypothesis and expert knowledge in order to estimate the part stability for each parameter combination. In this paper the implementation of the fuzzy logic model is introduced.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123278620","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942304
Guoqing Yang, Jun Hong, Ning Wang, Linbo Zhu, Yucheng Ding, Zhaohui Yang
Bolted joints including bolts and members act like elastic springs under assembly and operating conditions. The bearing and transferring of the initial preload and the operating force are mainly dependent on the stiffness of both the bolts and their corresponding members. To obtain the deformation mechanism of bolted members, a systematic study on the prediction of the member stiffness and the characterization of the interface contact conditions is developed in this paper. Firstly, a parameterization process is performed to relate all the geometric dimensions of each bolted joint with the corresponding bolt diameter, so the corresponding dimensionless dimensions can be conveniently gotten by dividing the dimensions by the bolt diameter. Based on this, a novel and efficient finite element (FE) model is constructed to simulate the behaviors of bolted joints with different geometrical sizes and material properties. After characterizing the member stiffness, the interface contact characteristics of bolted joints including contact pressure and the dimensionless contact diameter are further identified through special FE post-processing efforts. Finally, a series of semi-apex angles are obtained through an inverse calculation approach in which an author-modified empirical formula is adopted. The calculation results based on the proposed method may be considered as a simple and practical guideline for the design and assembly processes of bolted joints.
{"title":"Member stiffnesses and interface contact characteristics of bolted joints","authors":"Guoqing Yang, Jun Hong, Ning Wang, Linbo Zhu, Yucheng Ding, Zhaohui Yang","doi":"10.1109/ISAM.2011.5942304","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942304","url":null,"abstract":"Bolted joints including bolts and members act like elastic springs under assembly and operating conditions. The bearing and transferring of the initial preload and the operating force are mainly dependent on the stiffness of both the bolts and their corresponding members. To obtain the deformation mechanism of bolted members, a systematic study on the prediction of the member stiffness and the characterization of the interface contact conditions is developed in this paper. Firstly, a parameterization process is performed to relate all the geometric dimensions of each bolted joint with the corresponding bolt diameter, so the corresponding dimensionless dimensions can be conveniently gotten by dividing the dimensions by the bolt diameter. Based on this, a novel and efficient finite element (FE) model is constructed to simulate the behaviors of bolted joints with different geometrical sizes and material properties. After characterizing the member stiffness, the interface contact characteristics of bolted joints including contact pressure and the dimensionless contact diameter are further identified through special FE post-processing efforts. Finally, a series of semi-apex angles are obtained through an inverse calculation approach in which an author-modified empirical formula is adopted. The calculation results based on the proposed method may be considered as a simple and practical guideline for the design and assembly processes of bolted joints.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116750700","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942318
Xuewei Li, K. Cao, Wanhua Zhao, B. Lu, Jun Zhang
With the application of compensation for geometric error and thermal error, static and quasi-static accuracy of machine tools are significantly improved. Whereas, the accompanied disadvantage is the increased motion control error, especially the motion control accuracy in high-speed and ultra high-speed machining. Based on the actual contour measurement and the study of different control strategies for improving contour machining accuracy, this paper proposes an error compensation method for multi-axis machining. To be specific, a contour error model with different input parameters of the machining process needs to be built, and afterwards to be implemented into an open computer numerical control (CNC) system for real time calculation and compensation. Employing a 2-aix machine tool and base on aforementioned method, circular processing experiments with feed rates ranging from 0.5m/min to 10m/min and radiuses ranging from 10mm to 60mm are performed. The range of average radius error is reduced from 0.1mm to 0.006mm. The results demonstrate that high contour accuracy can be maintained even at high speed machining.
{"title":"An error compensation method for multi-axis machining based on the actual contour measurement","authors":"Xuewei Li, K. Cao, Wanhua Zhao, B. Lu, Jun Zhang","doi":"10.1109/ISAM.2011.5942318","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942318","url":null,"abstract":"With the application of compensation for geometric error and thermal error, static and quasi-static accuracy of machine tools are significantly improved. Whereas, the accompanied disadvantage is the increased motion control error, especially the motion control accuracy in high-speed and ultra high-speed machining. Based on the actual contour measurement and the study of different control strategies for improving contour machining accuracy, this paper proposes an error compensation method for multi-axis machining. To be specific, a contour error model with different input parameters of the machining process needs to be built, and afterwards to be implemented into an open computer numerical control (CNC) system for real time calculation and compensation. Employing a 2-aix machine tool and base on aforementioned method, circular processing experiments with feed rates ranging from 0.5m/min to 10m/min and radiuses ranging from 10mm to 60mm are performed. The range of average radius error is reduced from 0.1mm to 0.006mm. The results demonstrate that high contour accuracy can be maintained even at high speed machining.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114353829","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942346
J. Heilala, Jari Montonen, T. Kuula, T. Usenius, Matti Maantila, J. Sillanpaa
Agile production needs a management and evaluation tool for production changes, manufacturing system development, configuration and operations planning. A decision support system based on manufacturing simulation is one suitable solution. The basic idea is to combine the strengths of automatic data analysis, calculations, simulation results with the visual perception and analysis capabilities of the human user, who is doing final decisions. The use of simulation with an easy-to-use graphical user interface provides tools and methods for manufacturing scenario evaluation, scheduling optimization, and production planning even for simulation non-experts. This article shows a user-centric development process for those systems.
{"title":"User-centric development of simulation based manufacturing operation planning and scheduling system","authors":"J. Heilala, Jari Montonen, T. Kuula, T. Usenius, Matti Maantila, J. Sillanpaa","doi":"10.1109/ISAM.2011.5942346","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942346","url":null,"abstract":"Agile production needs a management and evaluation tool for production changes, manufacturing system development, configuration and operations planning. A decision support system based on manufacturing simulation is one suitable solution. The basic idea is to combine the strengths of automatic data analysis, calculations, simulation results with the visual perception and analysis capabilities of the human user, who is doing final decisions. The use of simulation with an easy-to-use graphical user interface provides tools and methods for manufacturing scenario evaluation, scheduling optimization, and production planning even for simulation non-experts. This article shows a user-centric development process for those systems.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"410 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122458614","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942352
Timothy R. Vittor, H. Staab, S. Breisch, S. Soetebier, Thomas Stahl, A. Hackbarth, Soenke Kock
This paper introduces a new gripper concept that is a cornerstone of an investigation how to close the gap between manual assembly and a fully automatic assembly. The proposed gripper is required to handle a wide range of parts that are today assembled manually. The solution needs to be easy to adapt to meet new product variant requirements for low batch production. The solution further aims to achieve a harmless gripping device to operate in shared human environments. To date, prototypes have been built to validate their functionality, and recently completed lifetime tests on key sub-systems have demonstrated their robustness. A number of third generation prototypes have been built and are currently used in pilot application testing. We expect important learnings from applying the prototypes in a production environment.
{"title":"A flexible robotic gripper for automation of assembly tasks: A technology study on a gripper for operation in shared human environments","authors":"Timothy R. Vittor, H. Staab, S. Breisch, S. Soetebier, Thomas Stahl, A. Hackbarth, Soenke Kock","doi":"10.1109/ISAM.2011.5942352","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942352","url":null,"abstract":"This paper introduces a new gripper concept that is a cornerstone of an investigation how to close the gap between manual assembly and a fully automatic assembly. The proposed gripper is required to handle a wide range of parts that are today assembled manually. The solution needs to be easy to adapt to meet new product variant requirements for low batch production. The solution further aims to achieve a harmless gripping device to operate in shared human environments. To date, prototypes have been built to validate their functionality, and recently completed lifetime tests on key sub-systems have demonstrated their robustness. A number of third generation prototypes have been built and are currently used in pilot application testing. We expect important learnings from applying the prototypes in a production environment.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"173 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123757165","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942298
M. Huhtala, A. Rasanen, M. Lohtander, H. Eskelinen, J. Varis
This document is illustration of one real sheet metal product, which manufacturing is really challenging and many problems occur in production. In this paper there is given some point of views, which should be take into consideration before the part can be produced without (or some minimal) problems.
{"title":"DFMA-aspects of sheet metal product in case of low-cost strategy","authors":"M. Huhtala, A. Rasanen, M. Lohtander, H. Eskelinen, J. Varis","doi":"10.1109/ISAM.2011.5942298","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942298","url":null,"abstract":"This document is illustration of one real sheet metal product, which manufacturing is really challenging and many problems occur in production. In this paper there is given some point of views, which should be take into consideration before the part can be produced without (or some minimal) problems.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"221 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122525909","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942330
Kensuke Tsuchiya, Kentaro Takayama, Wenjun Zhou, T. Hamaguchi, M. Nakao
The authors propose a method for measuring a micro force using a micro manipulator with low rigidity. In order to understand micro scale phenomena and design better micro devices, we have to do much more strength tests or destructive tests on micro objects, such as to apply some force and detect its behavior, response or deflection. We developed a system to move a probe along 3 axes. The tip end of the manipulator could be shaped into a suitable shape for a target. Using the system, we carried out three strength tests of micro objects, such as measuring mechanical properties of nanowire, shear strength of fixed abrasive grains and mechanical strength of chromosomes. Through these demonstrations, we confirmed the validity of our proposal.
{"title":"Measuring mechanical properties of micro structures using micro manipulator with low rigidity","authors":"Kensuke Tsuchiya, Kentaro Takayama, Wenjun Zhou, T. Hamaguchi, M. Nakao","doi":"10.1109/ISAM.2011.5942330","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942330","url":null,"abstract":"The authors propose a method for measuring a micro force using a micro manipulator with low rigidity. In order to understand micro scale phenomena and design better micro devices, we have to do much more strength tests or destructive tests on micro objects, such as to apply some force and detect its behavior, response or deflection. We developed a system to move a probe along 3 axes. The tip end of the manipulator could be shaped into a suitable shape for a target. Using the system, we carried out three strength tests of micro objects, such as measuring mechanical properties of nanowire, shear strength of fixed abrasive grains and mechanical strength of chromosomes. Through these demonstrations, we confirmed the validity of our proposal.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131195723","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942355
Thomas Rollmann, Anselm L. Schule, Oliver Weitzmann, R. Anderl
Feature precedence graphs are well-known models to describe products for process planning purposes. In this paper, we propose a process planning approach for integral sheet metal parts with higher order bifurcations. Those products are produced in a continuous manufacturing process by applying the new manufacturing technologies of linear flow splitting and linear bend splitting in combination with roll forming. We introduce new form-features, operation features, and forming features to represent integral sheet metal parts of higher order bifurcations from a design and manufacturing perspective on different levels of detail. The resulting feature precedence graphs are acyclic directed graphs. Thus, topological sorting algorithms can be applied to generate feasible sequences in the model.
{"title":"Feature precedence graphs as an approach for the forming operations planning of integral sheet metal parts","authors":"Thomas Rollmann, Anselm L. Schule, Oliver Weitzmann, R. Anderl","doi":"10.1109/ISAM.2011.5942355","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942355","url":null,"abstract":"Feature precedence graphs are well-known models to describe products for process planning purposes. In this paper, we propose a process planning approach for integral sheet metal parts with higher order bifurcations. Those products are produced in a continuous manufacturing process by applying the new manufacturing technologies of linear flow splitting and linear bend splitting in combination with roll forming. We introduce new form-features, operation features, and forming features to represent integral sheet metal parts of higher order bifurcations from a design and manufacturing perspective on different levels of detail. The resulting feature precedence graphs are acyclic directed graphs. Thus, topological sorting algorithms can be applied to generate feasible sequences in the model.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131439354","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942367
B. Scholz-Reiter, Thomas Makuschewitz
Long-term production capacity planning has to anticipate future shifts of customer demand. The resulting gap between currently utilized production capacity and available capacity determines the robustness of a production network. In this paper a new approach for assessing the costs of a robust capacity allocation is presented. To this end production networks are modeled by multiclass queueing networks that can be approximated by fluid models. The stability radius reflects the smallest shift of customer demand that destabilizes the network and is used as a measure for robustness. Based on findings for this measure an optimization problem for a cost-oriented capacity allocation is set up.
{"title":"Assessing the cost of robust capacity allocation for serving dynamic customer demand","authors":"B. Scholz-Reiter, Thomas Makuschewitz","doi":"10.1109/ISAM.2011.5942367","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942367","url":null,"abstract":"Long-term production capacity planning has to anticipate future shifts of customer demand. The resulting gap between currently utilized production capacity and available capacity determines the robustness of a production network. In this paper a new approach for assessing the costs of a robust capacity allocation is presented. To this end production networks are modeled by multiclass queueing networks that can be approximated by fluid models. The stability radius reflects the smallest shift of customer demand that destabilizes the network and is used as a measure for robustness. Based on findings for this measure an optimization problem for a cost-oriented capacity allocation is set up.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115930619","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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