Photo-imageable-dielectric (PID) materials and the Micro-filled Via (MfVia) technology are utilized to make the ViperBGA (VBGA), a thermally enhanced BGA package substrate. The thermal performance of the VBGA packages was evaluated by wind tunnel tests of JEDEC standard and FEM simulations. It is shown that the thermal resistance Θja of any given package can be approximated by a rational function of the power level and the airflow speed. One advantage of such expression is that the thermal resistance of the package under any condition can be confidently predicted, and the other is that more reliable numerical predictions can be achieved. This paper also describes how to approach a confident FEM modeling of the wind tunnel tests in terms of heat transfer coefficients and other factors.
{"title":"Thermal Performance Evaluation of VBGA Packages","authors":"Wenjie Zheng, P.Y.F. Wu, James J. D. Lan","doi":"10.1115/imece1997-1107","DOIUrl":"https://doi.org/10.1115/imece1997-1107","url":null,"abstract":"\u0000 Photo-imageable-dielectric (PID) materials and the Micro-filled Via (MfVia) technology are utilized to make the ViperBGA (VBGA), a thermally enhanced BGA package substrate. The thermal performance of the VBGA packages was evaluated by wind tunnel tests of JEDEC standard and FEM simulations. It is shown that the thermal resistance Θja of any given package can be approximated by a rational function of the power level and the airflow speed. One advantage of such expression is that the thermal resistance of the package under any condition can be confidently predicted, and the other is that more reliable numerical predictions can be achieved. This paper also describes how to approach a confident FEM modeling of the wind tunnel tests in terms of heat transfer coefficients and other factors.","PeriodicalId":432053,"journal":{"name":"Manufacturing Science and Engineering: Volume 1","volume":"294 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117354041","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}
Under the lasers in manufacturing curriculum development, a two-course sequence has been initiated into our curriculum. The courses, “Principles of Industrial Lasers,” and “Laser Materials Processing,” integrate theoretical and experimental research results in laser processing of materials with the fundamental characteristics of lasers. Each course constitutes three hours of lectures a week. Associated with each course is a required term project that involves modeling or analysis, computer simulation, and experimental implementation.
{"title":"Multi-Media Developments for a Laser Processing Curriculum","authors":"E. Kannatey-Asibu","doi":"10.1115/imece1997-1123","DOIUrl":"https://doi.org/10.1115/imece1997-1123","url":null,"abstract":"\u0000 Under the lasers in manufacturing curriculum development, a two-course sequence has been initiated into our curriculum. The courses, “Principles of Industrial Lasers,” and “Laser Materials Processing,” integrate theoretical and experimental research results in laser processing of materials with the fundamental characteristics of lasers. Each course constitutes three hours of lectures a week. Associated with each course is a required term project that involves modeling or analysis, computer simulation, and experimental implementation.","PeriodicalId":432053,"journal":{"name":"Manufacturing Science and Engineering: Volume 1","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120945849","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 new approach is presented to estimate the thermal deformation of machine tool, which is generally defined by the relative displacement between the tool and the workpiece. Unlike the conventional approaches based on measurement of the temperature distribution with thermocouples, the new approach is based on measurement of strain distribution, which is considered to give more accurate information about the deformation. A new sensor is developed to measure the true strain including the thermal influence, since it can not be measured by the conventional strain gauge sensors. The developed sensor is applied to estimation of the thermal deformation of a machining center. Fundamental properties of the sensor and the estimated results of thermal deformation are reported.
{"title":"Prediction of Thermal Deformation of Machine Tool With Strain Sensor","authors":"T. Moriwaki, E. Shamoto, M. Kawano","doi":"10.1115/imece1997-1086","DOIUrl":"https://doi.org/10.1115/imece1997-1086","url":null,"abstract":"\u0000 A new approach is presented to estimate the thermal deformation of machine tool, which is generally defined by the relative displacement between the tool and the workpiece. Unlike the conventional approaches based on measurement of the temperature distribution with thermocouples, the new approach is based on measurement of strain distribution, which is considered to give more accurate information about the deformation. A new sensor is developed to measure the true strain including the thermal influence, since it can not be measured by the conventional strain gauge sensors. The developed sensor is applied to estimation of the thermal deformation of a machining center. Fundamental properties of the sensor and the estimated results of thermal deformation are reported.","PeriodicalId":432053,"journal":{"name":"Manufacturing Science and Engineering: Volume 1","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125923877","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 describes the design and implementation of a PC based Open Architecture machine tool controller. The PC based OAC is based on a distributed, peer to peer functional model of the entire machine controller system. Machine motion and I/O functionality is provided by a machine server module. The machine server is designed to provide a uniform interface, and layer of abstraction, for user applications to all machine services. A PC based motion and I/O solution was designed to provide an open, standard interface to the machine. The overall cost / performance ratio of the PC based OAC makes it an attractive alternative to conventional machine tool control technologies. Intelligent process monitoring and control strategies are implemented with the OAC on a 3-axis machining centre. Power, force, and vibration monitoring and control applications are discussed in this paper.
{"title":"PC Based Open Architecture Machine Tool Control","authors":"T. Bailey, D. D. A. Renton, M. A. Elbestawl","doi":"10.1115/imece1997-1073","DOIUrl":"https://doi.org/10.1115/imece1997-1073","url":null,"abstract":"\u0000 This paper describes the design and implementation of a PC based Open Architecture machine tool controller. The PC based OAC is based on a distributed, peer to peer functional model of the entire machine controller system. Machine motion and I/O functionality is provided by a machine server module. The machine server is designed to provide a uniform interface, and layer of abstraction, for user applications to all machine services. A PC based motion and I/O solution was designed to provide an open, standard interface to the machine. The overall cost / performance ratio of the PC based OAC makes it an attractive alternative to conventional machine tool control technologies. Intelligent process monitoring and control strategies are implemented with the OAC on a 3-axis machining centre. Power, force, and vibration monitoring and control applications are discussed in this paper.","PeriodicalId":432053,"journal":{"name":"Manufacturing Science and Engineering: Volume 1","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130551062","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 research is focused on the investigation of robust surface interrogation tools which can support the planning and programming of 5-axis die/mold surface machining. Surface curvature information is evaluated to determine optimal tool orientation for 5-axis machining. A method for calculating machining strip width is proposed for 5-axis cutter path generation. This paper is focused on the development of computational geometry techniques and their application to design, analysis, and manufacturing automation. The proposed planning and programming methodology consists of two steps: 1) machining strip width evaluation, and 2) optimum tool orientation for 5-axis machining. This proposed research can be used to improve the quality of 5-axis die/mold machining.
{"title":"Feasible Machining Strip Evaluation for 5-Axis CNC Die and Mold Machining","authors":"Yuan-Shin Lee, H. Ji","doi":"10.1115/imece1997-1089","DOIUrl":"https://doi.org/10.1115/imece1997-1089","url":null,"abstract":"\u0000 This research is focused on the investigation of robust surface interrogation tools which can support the planning and programming of 5-axis die/mold surface machining. Surface curvature information is evaluated to determine optimal tool orientation for 5-axis machining. A method for calculating machining strip width is proposed for 5-axis cutter path generation. This paper is focused on the development of computational geometry techniques and their application to design, analysis, and manufacturing automation. The proposed planning and programming methodology consists of two steps: 1) machining strip width evaluation, and 2) optimum tool orientation for 5-axis machining. This proposed research can be used to improve the quality of 5-axis die/mold machining.","PeriodicalId":432053,"journal":{"name":"Manufacturing Science and Engineering: Volume 1","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114341832","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}
Within the ESPRIT III project OSACA (Open System Architecture for Controls within Automation systems) of the European Commission the necessary specifications for an open control system were worked out and first prototypes of the system platform were realized. The system platform is the basis of the OSACA architecture and acts as the framework for the integration of application-oriented functionality in a control system. Several initiatives — under them the German project HÜMNOS — are developing application modules for the OSACA architecture. This paper describes the results that have come out of the OSACA initiative so far, and explains the general structure and design of control applications for the provided framework. Special emphasis is put on the reference architecture which guarantees the interoperability between the single control-specific, vendor-neutral application modules. As illustration, the interaction of an HMI application with OSACA compliant controllers of different vendors is presented.
{"title":"Designing Applications for an OSACA Control","authors":"W. Sperling, P. Lutz","doi":"10.1115/imece1997-1080","DOIUrl":"https://doi.org/10.1115/imece1997-1080","url":null,"abstract":"\u0000 Within the ESPRIT III project OSACA (Open System Architecture for Controls within Automation systems) of the European Commission the necessary specifications for an open control system were worked out and first prototypes of the system platform were realized. The system platform is the basis of the OSACA architecture and acts as the framework for the integration of application-oriented functionality in a control system.\u0000 Several initiatives — under them the German project HÜMNOS — are developing application modules for the OSACA architecture. This paper describes the results that have come out of the OSACA initiative so far, and explains the general structure and design of control applications for the provided framework. Special emphasis is put on the reference architecture which guarantees the interoperability between the single control-specific, vendor-neutral application modules. As illustration, the interaction of an HMI application with OSACA compliant controllers of different vendors is presented.","PeriodicalId":432053,"journal":{"name":"Manufacturing Science and Engineering: Volume 1","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134235589","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}
Thermally induced bearing loads have long been recognized as a key factor impacting the reliability and performance of machine tool spindle systems. This is particularly true for reconfigurable machine tool spindles which may experience a wide range of external loads, processes and spindle speeds. Recent research on a roller bearing spindle has shown that it may be possible to control these loads by controlling the temperature distribution within the spindle housing. As this research focused on thermally induced loads in roller bearings, the bearing load model used was largely limited to a radial heat transfer/thermal expansion model. The purpose of this paper is to present a first step model for developing a methodology for designing bearing load monitoring and control systems for reconfigurable angular contact bearing spindles. The proposed model focuses on the thermally and mechanically induced spindle bearing loads in a back to back angular contact bearing pair that are due to radial and axial thermal expansion as well as the centrifugal forces and moments of the bearing balls. Simulation results demonstrate that the proposed model is capable of predicting the interactions between bearing loads and spindle deflections that are likely to be important in the design of future reconfigurable machine tool spindle bearing load monitoring and control systems.
{"title":"A Thermomechanical Model of Machine Tool Spindles for Use in the Design of Reconfigurable Angular Contact Spindle Bearing Load Control Systems","authors":"A. Gibson, J. Stein, J. Tu","doi":"10.1115/imece1997-1071","DOIUrl":"https://doi.org/10.1115/imece1997-1071","url":null,"abstract":"\u0000 Thermally induced bearing loads have long been recognized as a key factor impacting the reliability and performance of machine tool spindle systems. This is particularly true for reconfigurable machine tool spindles which may experience a wide range of external loads, processes and spindle speeds. Recent research on a roller bearing spindle has shown that it may be possible to control these loads by controlling the temperature distribution within the spindle housing. As this research focused on thermally induced loads in roller bearings, the bearing load model used was largely limited to a radial heat transfer/thermal expansion model. The purpose of this paper is to present a first step model for developing a methodology for designing bearing load monitoring and control systems for reconfigurable angular contact bearing spindles. The proposed model focuses on the thermally and mechanically induced spindle bearing loads in a back to back angular contact bearing pair that are due to radial and axial thermal expansion as well as the centrifugal forces and moments of the bearing balls. Simulation results demonstrate that the proposed model is capable of predicting the interactions between bearing loads and spindle deflections that are likely to be important in the design of future reconfigurable machine tool spindle bearing load monitoring and control systems.","PeriodicalId":432053,"journal":{"name":"Manufacturing Science and Engineering: Volume 1","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114320000","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 unified constitutive model for polymer films is proposed with viscoelastic characterization at small deformation and viscoplastic characterization at large deformation, based on molecular chain deformation mechanisms. The evolution equations and the temperature dependence of drag stress and back stress are well established from molecular network theories. The material constants are then determined by master curves and a consistent procedure. The excellent agreement between experimental data of polycarbonate film tests and model predictions is achieved.
{"title":"Constitutive Modeling of Polymer Films From Viscoelasticity to Viscoplasticity","authors":"Z. Qian, Minfu Lu, Sheng Liu","doi":"10.1115/1.2792605","DOIUrl":"https://doi.org/10.1115/1.2792605","url":null,"abstract":"\u0000 A unified constitutive model for polymer films is proposed with viscoelastic characterization at small deformation and viscoplastic characterization at large deformation, based on molecular chain deformation mechanisms. The evolution equations and the temperature dependence of drag stress and back stress are well established from molecular network theories. The material constants are then determined by master curves and a consistent procedure. The excellent agreement between experimental data of polycarbonate film tests and model predictions is achieved.","PeriodicalId":432053,"journal":{"name":"Manufacturing Science and Engineering: Volume 1","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114845572","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}
Quasistatic error sources, which include thermal, mechanical loading and geometric error sources, are responsible for a very large proportion (typically, 70%) of the volumetric errors of a CNC machine tool. This paper discusses the development of a general quasistatic error model for multi-axis CNC machining centers using rigid body kinematics. To predict the quasistatic errors at any position in the workspace, a new method was proposed using the meshing concepts developed in the FEM literature. Finally, the spatial rate of change of the error was analyzed. The model and analysis method can be used as the basis of a compensation scheme as well as in budgeting of errors on a machine tool.
{"title":"Prediction of Quasistatic Errors in Three-Axis CNC Machining Centers","authors":"Xiong Chen, Aseervadam Geddam","doi":"10.1115/imece1997-1075","DOIUrl":"https://doi.org/10.1115/imece1997-1075","url":null,"abstract":"\u0000 Quasistatic error sources, which include thermal, mechanical loading and geometric error sources, are responsible for a very large proportion (typically, 70%) of the volumetric errors of a CNC machine tool. This paper discusses the development of a general quasistatic error model for multi-axis CNC machining centers using rigid body kinematics. To predict the quasistatic errors at any position in the workspace, a new method was proposed using the meshing concepts developed in the FEM literature. Finally, the spatial rate of change of the error was analyzed. The model and analysis method can be used as the basis of a compensation scheme as well as in budgeting of errors on a machine tool.","PeriodicalId":432053,"journal":{"name":"Manufacturing Science and Engineering: Volume 1","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116434848","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}
Modeling texture of milled surfaces using analytic methods requires explicit knowledge of a large number of variables some of which change during machining. These include dynamically changing tool runout, deflection, work-piece material properties, displacement of the workpiece within its fixture and others. Due to the complexity of all factors combined, an alternative approach is presented utilizing the ability of neural networks and fractals to implicitly account for these combined conditions. In the initial model, predicted surface points are first connected using splines to reconstruct 3D surface maps. Results are presented over varying several cutting parameters. Then, replacing splines, an improved fractal method is presented that determines fractal characteristics of milled surfaces to reconstruct more representative surface maps on a small scale. The fractal character of self-similarity within surfaces as manifested by the fractal dimension provides evidence of chaos in milling.
{"title":"Modeling Texture of Peripheral-Milled Surfaces Using a Neural Network and Fractal Method With Evidence of Chaos","authors":"G. Stark, K. Moon","doi":"10.1115/imece1997-1088","DOIUrl":"https://doi.org/10.1115/imece1997-1088","url":null,"abstract":"\u0000 Modeling texture of milled surfaces using analytic methods requires explicit knowledge of a large number of variables some of which change during machining. These include dynamically changing tool runout, deflection, work-piece material properties, displacement of the workpiece within its fixture and others. Due to the complexity of all factors combined, an alternative approach is presented utilizing the ability of neural networks and fractals to implicitly account for these combined conditions. In the initial model, predicted surface points are first connected using splines to reconstruct 3D surface maps. Results are presented over varying several cutting parameters. Then, replacing splines, an improved fractal method is presented that determines fractal characteristics of milled surfaces to reconstruct more representative surface maps on a small scale. The fractal character of self-similarity within surfaces as manifested by the fractal dimension provides evidence of chaos in milling.","PeriodicalId":432053,"journal":{"name":"Manufacturing Science and Engineering: Volume 1","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123415128","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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