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A hybrid model for analysis of 3-D machining operations
Journal of Manufacturing Systems Vol. 23/No. 4 2004
2003-2004 abstract and ke word index Impact of Bar Code Print Quality on the Performance of High-Speed Sortation Systems, Richard E. Billo, J. David Porter, Mainak Mazumdar, Stephen J. Brown, v22, n4, 2003, pp317-326 This study analyzed the effect of low-quality bar code symbols on the automated high-speed sortation process typically used in large warehouses of high-volume manufacturing and distribution companies. The results were then used to generate recommendations that could be followed to increase the reliability of reading the symbol on the first attempt. Upon printing, the quality of bar code symbols was deliberately varied, then subjected to a physical simulation of the automated sortation process. Independent variables included Symbol Contrast, X Dimension, Bar Growth, Aspect Ratio, Symbol Orientation, Quiet Zones, and Conveyor Line Speed. The dependent variable was the bar code symbol's read rate. Results showed that the bar code symbol read rate was significantly affected by such print quality factors as X Dimension, Bar Growth, and Symbol Contrast. As part of the study, a predictive model was developed that accurately predicts the likelihood of a symbol's read rate upon its printing. Keywords: Automated Sortation, Bar Codes, Distribution, Material Handling, Parcel Shipping, Print Quality
On-Machine Inspection System Accuracy Improvement Using an Artifact, Kyung-Don Kim, Sung-Chong Chung, v22, n4, 2003, pp299-308 A correction methodology of measurement data is proposed for accuracy improvement of an on-machine measurement system. A volumetric error model to synthesize transient thermal and geometric errors is developed. Geometric errors are determined by an off-line calibration procedure. Under the assumption that the on-machine measuring procedure is a pure cooling process, the transient thermal errors are modeled as exponential functions with different thermal time constants and gains. The thermal time constants characterize transient thermal responses of machine elements during the on-machine measurement. The gains are determined by measuring a 3-D artifact twice when the on-machine measurement of a machined part is required. Total time taken for measuring the artifact is less than 5 minutes. Experiments are performed to verify the proposed method. The measuring accuracy of the on-machine inspection system has been improved from 60 pan to 10 jam. Keywords: Accuracy, Artifact, Calibration, Geometric Error, On-Machine Measurement, Thermal Gain, Thermal Time Constant, Transient Thermal Error
A Hybrid ModelforAnalysis of 3-D Machining Operations, Amir H. Adibi-Sedeh, Vis Madhavan, v22, n4, 2003,
Development of a n Automatic Design and Optimization Systemforlndustrial Silencers, Lee Ming Wong, G. Gary Wang, v22, n4, 2003, pp327-339 Current computer-aided design (CAD) software tools focus on rapid production of computer models, which usually takes place after the product design is completed. The product design process, which has more significant influence on product life-cycle costs, is not fully supported. This work documents the development of an automatic design and optimization system for industrial silencers. The developed system shortens the silencer design time from one day to a few minutes, and reduces the production costs by an average of more than 40%. Moreover, the system proves the feasibility of developing an open-architecture CAD system supported by design of experiment (DOE) based optimization methods to integrate product life-cycle considerations into the design. It is expected that the developed system can help the development of similar systems for other products. Through the development of this system, some further research issues are identified. Keywords: Design Automation, DOE, CAD, Design Optimization, Parametric Design, Silencer
pp309-316 This paper describes the development of a physically based model for the analysis of commonly encountered 3D machining processes using arbitrarily oriented cutting tools. This model consists of two modules, a generalized upper bound analysis module capable of handling any given cutting edge geometry, and a 2-D machining analysis module capable of using a wide range of constitutive equations to handle most commonly machined materials. The upper bound module is used for prediction of the chip flow angle and is followed by the application of the extended Oxley's analysis of machining (Adibi-Sedeh, Madhavan, and Bahr 2003a) in the equivalent plane to obtain two components of the cutting force in the plane. The out-of-plane component is calculated by applying the constraint that the resultant cutting force should not have any component along the rake face in a direction perpendicular to the chip flow direction. The performance of the hybrid model is validated through extensive comparison with experimental data for different operations and materials. Keywords: 3-D Machining Processes, Chip Flow Angle, Cutting Forces, Drilling
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2003-2004 abstract and ke word index Impact of Bar Code Print Quality on the Performance of High-Speed Sortation Systems, Richard E. Billo, J. David Porter, Mainak Mazumdar, Stephen J. Brown, v22, n4, 2003, pp317-326 This study analyzed the effect of low-quality bar code symbols on the automated high-speed sortation process typically used in large warehouses of high-volume manufacturing and distribution companies. The results were then used to generate recommendations that could be followed to increase the reliability of reading the symbol on the first attempt. Upon printing, the quality of bar code symbols was deliberately varied, then subjected to a physical simulation of the automated sortation process. Independent variables included Symbol Contrast, X Dimension, Bar Growth, Aspect Ratio, Symbol Orientation, Quiet Zones, and Conveyor Line Speed. The dependent variable was the bar code symbol's read rate. Results showed that the bar code symbol read rate was significantly affected by such print quality factors as X Dimension, Bar Growth, and Symbol Contrast. As part of the study, a predictive model was developed that accurately predicts the likelihood of a symbol's read rate upon its printing. Keywords: Automated Sortation, Bar Codes, Distribution, Material Handling, Parcel Shipping, Print Quality
On-Machine Inspection System Accuracy Improvement Using an Artifact, Kyung-Don Kim, Sung-Chong Chung, v22, n4, 2003, pp299-308 A correction methodology of measurement data is proposed for accuracy improvement of an on-machine measurement system. A volumetric error model to synthesize transient thermal and geometric errors is developed. Geometric errors are determined by an off-line calibration procedure. Under the assumption that the on-machine measuring procedure is a pure cooling process, the transient thermal errors are modeled as exponential functions with different thermal time constants and gains. The thermal time constants characterize transient thermal responses of machine elements during the on-machine measurement. The gains are determined by measuring a 3-D artifact twice when the on-machine measurement of a machined part is required. Total time taken for measuring the artifact is less than 5 minutes. Experiments are performed to verify the proposed method. The measuring accuracy of the on-machine inspection system has been improved from 60 pan to 10 jam. Keywords: Accuracy, Artifact, Calibration, Geometric Error, On-Machine Measurement, Thermal Gain, Thermal Time Constant, Transient Thermal Error
A Hybrid ModelforAnalysis of 3-D Machining Operations, Amir H. Adibi-Sedeh, Vis Madhavan, v22, n4, 2003,
Development of a n Automatic Design and Optimization Systemforlndustrial Silencers, Lee Ming Wong, G. Gary Wang, v22, n4, 2003, pp327-339 Current computer-aided design (CAD) software tools focus on rapid production of computer models, which usually takes place after the product design is completed. The product design process, which has more significant influence on product life-cycle costs, is not fully supported. This work documents the development of an automatic design and optimization system for industrial silencers. The developed system shortens the silencer design time from one day to a few minutes, and reduces the production costs by an average of more than 40%. Moreover, the system proves the feasibility of developing an open-architecture CAD system supported by design of experiment (DOE) based optimization methods to integrate product life-cycle considerations into the design. It is expected that the developed system can help the development of similar systems for other products. Through the development of this system, some further research issues are identified. Keywords: Design Automation, DOE, CAD, Design Optimization, Parametric Design, Silencer
pp309-316 This paper describes the development of a physically based model for the analysis of commonly encountered 3D machining processes using arbitrarily oriented cutting tools. This model consists of two modules, a generalized upper bound analysis module capable of handling any given cutting edge geometry, and a 2-D machining analysis module capable of using a wide range of constitutive equations to handle most commonly machined materials. The upper bound module is used for prediction of the chip flow angle and is followed by the application of the extended Oxley's analysis of machining (Adibi-Sedeh, Madhavan, and Bahr 2003a) in the equivalent plane to obtain two components of the cutting force in the plane. The out-of-plane component is calculated by applying the constraint that the resultant cutting force should not have any component along the rake face in a direction perpendicular to the chip flow direction. The performance of the hybrid model is validated through extensive comparison with experimental data for different operations and materials. Keywords: 3-D Machining Processes, Chip Flow Angle, Cutting Forces, Drilling
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