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On-line position recognition for autonomous AGV navigational systems
Journal of Manufacturing Systems Volume 12/No. 6
1993 abstract index controller depends on the complexity of the control problem, the number of alternative policies considered, and the methodology to arrive at the best decision, among several others. In this paper, the complexity during the on-line analysis of interruptions caused by machine breakdowns and rush orders in an FMS is discussed. These interruptions affect the manufacturing plan and require changes in the loading and scheduling decisions. Even if the number of machines and part types in an FMS is small, the complexity is extremely high. An integrated decision support system using a knowledge-based on-line simulation (KBOLS) architecture is developed to perform the interruption analysis. Using an emulated FMS, several experiments were conducted to examine the impact of the KBOLS architecture in reducing the complexity problem. The results from these experiments, along with response time studies are reported. Keywords: Interruptions, Machine Breakdown, Rush Order, Knowledge Bases, Blackboard, Response Time, Flexible Manufacturing, Order of Complexity
and standardization, and features and languages. An overview of some academic feature-based design systems is provided. Future research issues in feature-based design are outlined. The conclusion is that feature-based design is still in its infancy and that more research is needed for a better support of the design process and better integration with manufacturing, although major advances have already been made. Keywords: Features, Form Features, Design Features, Manufacturing Features, Design by Features, FeatureBased Design, Feature-Based Process Planning, Multiple Views on Features, Feature Representation, Feature Validation, Tolerances, Standardization, Languages, Intelligent CAD, Object Orientation, Feature Taxonomies, CAD/CAPP Integration, Design Process
Feature Representation and Classification for Automatic Process Planning Systems, T. Kang and B. Nnaji, pp. 133-145 There is no universally accepted definition and representation for object features. However, it is generally agreed that features must have attributes that have to do with the geometry of the part. Features also have attributes that deal with the function they serve in the part. In general, feature representation and classification are domain-specific. In this paper, a generalized feature definition is presented, and schemes for classification and representation of features in the domains of mechanical assembly and sheet metal fabrication are developed and presented. Keywords: Process Planning, CAD, CAM, Automated Machining
Simulation of an Apparel Assembly Cell with Walking Workers and Decouplers, J. Black and B. Schroer, pp. 170-180 In the apparel industry, cells for manufacturing and assembly are called modules. A simulation model has been developed to study the behavior of a unique module that employed five multifunctional, walking workers and 13 sewing stations with great variations in processing times. Cells are the major components in integrated pull manufacturing systems (IPMSs). IPMSs are the designs for the factories with a future. Keywords: Manufacturing and Assembly Cells, Pull Control, Apparel, Decouplers
On-Line Position Recognition for Autonomous AGV Novigational Systems, Z. Katz and J. Asbury, pp. 146-152 The accuracy of an autonomous AGV in following a predetermined path is highly dependent on its navigational capability. Position recognition requires integrating communication, mapping, guidance, and navigation. The hardware and software development for such a system is presented. Aspects of the system's interaction are discussed, and specific design attributes are evaluated and highlighted. Keywords: Automated Guided Vehicles, Navigation, Sensors, Manufacturing
A Real-Time Computer-Aided Process Planning System as a Support Tool for Economic Product Design, J. Park and B. Khoshnevis, pp. 181-193 A new computer-aided process planning (CAPP) system is presented that serves as a tool for concurrent design of prismatic parts and their manufacturing processes. The system provides timely manufacturing cost feedback to the designer for each added design feature. A hierarchical planning technique, an expert system with a multibank rule base, and a dynamic programming-based optimization module are employed in this real-time process planning system. Keywords: Automated Process Planning, Computer-Aided Design, Concurrent Engineering, Expert Systems, Dynamic Programming, Value Analysis, Design Cost Evaluation
Complexity Reduction During Interruption Analysis in a Flexible Manufacturing System Using Knowledge-Based On-Line Simulation, P. Tayanithi, S. Manivannan, and J. Banks, pp. 153-169 One of the major challenges for a supervisory controller in a flexible manufacturing system (FMS) is to react quickly to a problem and provide decisions in the shortest possible time using the most accurate and reliable information obtained from the shop floor. The response time of the
Volume 12/Number 3 Thailand's Manufacturing Sector: Issues on Development, Technology, and Management, M. Tabucanon, pp. 199-203
515
1993 abstract index controller depends on the complexity of the control problem, the number of alternative policies considered, and the methodology to arrive at the best decision, among several others. In this paper, the complexity during the on-line analysis of interruptions caused by machine breakdowns and rush orders in an FMS is discussed. These interruptions affect the manufacturing plan and require changes in the loading and scheduling decisions. Even if the number of machines and part types in an FMS is small, the complexity is extremely high. An integrated decision support system using a knowledge-based on-line simulation (KBOLS) architecture is developed to perform the interruption analysis. Using an emulated FMS, several experiments were conducted to examine the impact of the KBOLS architecture in reducing the complexity problem. The results from these experiments, along with response time studies are reported. Keywords: Interruptions, Machine Breakdown, Rush Order, Knowledge Bases, Blackboard, Response Time, Flexible Manufacturing, Order of Complexity
and standardization, and features and languages. An overview of some academic feature-based design systems is provided. Future research issues in feature-based design are outlined. The conclusion is that feature-based design is still in its infancy and that more research is needed for a better support of the design process and better integration with manufacturing, although major advances have already been made. Keywords: Features, Form Features, Design Features, Manufacturing Features, Design by Features, FeatureBased Design, Feature-Based Process Planning, Multiple Views on Features, Feature Representation, Feature Validation, Tolerances, Standardization, Languages, Intelligent CAD, Object Orientation, Feature Taxonomies, CAD/CAPP Integration, Design Process
Feature Representation and Classification for Automatic Process Planning Systems, T. Kang and B. Nnaji, pp. 133-145 There is no universally accepted definition and representation for object features. However, it is generally agreed that features must have attributes that have to do with the geometry of the part. Features also have attributes that deal with the function they serve in the part. In general, feature representation and classification are domain-specific. In this paper, a generalized feature definition is presented, and schemes for classification and representation of features in the domains of mechanical assembly and sheet metal fabrication are developed and presented. Keywords: Process Planning, CAD, CAM, Automated Machining
Simulation of an Apparel Assembly Cell with Walking Workers and Decouplers, J. Black and B. Schroer, pp. 170-180 In the apparel industry, cells for manufacturing and assembly are called modules. A simulation model has been developed to study the behavior of a unique module that employed five multifunctional, walking workers and 13 sewing stations with great variations in processing times. Cells are the major components in integrated pull manufacturing systems (IPMSs). IPMSs are the designs for the factories with a future. Keywords: Manufacturing and Assembly Cells, Pull Control, Apparel, Decouplers
On-Line Position Recognition for Autonomous AGV Novigational Systems, Z. Katz and J. Asbury, pp. 146-152 The accuracy of an autonomous AGV in following a predetermined path is highly dependent on its navigational capability. Position recognition requires integrating communication, mapping, guidance, and navigation. The hardware and software development for such a system is presented. Aspects of the system's interaction are discussed, and specific design attributes are evaluated and highlighted. Keywords: Automated Guided Vehicles, Navigation, Sensors, Manufacturing
A Real-Time Computer-Aided Process Planning System as a Support Tool for Economic Product Design, J. Park and B. Khoshnevis, pp. 181-193 A new computer-aided process planning (CAPP) system is presented that serves as a tool for concurrent design of prismatic parts and their manufacturing processes. The system provides timely manufacturing cost feedback to the designer for each added design feature. A hierarchical planning technique, an expert system with a multibank rule base, and a dynamic programming-based optimization module are employed in this real-time process planning system. Keywords: Automated Process Planning, Computer-Aided Design, Concurrent Engineering, Expert Systems, Dynamic Programming, Value Analysis, Design Cost Evaluation
Complexity Reduction During Interruption Analysis in a Flexible Manufacturing System Using Knowledge-Based On-Line Simulation, P. Tayanithi, S. Manivannan, and J. Banks, pp. 153-169 One of the major challenges for a supervisory controller in a flexible manufacturing system (FMS) is to react quickly to a problem and provide decisions in the shortest possible time using the most accurate and reliable information obtained from the shop floor. The response time of the
Volume 12/Number 3 Thailand's Manufacturing Sector: Issues on Development, Technology, and Management, M. Tabucanon, pp. 199-203
515