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Economic comparison of wire harness assembly systems
1994 abstract index
Simulation is an invaluable tool in designing and analyzing manufacturing systems. A Petri net-based simulation tool is presented to aid simulation projects in manufacturing, including flexible manufacturing systems (FMSs). Three models are developed-an object model, Petri net model, and control model. While hardware components of FMSs are modeled by Petri net objects, control functions are separately modeled and integrated with a Petri net model to resolve conflicts occurring in Petri net execution. Facilities of the developed tool are presented, and a modeling procedure with the tool is illustrated via a case study. Keywords: Petri Nets, Simulation,
Modeling,
Flexible manufacturing and assembly systems consist of machines, robots, and automated guided vehicles aimed at meeting dynamically changing market needs. Numerous asynchronous concurrent actions involved in these systems make analysis of them difficult. Breakdowns of system components further complicate investigation of issues related to design, performance optimization, and control. This paper proposes a new class of modeling tools called augmented timed Petri nets (ATPNS) for modeling and analyzing robotic assembly systems with breakdowns. These models aid designers in better understanding the concurrency, synchronization, and sequential relations involved in breakdown handling and in system simulation for performance analysis. A flexible assembly system consisting of three robots with various breakdown rates is used to illustrate modeling, simulation, and analysis with ATPNs. ATPN models for breakdown handling are presented and analyzed for estimating system performance and for designing the optimum number of assembly fixtures. ATPN models can also be used for real-time system control. Finally, possible extensions to this study are discussed. Keywords: Breakdown Handling, Flexible Assembly Systems, Petri Nets, System Modeling, System Design
FMS
Grouping Parts with a Neural Network, Yunkung and Andrew Kusiak, pp. 262-275
Chung
Recognition of objects is used for identification, classification, verification, and inspection tasks in manufacturing. Neural networks are well suited for this application. In this paper, an application of a back-propagation neural network for the grouping of parts is presented. The back-propagation neural network is provided with binary images describing geometric part shapes, and it generates part families. To decrease the chance of reaching a local optimum and to speed up the computation process, three parameters-bias, momentum, and learning rate-are taken into consideration. The contribution of this paper is in design of a neuro-based system to group parts. The network groups all of the training and testing parts into part families with perfect accuracy. Performance of the system has been tested on a benchmark example and then by experimenting with 60 parts. Keywords: Group Technology, Networks, Artificial Intelligence
Manufacturing,
Volume 13/Number 5 Computer-Aided Process Planning for EDM Operations, Bert Lauwers and Jean-Pierre Kruth, pp. 3 13-322 This paper describes a computer-aided process planning system for electrical discharge machining (EDM). Input to the system is a workpiece description based on process planning features. New process planning feature types have been defined because existing standards such as the CAM-I feature catalog only describe features for prismatic parts. Each feature is characterized by a generic process plan. Generic process plans define possible manufacturing operations that can be applied to a feature. The developed process planning system evaluates the generic process plans of all features included in the workpiece description and combines them into an optimal process plan based on minimal cost. A general strategy to estimate EDM machining times is presented.
Neural
Economic Comparison of Wire Harness Assembly Systems, E. Aguirre and B. Raucent, pp. 276-288 This paper describes typical wire harness assembly methods, including manual. semiautomatic, automatic, and robotized assembly systems. For each case, mathematical models are developed to describe economic performance. The various systems are compared to the harness specification. Finally, the future role of the robotized system is discussed. Keywords: Wire Harness, Assembly Systems, Economic Comparison, Automatic Assembly. Robotic Assembly
Keywords: Computer-Aided Process Planning (CAPP), Electrical Discharge Machining (EDM), Process Planning Features, Knowledge-Based Systems
Augmented Timed Petri Nets for Modeling, Simulation, and Analysis of Robotic Systems with Breakdowns, Kurapati Venkatesh, Mehdi Kaighobadi, MengChu Zhou, and Reggie J. Caudill, pp. 289-301
Planning and Scheduling in Japanese Semiconductor Manufacturing, Izak Duenyas, John W. Fowler. and Lee W. Schruben, pp. 323-332
453
Simulation is an invaluable tool in designing and analyzing manufacturing systems. A Petri net-based simulation tool is presented to aid simulation projects in manufacturing, including flexible manufacturing systems (FMSs). Three models are developed-an object model, Petri net model, and control model. While hardware components of FMSs are modeled by Petri net objects, control functions are separately modeled and integrated with a Petri net model to resolve conflicts occurring in Petri net execution. Facilities of the developed tool are presented, and a modeling procedure with the tool is illustrated via a case study. Keywords: Petri Nets, Simulation,
Modeling,
Flexible manufacturing and assembly systems consist of machines, robots, and automated guided vehicles aimed at meeting dynamically changing market needs. Numerous asynchronous concurrent actions involved in these systems make analysis of them difficult. Breakdowns of system components further complicate investigation of issues related to design, performance optimization, and control. This paper proposes a new class of modeling tools called augmented timed Petri nets (ATPNS) for modeling and analyzing robotic assembly systems with breakdowns. These models aid designers in better understanding the concurrency, synchronization, and sequential relations involved in breakdown handling and in system simulation for performance analysis. A flexible assembly system consisting of three robots with various breakdown rates is used to illustrate modeling, simulation, and analysis with ATPNs. ATPN models for breakdown handling are presented and analyzed for estimating system performance and for designing the optimum number of assembly fixtures. ATPN models can also be used for real-time system control. Finally, possible extensions to this study are discussed. Keywords: Breakdown Handling, Flexible Assembly Systems, Petri Nets, System Modeling, System Design
FMS
Grouping Parts with a Neural Network, Yunkung and Andrew Kusiak, pp. 262-275
Chung
Recognition of objects is used for identification, classification, verification, and inspection tasks in manufacturing. Neural networks are well suited for this application. In this paper, an application of a back-propagation neural network for the grouping of parts is presented. The back-propagation neural network is provided with binary images describing geometric part shapes, and it generates part families. To decrease the chance of reaching a local optimum and to speed up the computation process, three parameters-bias, momentum, and learning rate-are taken into consideration. The contribution of this paper is in design of a neuro-based system to group parts. The network groups all of the training and testing parts into part families with perfect accuracy. Performance of the system has been tested on a benchmark example and then by experimenting with 60 parts. Keywords: Group Technology, Networks, Artificial Intelligence
Manufacturing,
Volume 13/Number 5 Computer-Aided Process Planning for EDM Operations, Bert Lauwers and Jean-Pierre Kruth, pp. 3 13-322 This paper describes a computer-aided process planning system for electrical discharge machining (EDM). Input to the system is a workpiece description based on process planning features. New process planning feature types have been defined because existing standards such as the CAM-I feature catalog only describe features for prismatic parts. Each feature is characterized by a generic process plan. Generic process plans define possible manufacturing operations that can be applied to a feature. The developed process planning system evaluates the generic process plans of all features included in the workpiece description and combines them into an optimal process plan based on minimal cost. A general strategy to estimate EDM machining times is presented.
Neural
Economic Comparison of Wire Harness Assembly Systems, E. Aguirre and B. Raucent, pp. 276-288 This paper describes typical wire harness assembly methods, including manual. semiautomatic, automatic, and robotized assembly systems. For each case, mathematical models are developed to describe economic performance. The various systems are compared to the harness specification. Finally, the future role of the robotized system is discussed. Keywords: Wire Harness, Assembly Systems, Economic Comparison, Automatic Assembly. Robotic Assembly
Keywords: Computer-Aided Process Planning (CAPP), Electrical Discharge Machining (EDM), Process Planning Features, Knowledge-Based Systems
Augmented Timed Petri Nets for Modeling, Simulation, and Analysis of Robotic Systems with Breakdowns, Kurapati Venkatesh, Mehdi Kaighobadi, MengChu Zhou, and Reggie J. Caudill, pp. 289-301
Planning and Scheduling in Japanese Semiconductor Manufacturing, Izak Duenyas, John W. Fowler. and Lee W. Schruben, pp. 323-332
453