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An approach for allocating manufacturing resources to production tasks
Jo-rnaivolume~2~a~.lufaCturing Systems
Cumulative Abstract Index
An Approach for Allocating Mamtfacturing Resources to Production Tasks, G. Chryssolourls, J. Pierce, K. Dickn, pp.
and dynamic characteristics as well as transient and steady state features can be extracted from seven complimentary characterization tests. Subsequent implementation of the procedure with five selected state-of-the-art CIqC mac.'bin/n~ centers in its category reve.~ls. that such machines can deteriorate substantially even in an iaeal environment. This demonstrates the necessity for characterization on a regular basis to assess the performance of new and existing machines. Keywords: CNC ~ h i n i n ~ Centers, Tests Performance
368-82 This paper presents the concept of manufacturing decision making (MADEMA)---a multicriterin decision-making prooedure for manufacturing systems. The concept is besed on a hierarchical structure of the manufacturing system and calls for the execution of four consecutive steps to make decisions on the ent of manufacturing resources to production tasks. utilizes decision theory in tandem with randomized search methods and has been experimentally implemented on a software system written in lisp. Particular emphasis is given to its flexibility in terms of the decision-making criteria used and the tradeoff between system pefformauce and computational effort. This flexibility perm/ts adjustment of the procedure to suit the available computational anviromnant and the required decision making time. This paper includes preliminary simulation results of applying MADEMA to a real life menufncturing workcenter. Keyword~: Decision Making, Manufactoring Systems, Assignment, Manufncturing Resources, Production Tasks, Artificial Intelligence, Operations Research, Flexibility
A Study of Performance Objectives in the 5choduling of Man~acmring L/nes, H. Gumani, P. Johri, pp. 422-29 This paper studies and tries to qmmfify the relationship between several traditional and new scheduling objectives. The considered objectives minimize the makespan, average flowtime, production cycle time, and workload imbalances. All these objectives impro.ve manufacturing efficiency in slightly differentways. The mare focus of this study is to see how these objectives are related to each other. The study is done using a model known as a flow line and is carried out for a large range of system configurations, Processing times of jobs on machines are randomly generated and the various performance objectives are evaluated for I000 randomly generated sequences. Correlations between the different objectives are obtained and scatter plots are generated. Except for makespen and cycle time, the different performance measures considered in this study show surprisingly tittle relationship to each other. Moreover, this relationship varies significantly with problem size and parameter values as well as the initial conditions assumed in the model. Keywords: Scheduling, Sequencing, Makespan, Piowtime, Load Imbalance, Cycle Time, Correlation
A Part Image Reconstruction Systemfor Reverse Engineering of Design Modifications, S. Motavalli, B. Bidenda, pp. 383-95 When the CAD model of an existing part is not available, the reverse engineering involved in the creation of such a model is typically time consuming, tedious, and potentially a source of error. Currently, geometric measurements from the surface of a prototype are extracted manually or through a coordinate meesurg machine end input to a CAD system. This paper outlines a methodology, for the development of part image recons~uction systems (pmrs). The system developed by the authors is microcomputer-basod and uses a noncontnct technique to extract 3-D data from the surface of parts. Algorithms for data acquisition are discussed. Procedures for processing the data into a polygon mesh representation and orthographic projections are detailed. Sample results are also explained. KeywordJ: Reverse Engineering, Rapid Prototyping, Structured Ligh~g, CAD, CAM
1991~ Voi. 10/No. 6 Manufacturing Cost Estimation: A Multivariate Learning Curve AP~ni.roach,A. Badiru, pp. 431-41 s paper introduces an anaiytic framework for extending uuivariate learning curves (manufacturing progress functions) to multivariate models. Multivariate functions are needed to account for the multitude of factors that can influence learning in manufacturing operations. A specific example of a bivariate manufacturing progress function is presented. Keywords: LemmingCurve, Manufacturing Progress Pun,'on, Multivariate Analysis, Cost Estimati~, Productivity Analysis
Automatic Trajectory Planning System (ATPS)for Spray Painting Robots, S. Suh, I. Woo, S. Noh, pp. 396-406
In this paper, we develop an automatic trajectory planning system (ATPS) for~painting robots by a new scheme. This system considers geometric modeling, painting, mechanics, and robot dynamics to output an optimal trajectory (in the sense of coating uniformity and painting time) based on the CAD dam describing the shape of objects. The new scheme is implemented on a SUN/ 4 workstation to develop an ATPS for pamfing robots. To test effectiveness and illustrate the developed system, numerous experiments are performed and analyzed. The practical application of the developed system is to plan an optimal robot trajectory that results in uniform coating thickness in minimum i~aintingtime. Keywords: Trajectory Planning, Off-Line Prognumnmg, Robot Motion, CAD/CAM, Simulation
Application of SimilarityCoe,O~cientMethod to Parts Coding and Classq~cationAnalysisin Group Technology,O. ~ pp. 442-48 This paper presents an alternativemethod of group formation in group technology using partscoding and classification.The majority of machine-part grouping problems use the production flow analysis (PFA) concept in which a machine is assigned a nondcscriptive wesght of 1 if a part ss muted through it, or 0 otherwise. Clusters of machines are then formed using an appropriate similarity coefficient and a grouping algorithm. We introduce this concept to coding and classification where component parts are described and weighted by numerical codes. A grouping algorithm is then used to form groups of the most similar parts to tmnlmlze production and design setup times and costs. A numerical example of the procedure is also presented. Keywords: Group Technology, Coding, Classification
Characterization of CNC Machining Centers, Y. Shin, H. Chin, M. Brink, pp. 407-21 Characterization of CNC machining centers is a difficult task due to its inherent complexity and diversity. Although many different approaches have been proposed, none singularly serves as a globally accepted test procedure. This paper addresses this important issue by establishing a comprehensive characterization procedure for CNC macblnlng centers. It is illustrated that static
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Cumulative Abstract Index
An Approach for Allocating Mamtfacturing Resources to Production Tasks, G. Chryssolourls, J. Pierce, K. Dickn, pp.
and dynamic characteristics as well as transient and steady state features can be extracted from seven complimentary characterization tests. Subsequent implementation of the procedure with five selected state-of-the-art CIqC mac.'bin/n~ centers in its category reve.~ls. that such machines can deteriorate substantially even in an iaeal environment. This demonstrates the necessity for characterization on a regular basis to assess the performance of new and existing machines. Keywords: CNC ~ h i n i n ~ Centers, Tests Performance
368-82 This paper presents the concept of manufacturing decision making (MADEMA)---a multicriterin decision-making prooedure for manufacturing systems. The concept is besed on a hierarchical structure of the manufacturing system and calls for the execution of four consecutive steps to make decisions on the ent of manufacturing resources to production tasks. utilizes decision theory in tandem with randomized search methods and has been experimentally implemented on a software system written in lisp. Particular emphasis is given to its flexibility in terms of the decision-making criteria used and the tradeoff between system pefformauce and computational effort. This flexibility perm/ts adjustment of the procedure to suit the available computational anviromnant and the required decision making time. This paper includes preliminary simulation results of applying MADEMA to a real life menufncturing workcenter. Keyword~: Decision Making, Manufactoring Systems, Assignment, Manufncturing Resources, Production Tasks, Artificial Intelligence, Operations Research, Flexibility
A Study of Performance Objectives in the 5choduling of Man~acmring L/nes, H. Gumani, P. Johri, pp. 422-29 This paper studies and tries to qmmfify the relationship between several traditional and new scheduling objectives. The considered objectives minimize the makespan, average flowtime, production cycle time, and workload imbalances. All these objectives impro.ve manufacturing efficiency in slightly differentways. The mare focus of this study is to see how these objectives are related to each other. The study is done using a model known as a flow line and is carried out for a large range of system configurations, Processing times of jobs on machines are randomly generated and the various performance objectives are evaluated for I000 randomly generated sequences. Correlations between the different objectives are obtained and scatter plots are generated. Except for makespen and cycle time, the different performance measures considered in this study show surprisingly tittle relationship to each other. Moreover, this relationship varies significantly with problem size and parameter values as well as the initial conditions assumed in the model. Keywords: Scheduling, Sequencing, Makespan, Piowtime, Load Imbalance, Cycle Time, Correlation
A Part Image Reconstruction Systemfor Reverse Engineering of Design Modifications, S. Motavalli, B. Bidenda, pp. 383-95 When the CAD model of an existing part is not available, the reverse engineering involved in the creation of such a model is typically time consuming, tedious, and potentially a source of error. Currently, geometric measurements from the surface of a prototype are extracted manually or through a coordinate meesurg machine end input to a CAD system. This paper outlines a methodology, for the development of part image recons~uction systems (pmrs). The system developed by the authors is microcomputer-basod and uses a noncontnct technique to extract 3-D data from the surface of parts. Algorithms for data acquisition are discussed. Procedures for processing the data into a polygon mesh representation and orthographic projections are detailed. Sample results are also explained. KeywordJ: Reverse Engineering, Rapid Prototyping, Structured Ligh~g, CAD, CAM
1991~ Voi. 10/No. 6 Manufacturing Cost Estimation: A Multivariate Learning Curve AP~ni.roach,A. Badiru, pp. 431-41 s paper introduces an anaiytic framework for extending uuivariate learning curves (manufacturing progress functions) to multivariate models. Multivariate functions are needed to account for the multitude of factors that can influence learning in manufacturing operations. A specific example of a bivariate manufacturing progress function is presented. Keywords: LemmingCurve, Manufacturing Progress Pun,'on, Multivariate Analysis, Cost Estimati~, Productivity Analysis
Automatic Trajectory Planning System (ATPS)for Spray Painting Robots, S. Suh, I. Woo, S. Noh, pp. 396-406
In this paper, we develop an automatic trajectory planning system (ATPS) for~painting robots by a new scheme. This system considers geometric modeling, painting, mechanics, and robot dynamics to output an optimal trajectory (in the sense of coating uniformity and painting time) based on the CAD dam describing the shape of objects. The new scheme is implemented on a SUN/ 4 workstation to develop an ATPS for pamfing robots. To test effectiveness and illustrate the developed system, numerous experiments are performed and analyzed. The practical application of the developed system is to plan an optimal robot trajectory that results in uniform coating thickness in minimum i~aintingtime. Keywords: Trajectory Planning, Off-Line Prognumnmg, Robot Motion, CAD/CAM, Simulation
Application of SimilarityCoe,O~cientMethod to Parts Coding and Classq~cationAnalysisin Group Technology,O. ~ pp. 442-48 This paper presents an alternativemethod of group formation in group technology using partscoding and classification.The majority of machine-part grouping problems use the production flow analysis (PFA) concept in which a machine is assigned a nondcscriptive wesght of 1 if a part ss muted through it, or 0 otherwise. Clusters of machines are then formed using an appropriate similarity coefficient and a grouping algorithm. We introduce this concept to coding and classification where component parts are described and weighted by numerical codes. A grouping algorithm is then used to form groups of the most similar parts to tmnlmlze production and design setup times and costs. A numerical example of the procedure is also presented. Keywords: Group Technology, Coding, Classification
Characterization of CNC Machining Centers, Y. Shin, H. Chin, M. Brink, pp. 407-21 Characterization of CNC machining centers is a difficult task due to its inherent complexity and diversity. Although many different approaches have been proposed, none singularly serves as a globally accepted test procedure. This paper addresses this important issue by establishing a comprehensive characterization procedure for CNC macblnlng centers. It is illustrated that static
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