Optimal configuration selection for Reconfigurable Manufacturing Systems

The selection of Reconfigurable Manufacturing Systems (RMS) configurations that include arrangement of machines, equipment selection, and assignment of operations, has a significant impact on their performance. This paper reviews the relevant literature and highlights the gaps that exist in this area of research. A novel “RMS Configuration Selection Approach” is introduced. It consists of two phases; the first deals with the selection of the near-optimal alternative configurations for each possible demand scenario over the considered configuration periods. It uses a constraint satisfaction procedure and powerful meta-heuristics, real-coded Genetic Algorithms (GAs) and Tabu Search (TS), for the continuous optimization of capital cost and system availability. The second phase utilizes integer-coded GAs and TS to determine the alternatives, from those produced in the first phase, that would optimize the degree of transition smoothness over the planning horizon. It uses a stochastic model of the level of reconfiguration smoothness (RS) across all the configuration periods in the planning horizon according to the anticipated demand scenarios. This model is based on a RS metric and a reconfiguration planning procedure that guide the development of execution plans for reconfiguration. The developed approach is demonstrated and validated using a case study. It was shown that it is possible to provide the manufacturing capacity and functionality needed when needed while minimizing the reconfiguration effort. The proposed approach can provide decision support for management in selecting RMS configurations at the beginning of each configuration period.

A multicriteria intuitionistic fuzzy group decision making for plant location selection with ELECTRE method

Plant location selection, the process of finding a suitable location for plant of a project has a strong influence on the success of industrial venture with the goal to minimize cost and maximize the use of resources. Thus, plant location selection problem is a multicriteria decision-making problem involving several conflicting criteria on which decision makers' knowledge is vague and imprecise. Therefore, in this study, the elimination and choice translating reality (ELECTRE) method is proposed with intuitionistic fuzzy sets for selection of appropriate plant location in group decision-making environment to tackle uncertainty of the information provided by decision makers and a plant location selection problem is considered to illustrate the proposed intuitionistic fuzzy-ELECTRE method. The ratings of alternatives with respect to each criterion and the weights of each criterion are taken as linguistic terms further characterized by triangular intuitionistic fuzzy sets.     

Multi-criteria decision making techniques for compliant polishing tool selection

The International Journal of Advanced Manufacturing Technology - Precision devices require surface finish of a few nanometers. The choice of compliant coated abrasive tools used in manufacturing...     

Development of a machine tool selection system using AHP

The selection of appropriate machines is one of the most critical decisions in the design and development of an efficient production environment. In this study, we propose a decision support system for machine tool selection using an effective algorithm, the analytic hierarchy process. In the selection process, we first consider qualitative decision criteria that are related to the machine properties. Reliability and precision analyses may be included in the detailed evaluation procedure. Furthermore, the decision-maker may take into account the economical considerations through cost analysis. In addition, the robustness of the selection procedure may be evaluated using sensitivity analysis. An illustrative example of machine tool selection using the proposed methodology and the software implementation are provided.     

A visual interactive multicriteria decision analysis model for FMS design

The main goal of this work is to develop a multicriteria decision model aimed at the evaluation of FMS competing design alternatives. The model was developed to support the design team in exploring the strengths and weaknesses of each alternative, to assist the setting of priorities between conflicting manufacturing strategy components (such as flexibility and quality), to study the sensitivity of the behaviour of alternatives to changes in underlying decision situations, and finally to identify a preferred course of action. In summary, the model can be considered as a mechanism for taking into account designer's preferences and wishes, in order to customise the manufacturing system for the user's particular situation. To be effective, the computational implementation of the multicriteria FMS design model provides extensive graphical and interactive facilities both to model structuring and evaluation. Moreover, the model provides animation facilities for visual interactive sensitivity analysis. A case study illustrates the effectiveness of the decision model.     

Double-spiral tool path in configuration space

Using a spiral tool path is a common strategy in many NC machining applications. It can be used for high-speed machining of pockets or as a space-filling curve for finish applications. When using spirals for finishing application, a double spiral is desired to avoid having a starting or end-point at the center of the workpiece. In this paper, we present an algorithm to create a double spiral from offset curves in a precomputed configuration space (c-space). CAD/CAM systems that operate on NURBS surfaces or on triangular meshes have to deal with the issues of patch-boundary oscillations or long, stretched triangles, respectively. This can be avoided when operating in c-space. The c-space is given in the form of a regular quadrilateral heightfield mesh, which may be adaptively subdivided, where the slope is large. This simple data structure is memory efficient and has proven to be beneficial in CAD/CAM frameworks. Our algorithm creates a double spiral by blending adjacent offset curves. The center of the spiral is filled by a b-spline curve. When given offset curves split into multiple components, the algorithm creates multiple smaller spirals and connects them appropriately. The resulting tool path is one large intersection-free curve with starting and end-point on the boundary of the workpiece.     

机床设备选择模型建立及综合评价

应用模糊综合评价理论建立数学模型来评价数控机床,使这种评价科学,实用。     

An analytic network process-based multicriteria decision making model for a reverse supply chain

Reverse logistics has emerged as an important dimension for organizations to build their strategic advantage. Part of this effort relies on potentially outsourcing these activities. With this competitive issue in mind, this paper presents a multistep process to select a third-party reverse logistic provider (3PRLP). Criteria for evaluation are drawn from the literature and practical input from experts and decision makers within a case company. The process requires that an initial screening of criteria is completed through the analytical hierarchy process. The second stage of the process, 3PRLP selection, is completed using the analytic network process. An illustrative example is provided to demonstrate the solutions obtained by the proposed process within an automobile case company. A sensitivity analysis is also provided for a robustness check. The results obtained from the proposed model provide some interesting managerial implications to the case company and others wishing to apply the process.     

面向任务的多指机械手抓取构形评价与优选

基于机械手抓取物体时手指与物体之间构成有摩擦的固定点接触，提出一种面向任务的机械手抓取构形评价方法，在保证一定抓取稳定性和满足任务要求的前提下，以整个操作过程中手指接触力的最大值最小为目标确定最佳的抓取构形。结合实例说明了抓取构形评价与优选方法的应用。     

硬态切削刀具的性能及选用

介绍了硬态切削的优点和PCBN刀具材料的优良性能.合理地选择PCBN刀具的几何参数和切削用量,以提高加工质量.     

AI-based decision support tool for strategic decision making in the factory of the future

The process of strategic decision making is highly complex. Top executives make decisions based on uncertain information, much of which is difficult to quantify, often using intuitive feelings and experience as guiding factors. The demands placed upon high-level managers will increase in the factory of the future, as organizations become less hierarchical, cycle times decrease and customized production becomes a reality. Advances in process technologu will provide high levels of flexibility but knowledge technology, allied to strong and purposeful leadership, will provide the key to competitive success in many industries in future. This paper describes a prototype decision support system and learning tool which uses qualitative frame-based knowledge representation to encapsulate the intuitive knowledge of high-level decision makers. The system allows a user to construct a ‘mind set’ of a particular strategic problem domain, using qualitative relationships to describe the causal effects and interactions between concepts. The resulting knowledge base may then be used for experimentation by altering individual relationships and observing the effects of the change in the structure of the knowledge base.     

机构选型决策模型

针对机构选型设计的多样性和复杂性，建立了选优决策的未确知测度模型。在未确知测度空间的基础上。根据评价空间的有序性，建立评分准则，并对机构选型优劣排序。     

Dry machining of aluminum for proper selection of cutting tool: tool performance and tool wear

Machining of aluminum and its alloy is very difficult due to the adhesion and diffusion of aluminum, thus the formation of built-up edge (BUE) on the surface. The BUE, which affects the surface integrity and tool life significantly, affects the service and performance of the workpiece. The minimization of BUE was carried out by selection of proper cutting speed, feed, depth of cut, and cutting tool material. This paper presents machining of rolled aluminum at cutting speeds of 336, 426, and 540 m/min, the feeds of 0.045, 0.06, and 0.09 mm/rev, and a constant depth of cut of 0.2 mm in dry condition. Five cutting tools WC SPUN grade, WC SPGN grade, WC + PVD (physical vapor deposition) TiN coating, WC + Ti (C, N) + Al₂O₃ PVD multilayer coatings, and PCD (polycrystalline diamond) were utilized for the experiments. The surface roughness produced, total flank wear, and cut chip thicknesses were measured. The characterization of the tool was carried out by a scanning electron microscope (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) pattern. The chip underface was analyzed for the study of chip deformation produced after machining. The results indicated that the PCD tool provides better results in terms of roughness, tool wear, and smoother chip underface. It provides promising results in all aspects.     

A fitness-based weighting mechanism for multicriteria flowshop scheduling using genetic algorithms

The most effective approximate methods to tackle the problem of scheduling jobs in a permutation flowshop with the bicriteria of makespan and maximum tardiness are based on genetic algorithms (GA). In these methods, the performance of the GA is improved by applying local search to all offsprings belonging to the current population. To do so, the two objectives must be aggregated into a single objective, which is usually accomplished by weighting them into a scalar function. Since the weighting scheme is considered to be critical for the performance of the algorithm, several weighting mechanisms have been suggested in the literature. In this paper, we propose two new weighting schemes and conduct an extensive computational experience under a variety of parameter settings in order to show their effectiveness as compared to existing ones.     

机床的总体配置和结构设计(上)

首先从提高机床性能、重视生态环境和关注全生命周期的视角探讨未来机床设计的新方法和机床的结构配置.然后介绍了机床结构优化的基本方法和不同机床结构材料的特点,并从机床结构的质量、刚度和阻尼三者的关系描述了机床轻量化设计的设计流程和应用前景.最后对几种机床结构配置的创新案例进行了分析.     

Consistency in tool selection for cast iron milling

During a feasibility study of high speed machining, the tool selection is at stake. This study is supported by an industrial project, led in a French plant, where cast iron housings are machined. This paper introduces a design method enabling strategic and operational consistency in tool selection. The method is composed of two models (the model of machining systems, MOMS and the model of problem) and the design procedure. The consistency is ensured by the definition of six couples [performance element–system variable]. They are used to specify the architecture of the tool assemblies, to structure the detailed design, and to evaluate the solutions. An example is developed in the case of a precision boring.     

Roughness measurement methodology for selection of tool inserts

Contribution introduces practical methodology of roughness measurement when turning by tool inserts with variable tool face. Methodology makes the most of use standardised chip cross sections from ISO 3685:93. Measuring array consists of combination of four feeds per revolution and three depth of cut while use of two cutting speeds denotes such methodology as 4–3–2 roughness measurement. Minimum replication is used when measuring roughness in order to identify its quantities where cutting starts and stops. Data resulting from minimum replications are treated as pivot half-sums and pivot ranges, quantities following from Horn’s distribution. Four ways of results’ interpretation are expressed which include individual measured values, comparison, relationship as well as multivariate form of measured data. Individual values represent results from just one point in measuring array; comparison covers half-sum results all over measuring area. Relationships among surface roughness parameters show how roughness ranges measuring area throughout. Considerable effect of chip cross section on multivariate form of surface roughness is given by Andrews’ plot. Processing and evaluation of data give well founded information to choice proper tool insert as practical contribution related to machining plans.     

A decision support system for the selection of a rapid prototyping process using the modified TOPSIS method

As a new technology that fabricates a three-dimensional (3D) physical model from computer-aided design (CAD) data using an additive process, rapid prototyping (RP) has been developed to reduce product development time and cost. Recently, many newly emerging techniques of RP have been commercialized worldwide. This paper deals with the selection of an optimal RP system that best suits the end use of a part by using multiple-attribute decision making and the test part designed with conjoint analysis to reflect users’ preference. Evaluation factors include only the major attributes that significantly affect the performance of an RP system such as accuracy, roughness, strength, elongation, part cost and build time. Crisp values such as accuracy and surface roughness are obtained with a new test part developed in this study. The part cost and build time are identified as falling within approximate ranges due to varying costs and many variable parameters. They are presented as linguistic values that can be described with triangular fuzzy numbers. Based on the evaluation values obtained, an appropriate RP process for a specific part application can be selected using a modified technique of order preference by a similarity to ideal solution (TOPIS) method given crisp data and linguistic variables as the alternatives of attributes. Finally, each attribute’s weight is assigned using a pairwise comparison matrix. Determined using these weights, the final ranking order aids in the selection of the RP system.