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Reconfigurable manufacturing systems are recognized as next generation manufacturing systems capable of providing the exact functionality and capacity as and when required. The reconfiguration of the system depends upon the ease with which any machine can be added, removed or re-adjusted for upcoming configuration from any initial or outgoing configuration. The efforts required while changing any existing configuration to a new configuration have serious implications on the cost aspect as well. The complexity and economics involved in changing one configuration to another depend on the existing initial configuration and the new upcoming configuration required for subsequent production of part families. In the present paper, based on the different types of effort associated with the reconfiguration process, a new indicator of performance termed as “Service Level” is proposed. The proposed indicator is modeled for a multipart reconfigurable manufacturing system. The proposed methodology is demonstrated using a numerical example. The values obtained for service levels while switching from one configuration to another were calculated for a serial product flow line. Some of the important implications regarding service level evaluation and implementation are finally discussed.

Tendency to optimization in last decades has resulted in creating multi-product manufacturing systems. Production planning in such systems is difficult, because optimal production volume that is calculated must be consistent with limitation of production system. Hence, integration has been proposed to decide about these problems concurrently. Main problem in integration is how we can relate production planning in medium-term timeframe with scheduling in short-term timeframe. Our contribution creates production planning and scheduling framework in flexible job shop environment with respect to time-limit of each machine in order to produce different parts families in automotive industry. Production planning and scheduling have iterative relationship. In this strategy information flow is transformed reciprocative between production planning and scheduling for satisfying time-limit of each machine. The proposed production planning has heuristic approach and renders a procedure to determine production priority of different part families based on safety stock. Scheduling is performed with ant colony optimization and assigns machine in order of priority to different part families on each frozen horizon. Results showed that, the proposed heuristic algorithm for planning decreased parts inventory at the end of planning horizon. Also, results of proposed ant colony optimization was near the optimal solution .The framework was performed to produce sixty four different part families in flexible job-shop with fourteen different machines. Output from this approach determined volume of production batches for part families on each frozen horizon and assigned different operations to machines.

Astonishingly 3D printing has excited the world of aerospace. This paper takes stock of the popular 3D printing processes in aerospace. Reasons for their popularity over the traditional manufacturing processes are dwelled upon. Materials developed specially for aerospace applications along with their characteristics are discussed. Ongoing activities related to 3D printing at various companies and organisations around the world are looked into. Project works in the area of extra-terrestrial printing are also highlighted. Even though 3D printing processes are operationally simple, they do have limitations in terms of the type, quality, and quantity of the materials they can handle. This paper underlines these points while discussing drawbacks of the printed components. Challenges associated with 3D printing in microgravity are also touched upon. Finally, a glimpse is taken into the future appearance of aerospace industry with 3D printing. [ABSTRACT FROM PUBLISHER]

Abstract: In this global manufacturing era, one of the important challenges faced by manufacturer is how to deal with stochastic demand and ever changing customer needs and requirements. Reconfigurable manufacturing systems are recognized as next generation manufacturing systems capable of providing the exact functionality and capacity as and when required. Some important performance indices studied in the past include cost, ease of reconfigurability, productivity, reliability and availability for assessing the performance of these systems. The economics while carrying out the reconfiguration process of these systems must include parameters such as cost incurred while producing orders of part families on a particular configuration and the reconfiguration cost associated while changing over from initial configuration to another. The complexity and cost involved from changing one configuration to another depends on the existing initial configuration and the new configuration required for subsequent production. In this paper, based on the different efforts associated with the reconfiguration process, a new index of performance termed as “Service Level” is proposed. The proposed indicator is modeled for a multiple part family reconfigurable manufacturing system. The methodology proposed is explained using a numerical example. The results obtained along with their important implications were discussed. [Copyright &y& Elsevier]

Cellular manufacturing system has been proved a vital approach for batch and job shop production systems. Group technology has been an essential tool for developing a cellular manufacturing system. The paper aims to discuss various cell formation techniques and highlights the significant research work done in past over the years and attempts to points out the gap in research. [ABSTRACT FROM AUTHOR]

The objective of this study is to extend the applications of reverse engineering technology from manufacturing industries to the biomedical industry. By obtaining nearly exact geometric data of human tissues, such as bones, tendons, and ligaments, in a high-speed and inexpensive manner, potentially groundbreaking research becomes possible for applications in injury rehabilitation, injury prevention and strengthening. Previous applications of reverse engineering technologies in the biomedical community have dealt largely with prosthetic design and plastic surgery. This study expands this research to include muscular and skeletal applications. The primary advantage provided by scanning technologies is an improved quality of data. Secondly, the time investment for the medical researcher is greatly reduced. And finally, the use of a scanning technology will occasionally provide a less expensive alternative to the medical imaging counterparts. The goal of the research is to develop guidelines and methodologies for reverse engineering human structures. [ABSTRACT FROM AUTHOR]

A multifamily lot-sizing and scheduling model is developed for a production environment where the production line capacity is a critical factor. Since the capacity is limited, judicious selections of family cycle times and which products of a family should be produced in a given cycle are critical in avoiding shortages. The model can be implemented using available spreadsheet programs and can be easily understood by production planners. The model was applied to a real life problem at a leading manufacturer of hygienic products. With respect to their current practice, the model resulted in a solution that was uniform in application and reduced total costs by 16%. The model was also compared against Brown's model in an uncapacitated environment. Results were encouraging, as the model performed as well as Brown's model and even better in some cases. The proposed model has an advantage over Brown's since it results in common cycle times for all product families making scheduling and controlling easier. [ABSTRACT FROM AUTHOR]

1. A new similarity coefficient measure has been developed and this coefficient measure is used to form a part-family. 2. A mathematical model that uses this similarity coefficient for solving the part-family formation problems optimally in an FMS is developed. The fuzzy approach has the special advantage of producing more accurate results than conventional clustering and other methods. It not only reveals the specific part family that a part belongs to, but also provides the degree of membership of a part associated with each part family. This will give a balanced work load for the machine. In the second part of this paper, the introduction of the concept of genetic algorithms is proposed to eliminate more job sequences and, finally, the optimum sequence is obtained through the minimum penalty cost. Software is developed and implemented to obtain an optimum sequence and, finally, a numerical example is given as an illustration. [ABSTRACT FROM AUTHOR]

Concurrent formation of part families and machine cells can be achieved by using various algorithms based on the part-machine matrix. Although, part features form the basis for the formation of the part-machine matrix, part features are not directly considered in the process of forming part families and machine cells. The goal of this paper is to understand the characteristics of machine cells in terms of part features. The relationship between part features and machine cells is captured as a decision tree. The decision tree also becomes a tool for post-clustering analysis including evaluation of different clustering methods and for the classification of ambiguous parts. The simplicity of the decision tree, the number of parts classified by each leaf of the tree, and the effect of pruning on the tree are used as metrics to evaluate the clustering methods. [ABSTRACT FROM AUTHOR]

The problem of allocating new parts to existing part families in cellular manufacturing systems is addressed in this paper. A part-family identification model is proposed to develop a part-allocation scheme based on the tooling requirements of the parts and the tooling available on the machine tools. Using this scheme, new parts may be allocated to appropriate families based on their tooling requirements. The approach suggested in this paper is demonstrated using real data from an industrial setting. [ABSTRACT FROM AUTHOR]