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Cellular manufacturing is the organisation of manufacturing equipment based on the requirements of the product or component. Transition to cellular manufacturing generally requires reorganisation of existing equipment. It is likely that the existing equipment alone is not suitable for a cellular layout. During the cell planning and design phase equipment investment analysis is important to identify equipment needs. Transition from job shop production to cellular production is detailed. Cell formation and cell evaluation techniques are provided to assist in equipment procurement decisions. In particular, a structured procedure and analytical tools are given to evaluate fully the cellular system to identify appropriate equipment and methods. A case example is provided to explain the procedure.

The introduction of cellular manufacture in two factories is examined. In the first factory, the economic difficulties driving the changes were anticipated rather than being felt. Its most pressing problem was how to divide its products into the “families” necessary for cellular production. It was decided that this division should to some extent determine what products should be produced rather than vice versa. For the second factory, where economic difficulties were already present, the stage had been reached at which it had to be decided who was to work in the cells. Though the decisions had been made, they had not been communicated to the workforce for fear of disrupting current production. In both cases it can be seen that in order to gain the benefits of cellular manufacture, fundamental changes have to be made not only in the production process but also in the management of human resources.

In today’s competitive market, product demand and its mix frequently vary due to various uncertainties, which thus imparts the overall manufacturing cost. Furthermore, uncertainties also impart the layout design in manufacturing industries in the long run. Therefore, the layout design needs to capture the possibility of uncertainties, and these uncertainties must be captured while designing the layout of a facility. Hence, an efficient facility layout design minimizes the manufacturing cost and lead time. The purpose of this paper is to propose a cellular layout design for a tower manufacturing industry.

The paper develops an embedded simulated annealing-based meta-heuristic to solve proposed cellular layout under different scenarios considering single and multi-time periods for tower manufacturing industry. A comparative study is also performed to analyze comparison among static cellular layout, a dynamic cellular layout or a robust stochastic cellular layout for the tower manufacturing industry.

The current layout of the industry is a process layout. Here, the layout for a tower manufacturing industry is proposed under SCFLP, DCFLP and RSCFLP. The proposed models and solution methodology is tested using six scenarios with different combination of time periods. Lastly, OFV value obtained for all the scenarios is compared, and it is found that RSCFLP outruns other SCFLP and DCFLP for a tower manufacturing industry. Based on the above study, it is also concluded that RSCFLP is an efficient and effective layout in tower manufacturing industry.

The paper proposes a cellular layout design for a tower manufacturing industry. The cellular layout design is found to be preferred over the traditional layout as it reduces material handling cost, manufacturing lead time and hazards. Moreover, it enhances productivity and quality.

Composite cellular structures have wide application in advanced engineering fields due to their high specific stiffness and strength. As an emerging technology, continuous fiber-reinforced polymer additive manufacturing provides a cost-effective solution for fabricating composite cellular structures with complex designs. However, the corresponding path planning methods are case-specific and have not considered any manufacturing constraints. This study aims to develop a generally applicable path planning method to fill the above research gap.

This study proposes a path planning method based on the graph theory, yielding an infill toolpath with a minimum fiber cutting frequency, printing time and total turning angle. More specifically, the cellular structure design is converted to a graph first. Then, the graph is modified to search an Eulerian path by adding an optimal set of extra edges determined through the integer linear programming method. Finally, the toolpath with minimum total turning angle is obtained with a constrained Euler path search algorithm.

The effectiveness of the proposed method is validated through the fabrication of both periodic and nonperiodic composite cellular structures, i.e. triangular unit cell-based, Voronoi diagram-based and topology optimized structures. The proposed method provides the basis for manufacturing planar thin-walled cellular structures of continuous fiber-reinforced polymer (CFRP). Moreover, the proposed method shows a notable improvement compared with the existing method. The fiber cutting frequency, printing time and total turning angle have been reduced up to 88.7%, 52.6% and 65.5%, respectively.

A generally applicable path planning method is developed to generate continuous toolpaths for fabricating cellular structures in CFRP-additive manufacturing, which is an emerging technology. More importantly, manufacturing constraints such as fiber cutting frequency, printing time and total turning angle of fibers are considered within the process planning for the first time.

Additive manufacturing (AM), a rapidly evolving paradigm, has shown significant advantages over traditional subtractive processing routines by allowing for the custom creation of structural components with enhanced performance. Numerous studies have shown that the technical qualities of AM components are profoundly affected by the discovery of novel metastable substructures in diverse alloys. Therefore, the purpose of this study is to determine the effect of cell structure parameters on its mechanical response.

Initially, a methodology was suggested for testing porous materials, focusing on static tensile testing. For a qualitative evaluation of the cellular structures produced, computed tomography (CT) was used. Then, the CT scanner was used to analyze a sample and determine its actual relative density, as well as perform a detailed geometric analysis.

The experimental research demonstrates that the mechanical properties of a cell’s structure are significantly influenced by its shape during formation. It was also determined that using selective laser melting to produce cell structures with a minimum single-cell size of approximately 2 mm would be the most appropriate method.

Further studies of cellular structures for testing their static tensile strength are planned for the future. The study will be carried out for a larger number of samples, taking into account a wider range of cellular structure parameters. An important step will also be the verification of the results of the static tensile test using numerical analysis for the model obtained by CT scanning.

The fabrication of metallic parts with different cellular structures is very important with a selective laser melted machine. However, the determination of cell size and structure with mechanical properties is quiet novel in this current investigation.

This paper is aimed at comparing cellular manufacturing with focused cellular manufacturing. We define focused cellular manufacturing as a layout scheme that groups components by end‐items and forms cells of machines to fabricate and assemble end‐items. It is not classified as a cellular manufacturing layout since it does not attempt to take advantage of process similarities. It also is not classified as a flow shop since there are no machines dedicated to individual operations and the machines are not arranged in a series. In addition, this research includes batching and assemble times in its criteria which few researchers in this area have done. The results indicate that the focused cellular manufacturing scheme has a batching advantage. This advantage out‐weighed the set‐up time reduction advantage of the cellular manufacturing scheme for average end‐item completion times and average work‐in‐process inventory levels. The cellular manufacturing scheme overcame the batching advantage only when there were small batch sizes or large set‐up time magnitudes.

Contrasts functional layouts and cellular layouts with regard to the effects of set‐up time reduction and lot size on flow time and through‐put. The structural environment for the functional analysis is an efficient functional system with a staged sequence of four machine centers with unidirectional flow and no backtracking. The structural environment for the cellular analysis is a partitioned cell consisting of one machine from each of the four machine types with unidirectional flow and no backtracking. Simulation models produce robust results for eight lot size levels and one (functional model) and seven (cellular model) set‐up time reduction levels. The results contrast the effectiveness of the two manufacturing approaches under differing input conditions. Shows that the choice between the functional structure and the cellular structure significantly affects through‐put at lot sizes up to 55, while for lot sizes of 60 and above there is no significant effect. The study also confirms previous results regarding the effect of manufacturing structure choice on flow time.

Without reliance on results obtained from applying a cell formation method, this paper aims to describe a simple quantitative approach to testing whether an underlying pattern of relationships exists between machines of a given system, such that the machines may be rearranged into manufacturing cells. It also aims to support the approach by an index for measuring the clustering tendency.

The eigenvalues of the similarity coefficient matrix and Kaiser's rule are used to: detect the number of clusters existing in the part‐machine matrix, and derive an index for predicting the goodness of the best possible obtainable cell formation.

The results of applying the proposed approach and the clustering tendency index to problems of different sizes taken from the literature have proven that both the approach and the clustering tendency index are powerful in performing the feasibility assessment and in predicting the right number of manufacturing cell to be formed.

This study is of considerable value to practitioners because it provides them with a powerful yet very easy to apply approach for assessing the feasibility of adopting cellular manufacturing in early stages of design. Another characteristic of this approach is the possibility of using it as a decision support tool for practitioners who opt to use a cell formation method which requires specifying the number of cells in advance. Moreover, the approach does not require any special software package, since it can be easily performed using several available software packages such as MATLAB and Mathematica.

A methodology for evaluating the adaptability of a system to cellular manufacturing has been proposed in a previous study. However, the methodology used is complex and uses a certain degree of subjectivity. In contrast, the proposed approach is simple and completely quantitative. Furthermore, a new index for measuring the clustering tendency is presented.

This study aims to focus on the optimized design and mechanical properties of gradient triply periodic minimal surface cellular structures manufactured by selective laser melting.

Uniform and gradient IWP and primitive cellular structures have been designed by the optimized function in MATLAB, and selective laser melting technology was applied to manufacture these cellular structures. Finite element analysis was applied to optimize the pinch-off problem, and compressive tests were carried out for the evaluation of mechanical properties of gradient cellular structures.

Finite element analysis shows that the elastic modulus of IWP increased as design parameter b increased, and then decreased when parameter b is higher than 5.5. The highest elastic modulus of primitive increased by 89.2% when parameter b is 6. The compressive behavior of gradient IWP and primitive shows a layer-by-layer way, and elastic modulus and first maximum compressive strength of gradient primitive are higher than that of gradient IWP. The effective energy absorption of gradient cellular structures increased as the average porosity decreased, and the effective energy absorption of gradient primitive is about twice than that of gradient IWP.

This paper presents an optimized design method for the pinch-off problem of gradient triply periodic minimal surface cellular structures.

Describes how elements of the learning organization model can be found in Pratt & Whitney as the company embraces cellular manufacturing. Emphasizes the integration of traditional support groups into cell‐oriented business units. Argues that units experiencing the largest productivity gains have successfully completed the necessary integration. Reveals how productive units have changed their cultures from strict hierarchical control to high employee involvement. Suggests that units within the company which are still struggling with the necessary integration have yet to become learning organizations. Asserts that the challenge for Pratt & Whitney is to expand its successes throughout the company. Concludes that Pratt & Whitney is on track to achieve institutionalized learning and that achieving institutionalized learning requires adoption of the five learning organization tenets throughout the company.