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1 – 10 of 285Nicholas A. Meisel, Christopher B. Williams, Kimberly P. Ellis and Don Taylor
Additive manufacturing (AM) can reduce the process supply chain and encourage manufacturing innovation in remote or austere environments by producing an array of replacement/spare…
Abstract
Purpose
Additive manufacturing (AM) can reduce the process supply chain and encourage manufacturing innovation in remote or austere environments by producing an array of replacement/spare parts from a single raw material source. The wide variety of AM technologies, materials, and potential use cases necessitates decision support that addresses the diverse considerations of deployable manufacturing. The paper aims to discuss these issues.
Design/methodology/approach
Semi-structured interviews with potential users are conducted in order to establish a general deployable AM framework. This framework then forms the basis for a decision support tool to help users determine appropriate machines and materials for their desired deployable context.
Findings
User constraints are separated into process, machine, part, material, environmental, and logistical categories to form a deployable AM framework. These inform a “tiered funnel” selection tool, where each stage requires increased user knowledge of AM and the deployable context. The tool can help users narrow a database of candidate machines and materials to those appropriate for their deployable context.
Research limitations/implications
Future work will focus on expanding the environments covered by the decision support tool and expanding the user needs pool to incorporate private sector users and users less familiar with AM processes.
Practical implications
The framework in this paper can influence the growth of existing deployable manufacturing endeavors (e.g. Rapid Equipping Force Expeditionary Lab – Mobile, Army’s Mobile Parts Hospital, etc.) and considerations for future deployable AM systems.
Originality/value
This work represents novel research to develop both a framework for deployable AM and a user-driven decision support tool to select a process and material for the deployable context.
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S. Vinodh, T. Selvaraj, Suresh Kumar Chintha and Vimal K E K
– This paper aims to apply Value Stream Mapping (VSM) for enabling leanness in an Indian automotive components manufacturing organization.
Abstract
Purpose
This paper aims to apply Value Stream Mapping (VSM) for enabling leanness in an Indian automotive components manufacturing organization.
Design/methodology/approach
The study was initiated with the selection of product line, construction of current state map, identification of various wastes and the development of future state map. The improvement proposals were subjected to implementation and performance measures were quantified.
Findings
The expected outcomes of the study include the quantification of wastes, improvement in manpower productivity, quality improvement and throughput time reduction.
Research limitations/implications
The implementation study has been conducted in only one manufacturing organization. The experiences gained by the conduct of this implementation study are feasible and deployable in similar manufacturing organizations.
Practical implications
The results of the study indicated that significant improvement in lean characteristics is possible as a result of the implementation of VSM.
Originality/value
The paper reports a real-time study conducted in an automotive components manufacturing organization. Hence, the contributions are original.
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Xiaojun Wang, Zhenxian Luo and Xinyu Geng
This paper is to present an experiment to verify that the motion errors of robust topology optimization results of compliant mechanisms are insensitive to load dispersion.
Abstract
Purpose
This paper is to present an experiment to verify that the motion errors of robust topology optimization results of compliant mechanisms are insensitive to load dispersion.
Design/methodology/approach
First, the test pieces of deterministic optimization and robust optimization results are manufactured by the combination of three-dimensional (3D) printing and casting techniques. To measure the displacement of the test piece of compliant mechanism, a displacement measurement method based on the image recognition technique is proposed in this paper.
Findings
According to the experimental data analysis, the robust topology optimization results of compliant mechanisms are less sensitive to uncertainties, comparing with the deterministic optimization results.
Originality/value
An experiment is presented to verify the effectiveness of robust topology optimization for compliant mechanisms. The test pieces of deterministic optimization and robust optimization results are manufactured by the combination of 3D printing and casting techniques. By comparing the experimental data, it is found that the motion errors of robust topology optimization results of compliant mechanisms are insensitive to load dispersion.
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Anna Maria Mazur, Jens ten Thije, Joost Vreeken, Henk Hesselink, Bartosz Dziugieł, Sylwester Wyka, Adam Liberacki, Teresa Idzikowska, Anna Dorota Stanczyk, Agata Utracka, Piotr Ginter, Sandra Czupryn, Michele Giannuzzi, Sandra Melo, Adriana Witkowska-Konieczny, Vittorio Di Vito and Aniello Menichino
The purpose of this paper is to study the overall framework in which the Urban Air Mobility (UAM) deployment is expected to be implemented. Another aim of the study is to give a…
Abstract
Purpose
The purpose of this paper is to study the overall framework in which the Urban Air Mobility (UAM) deployment is expected to be implemented. Another aim of the study is to give a better overview on the current regulations and standards including the impact of the regulations on the industry, operations and cities.
Design/methodology/approach
This paper performs a literature review on the regulatory framework, which provides a clear view of the current regulations and standards. The review includes the insight into the details of possible international rules for the future, considering operations in the specific and certified categories. The impact and trends of current and future regulations are also presented.
Findings
The analysis described in this paper shows a strong upward trend in UAM technical and operational developments as well as further potential for a successful incorporation in city mobility concepts. This paper indicates the importance of the representatives of guideline development organizations, industry, agencies and other important players involved in the standard development process.
Practical implications
This section describes synthesis on the required level of safety for UAM operations as well as description on the impact of the regulations from different perspectives, including industry and certification of urban aircraft, operations and air traffic management, cities and the governance of the urban airspace and well as technology.
Originality/value
Barriers such as legislation do not allow the common UAM to be deployed. This paper studies the overall framework in which the UAM deployment is expected to be implemented.
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Jianran Lv, Hongyao Shen and Jianzhong Fu
3D printing for objects whose size exceeds the scope of the printer is still a tough challenge in application. The purpose of this paper is to propose a visual stitching…
Abstract
Purpose
3D printing for objects whose size exceeds the scope of the printer is still a tough challenge in application. The purpose of this paper is to propose a visual stitching large-scale (VSLS) 3D-printing method to solve this problem.
Design/methodology/approach
The single segmentation point method and multiple segmentation point method are proposed to adaptively divide each slice of the model into several segments. For each layer, the mobile robot will move to different positions to print each segment, and every time it arrives at the planned location, the contours of the printed segments are captured with a high-definition camera by the feature point recognition algorithm. Then, the coordinate transformation is implemented to adjust the printing codes of the next segment so that each part can be perfectly aligned. The authors print up layer by layer in this manner until the model is complete.
Findings
In Section 3, two specimens, whose sizes are 166 per cent and 252 per cent of the scope of the 3D-printing robot, are successfully printed. Meanwhile, the completed models of the specimens are printed using a suitable traditional printer for comparison. The result shows that the specimens in the test group have basically identical sizes to those in the control group, which verifies the feasibility of the VSLS method.
Originality/value
Unlike most of the current solutions that demand harsh requirement for positioning accuracy of the mobile robots, the authors use a camera to compensate for the lost positioning accuracy of the device during movement, thereby avoiding precise control to the device’s location. And the coordinate transformation is implemented to adjust the printing codes of the next sub-models so that each part can be aligned perfectly.
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Ligang Lu, Pengfei Li, Dongbo Wu, Jiawei Liang, Hui Wang and Pengpeng He
The purpose of this study is to establish an assembly accuracy analysis model of deployable arms based on Jacobian–Torsor theory to improve the assembly accuracy. Spacecraft…
Abstract
Purpose
The purpose of this study is to establish an assembly accuracy analysis model of deployable arms based on Jacobian–Torsor theory to improve the assembly accuracy. Spacecraft deployable arm is one of the core components of spacecraft. Reducing the errors in assembly process is the main method to improve the assembly accuracy of spacecraft deployable arms.
Design/methodology/approach
First, the influence of composite connecting rod, root joint and arm joint on assembly accuracy in the tandem assembly process is analyzed to propose the assembly accuracy analysis model. Second, a non-tandem assembly process of “two joints fixed-composite rod installed-flange gasket compensated” is proposed and analyzed to improve the assembly accuracy of deployable arms. Finally, the feasibility of non-tandem assembly process strategy is verified by assembly experiment.
Findings
The experiential results show that the assembly errors are reduced compared with the tandem assembly process. The errors on axes x, y and z directions decreased from 14.1009 mm, 14.2424 mm and 0.8414 mm to 0.922 mm, 0.671 mm and 0.2393 mm, respectively. The errors round axes x and y directions also decreased from 0.0050° and 0.0053° to 0.00292° and 0.00251°, respectively.
Originality/value
This paper presents an assembly accuracy analysis model of deployable arms and applies the model to calculate assembly errors in tandem assembly process. In addition, a non-tandem assembly process is proposed based on the model. The experimental results show that the non-tandem assembly process can improve the assembly accuracy of deployable arms.
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Ashutosh Tiwari, Chris Turner and Peter Sackett
The techniques that help organisations implement leading edge cost and quality practices in manufacturing operations management are typically disparate and generic in nature…
Abstract
Purpose
The techniques that help organisations implement leading edge cost and quality practices in manufacturing operations management are typically disparate and generic in nature. There is a need to identify integrated practices at the right level of granularity, based on a clear definition of the existing operations practices. This paper proposes a novel framework for achieving and maintaining good cost and quality operations management practice within a manufacturing environment.
Design/methodology/approach
The framework uses a new approach for identifying the profile of current activities and better practice activities for the roles of team leaders, cell leaders and operations managers within a manufacturing company.
Findings
The paper proposes a recommended set of context‐specific activities for these roles. These recommended activities are utilised to develop a cascade of deployable recommendations.
Originality/value
The framework is illustrated within a manufacturing environment producing complex product ranges. The implementation of the framework enables improved operational efficiency and effectiveness. It also enables the benefits of improved operational standardisation and consistency.
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Uma Maheshwaraa Namasivayam and Carolyn Conner Seepersad
Solid freeform fabrication is particularly suitable for fabricating customized parts, but it has not been used for fabricating deployable structures that can be stored in a…
Abstract
Purpose
Solid freeform fabrication is particularly suitable for fabricating customized parts, but it has not been used for fabricating deployable structures that can be stored in a compact configuration and deployed quickly and easily in the field. The purpose of this paper is to present a methodology for deploying flexible, freeform structure with lattice skins as the deploying mechanism.
Design/methodology/approach
A ground structure‐based topology optimization procedure is utilized, with a penalization scheme that encourages convergence to sets of thick lattice elements that are manufacturable and extremely thin lattice elements that are removed from the final structure.
Findings
A deployable wing is designed for a miniature unmanned aerial vehicle. A physical prototype of the optimal configuration is fabricated with selective laser sintering and compared with the virtual prototype. The proposed methodology results in a 78 percent improvement in deviations from the intended surface profile of the deployed part.
Originality/value
The results presented in the paper provide proof‐of‐concept for the use of lattice skins as a deployment mechanism. A topology optimization framework is also provided for designing these lattice skins. Potential applications include portable, camouflaged shelters and deployable aerial vehicles.
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Hongyue Zhao, Chuang Shi, Hongwei Guo and Rongqiang Liu
In order to make the aperture of spatial deployable antenna larger, this paper proposed the study on a spatial annular tensegrity structure with 100 m large scale, which could be…
Abstract
Purpose
In order to make the aperture of spatial deployable antenna larger, this paper proposed the study on a spatial annular tensegrity structure with 100 m large scale, which could be one of the ideal solutions to improve the dimension of the antenna. This study is aiming to figure out the dynamic characteristic of ultra-large annular tensegrity and address the problem of insufficient rigidity with local modes that many ring truss-type deployable antenna structures have faced.
Design/methodology/approach
This work is carried out based on the nonlinear dynamic modelling when fully considering the effect of bending and torsion deformation of beams, as well as the pretension of cables. Additionally, the structural stability analysis based on the proposed stability criterion is also presented to evaluate the tensegrity configuration with different distribution of cable groups.
Findings
This research results verify that the modified structure with radial ribs could eliminate the effect of the local vibration mode on stiffness and is suitable to meet the requirements of the annular tensegrity structure. Additionally, the calculation results demonstrate that the structural configuration of annular tensegrity with 36 groups of cables which share the nodes with radial ribs is more appropriate to enhance the stiffness and structural stability.
Originality/value
A new large annular tensegrity structure with radial ribs and tensioned cables is proposed. Based on the proposed structural configuration, the positive definiteness of the tangent stiffness matrix is carried out as the criterion of stability and the composition of the analytical expression of the tangent stiffness matrix is analyzed. Four levels of tensegrity structure stability have been carried out and the influence of the structural parameters on the stability and the rigidity has been analyzed. A scaled-down prototype is developed to verify the feasibility of the design of the hoop-column-rib configuration by the deployment and dynamic experiment.
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Christian F. Durach and José A.D. Machuca
The purpose of this paper is to, first, explore the role of interpersonal relationships between buying and supplying firms in the management of supply chain disruptions (SCDs)…
Abstract
Purpose
The purpose of this paper is to, first, explore the role of interpersonal relationships between buying and supplying firms in the management of supply chain disruptions (SCDs). Interpersonal connections are proposed as “social lubricants” that can advance the knowledge about conventional interorganizational antecedents of firm resilience. Differentiating between high- and low-complexity manufacturing industries, the study then looks into how managers from these industry clusters can leverage the efficacy of these relationships through the appropriate use of interorganizational governance mechanisms.
Design/methodology/approach
Structural equation modeling is conducted with data collected from 229 manufacturing firms in Austria, Germany and Switzerland. Industry clusters are formed via a Q-sort exercise.
Findings
Results support the assumption of a socially embedded, interpersonal dimension in buyer-supplier relationships that impact organizational-level resilience. It is suggested that investments in interpersonal skills and interpersonal complementarity are significant antecedents of both relational and re-deployable firm resilience. Surprisingly, no support was found for a positive impact of interpersonal information sharing on firm resilience, challenging findings from previous studies on an interorganizational level. Interorganizational governance and industry affiliation each have moderating effects on the performance of the resilience efficacy of interpersonal relationship antecedents, suggesting the existence of an important managerial lever.
Originality/value
Integrating the supply chain and behavioral science literature, this study is the first to investigate the interplay of interpersonal and organizational antecedents and their efficacy in the management of SCDs.
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