The synthesis of functional molecular mechanisms is constrained by the notorious difficulties in fabricating nano-links of prescribed shapes and sizes. Thus, the classical mechanism synthesis methods, which assume the ability to manufacture any designed links, cannot provide a systematic process for designing molecular mechanisms. We propose a new approach to build functional mechanisms with prescribed mobility by only using elements from a predefined "link soup". The resulting synthesis procedure is the first of its kind that is capable of systematically synthesizing functional linkages with prescribed mobility constructed from a soup of primitive entities. Furthermore, the proposed systematic approach outputs the ATLAS of candidate mechanisms, which can be further processed for downstream applications. Although the scope of this technique is rather general, its immediate application is the design of molecular machines assembled from nano-links that either exist in nature or can be fabricated. For the Full Research Paper see ASME's Digital Collection.
Gwang Kim, Yunjung Kwon, Eun Suk Suh and Jaemyung Ahn J. Mech. Des 138(7), 07140; doi: 10.1115/1.4033504 This paper proposes a framework to analyze the architectural complexity of systems developed with a product family. A product family is a set of products that are derived from common sets of parts, interfaces, and processes, known as the product platform. Through the use of product platforms, several variations of products can be developed in a short period of time with relatively low-engineering costs to capture market share in niche market segments as the demand arises. This work can be used in a variety of ways to guide product platform and variant architecture development during the initial concept generation stage. The effectiveness of the proposed framework is demonstrated through a case study of a train bogie platform. The process starts with building the design structure matrix (DSM) model, which captures the structural architecture as well as mass, energy, and information flow, for the product platform and its variants. Using the DSMs created and the selected complexity metric, the architectural complexity, which includes the structural complexity and flow complexity values, is assessed. Based on the quantitative results obtained, the overall complexity for the product platform and the product family could be compared with other competing product platform architecture and product family concepts. Furthermore, this process also allows system architects and decision makers to manage overall complexity of an entire product family, either through complexity minimization or by designing the entire platform and product architecture to be less sensitive to engineering changes in terms of complexity fluctuation. For the Full Research Paper see ASME's Digital Collection.
Jessica Morgan, Spencer P. Magleby and Larry L. Howell J. Mech. Des 138(5), 052301; doi: 10.1115/1.4032973 Engineers have taken an interest in origami and developing it further for applications. Characteristics of origami of particular interest to engineers include: (1) stowability, (2) portability, (3) deployability, (4) part number reduction, (5) manufacturability from a flat sheet of material, (6) a single manufacturing technique (folding), (7) reduced assembly, (8) ease of miniaturization, and (9) low material volume and mass. Several of these attributes are of particular value in aerospace applications and it is anticipated that many more aerospace mechanisms could be developed through the use of a design process that adapts origami characteristics for use in devices and products. The research presented in this paper has two main objectives: to demonstrate that a design framework can be created to more reliably use origami patterns and principles as the basis for aerospace mechanisms and provide examples that illustrate an approach to designing origami-adapted products. This paper presents the origami-adapted design process, which is then illustrated and tested using three examples of preliminary design: an origami bellows to protect the drill shafts of a Mars Rover, an expandable habitat for the International Space Station, and a deployable parabolic antenna for space and earth communication systems. For the Full Research Paper please visit ASME's Digital Library.
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FEATURESThis section includes brief descriptions of articles soon to be or recently published by the Journal of Mechanical Design. These featured articles highlight recent research developments and emerging trends in mechanical design. For Abstracts and Full Articles please see ASME's Digital Collection. Archives
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