Generic Functional Decomposition of an Integrated Jet Engine Mechanical Sub System Using a Configurable Component Approach

A procedure is proposed to functionally decompose an already existing integrated mechanical jet engine subsystem. An integrated sub system is a system where the same design object satisfies multiple functions: which is typically the case in aircraft engine sub systems and components. A generic decomposition method will allow implementation and use in automated design systems and will function as a means to build experiences into platforms. Using the procedure, an enhanced function-means tree (E F-M tree) consisting of functional requirements, means to satisfy the requirements and constraints was created for the integrated jet engine component. The E F-M tree is then used to generate a hierarchy of configurable components (CCs). A configurable component (CC) is a stand-alone conceptual object that contains the functional requirement, means to satisfy the requirement (or design solution) and constraints at a certain level of the E F-M tree. A specific CC hierarchy configuration results in the description of the product concerned. The usage of the CC hierarchy as design documentation as well as a template to derive other designs from is demonstrated. Finally limitations of describing product functional requirements using CC method and recommendations for further development of the method are discussed

Data analysis as the basis for improved design for additive manufacturing (DFAM)

Additive Manufacturing (AM) has a large potential to revolutionize the manufacturing industry, yet the printing parameters and part design have a profound impact on the robustness of the printing process as well as the resulting quality of the manufactured components. To control the printing process, a substantial number of parameters is measured while printing and used primarily to control and adjust the printing process in-situ. The question raised in this paper is how to benefit from these data being gathered to gain insight into the print process stability. The case study performed included the analysis of data gathered during printing 22 components. The analysis was performed with a widely used Random Forest Classifier. The study revealed that the data did contain some detectable patterns that can be used further in assessing the quality of the printed component, however, they were distinct enough so that in case the test and train sets were comprised of separate components the predictions\u27 result was very poor. The study gives a good understanding of what is necessary to do a meaningful analytics study of manufacturing data from a design perspective

Cost-efficient digital twins for design space exploration: A modular platform approach

The industrial need to predict the behaviour of radically new products brings renewed interest in how to set up and make use of physical prototypes and testing. However, conducting physical testing of a large number of radical concepts is still a costly approach. This paper proposes an approach to actively use digital twins in the early phases where the design can be largely changed. The approach is based on creating a set of digital twin modules that can be reused and recomposed to create digital twin variants. However, this paper considers that developing a digital twin can be very costly. Therefore, the approach focuses on supporting the decisions about the optimal mix of modules, and about whether a new digital twin module should be developed. The approach is applied to an industrial case derived from the collaboration with two space manufacturers. The results highlight how the design of the modular platform has an impact on the cost of the digital twin, if commonality and reusability aspects are considered. These results point at the cost-efficiency of applying a modular approach to digital twin creation, as a means to reuse the results from physical testing to validate new designs and their ranges of validit

Modelling Flexibility and Qualification Ability to Assess Electric Propulsion Architectures for Satellite Megaconstellations

The higher satellite production rates expected in new megaconstellation scenarios involve radical changes in the way design trade-offs need to be considered by electric propulsion companies. In relative comparison, flexibility and qualification ability will have a higher impact in megaconstellations compared to traditional businesses. For these reasons, this paper proposes a methodology for assessing flexible propulsion architectures by taking into account variations in market behavior and qualification activities. Through the methodology, flexibility and qualification ability can be traded against traditional engineering attributes (such as functional performances) in a quantitative way. The use of the methodology is illustrated through an industrial case related to the study of xenon vs. krypton architectures for megaconstellation businesses. This paper provides insights on how to apply the methodology in other case studies, in order to enable engineering teams to present and communicate the impact of alternative architectural concepts to program managers and decision-makers

Local treatment of a bone graft by soaking in zoledronic acid inhibits bone resorption and bone formation. A bone chamber study in rats.

ABSTRACT: BACKGROUND: Bone grafts are frequently used in orthopaedic surgery. Graft remodelling is advantageous but can occur too quickly, and premature bone resorption might lead to decreased mechanical integrity of the graft. Bisphosphonates delay osteoclastic bone resorption but may also impair formation of new bone. We hypothesize that these effects are dose dependent. In the present study we evaluate different ways of applying bisphosphonates locally to the graft in a bone chamber model, and compare that with systemic treatment. METHODS: Cancellous bone grafts were placed in titanium chambers and implanted in the tibia of 50 male rats, randomly divided into five groups. The first group served as negative control and the grafts were rinsed in saline before implantation. In the second and third groups, the grafts were soaked in a zoledronic acid solution (0.5 mg/ml) for 5 seconds and 10 minutes respectively before being rinsed in saline. In the fourth group, 8 μL of zoledronic acid solution (0.5 mg/ml) was pipetted onto the freeze-dried grafts without rinsing. The fifth group served as positive control and the rats were given zoledronic acid (0.1 mg/kg) systemically as a single injection two weeks after surgery. The grafts were harvested at 6 weeks and analysed with histomorphometry, evaluating the ingrowth distance of new bone into the graft as an equivalent to the anabolic osteoblast effect and the amount (bone volume/total volume; BV/TV) of remaining bone in the remodelled graft as equivalent to the catabolic osteoclast effect. RESULTS: In all chambers, almost the entire graft had been revascularized but only partly remodelled at harvest. The ingrowth distance of new bone into the graft was lower in grafts soaked in zoledronic acid for 10 minutes compared to control (p = 0.007). In all groups receiving zoledronic acid, the BV/TV was higher compared to control. CONCLUSIONS: This study found a strong inhibitory effect on bone resorption by bisphosphonates but also a limited inhibition of the ingrowth of new bone. Local treatment at surgery resulted in stronger inhibition of both resorption and bone formation compared to systemic treatment

Fuzzy model-based design for testing and qualification of additive manufacturing components

The uncertainties and variation of additive manufacturing (AM) material properties and their impact on product quality trouble designers. The lack of experience in AM technologies renders the experts\u27 assessment of AM components and the establishment of safety margins difficult. Consequently, unexpected qualification difficulties resulting in expensive and lengthy redesign processes might arise. To reduce the risk of qualification failure, engineers might perform copious time-consuming and expensive specimen testing in early phases, or establish overconservative design margins, overriding the weight reduction benefits of AM technologies. In this article, a model-based design method is proposed for the conceptual design of AM space components with affordable test phases. The method utilizes fuzzy logics to systematically account for experts\u27 assessment of AM properties variation, and to provide an early estimation of a product qualification likelihood related to design parameters of interest, without the need for copious testing. The estimation of qualification likelihood can also point out which are the unique AM material uncertainties that require further specific testing, to enable the design of a product with a better performance and more affordable test phases. The method is demonstrated with the design for AM gridded of ion thrusters for satellite applications

Enabling organizational changes for development of product-service system offers

The manufacturing industry is going through a transition from developing of products to the provision of product-service systems (PSS). Earlier research has identified different types of PSS offers, from product offers that include services as “add-on”, to the sale of services that include tangible goods as “add-on”. This paper addresses what consequences this has on manufacturing organizations undergoing PSS transition. The purpose of the paper is to clarify key success factors for organizational changes needed in the transition process of developing different types of PSS offers. The results are based on a case study of a manufacturer in the aerospace domain; the analysis approached organizational changes from organizational theory perspective. The study identified four key areas that need to be considered in the organizational transformation to PSS development: Business strategy and decision-making, Internal organizational structure, Team composition, and External networks and customer relationship. Based on the analysis of empirical data from these four areas, the paper discusses the successful organizational changes that are required in the transition towards PSS development

Function model-based generation of CAD model variants

A product is an artefact which fulfils a specific function. However, most design automation (DA) approaches wich are used to generate multiple alternative design concepts focus on the generation of CAD models. These neglect to represent the functional aspects of the product, and are furthermore deemed too rigid for the introductino of novel solutions. Pure function modellingappraoches on the other hand provides methods such as design rationale representation, introduction of novel solutions or instantiation of combinatorial alternative concepts, but the resulting models are insufficient for analysis. To alleviate this, a design space exploration (DSE) approach which couples function modelling and CAD is presented. The approachlinks the product’s design rationale modelled in enhanced functionmeans (EF-M) to a DA approach via the here introduced object model for function and geometry (OMFG). The resulting method is able to automatically generate CAD models of alternative concepts based on combinations of alternative design solutions defined in the function model. The approach is presented through a case study of an aircraft engine component. Sixteen different concepts are generated based on four functions with alternative solutions. In an initial computation of the effort to generate all alternative concepts, the DA aspect of the approach’s effort pays off as soon as five functions have two or more alternative solutions. Beyond the benefit of efficient instantiation of CAD models of alternative product concepts, the approach promises to provide the design rationale behind each concept, and thereby a more systematic way of exploring and evaluating alternative design concepts

Design space exploration of a jet engine component using a combined object model for function and geometry

The design of aircraft and engine components hinges on the use of computer aided design (CAD) models and the subsequent geometry-based analyses for evaluation of the quality of a concept. However, the generation (and variation) of CAD models to include radical or novel design solutions is a resource intense modelling effort. While approaches to automate the generation and variation of CAD models exist, they neglect the capture and representation of the product’s design rationale—what the product is supposed to do. The design space exploration approach Function and Geometry Exploration (FGE) aims to support the exploration of more functionally and geometrically different product concepts under consideration of not only geometrical, but also teleological aspects. The FGE approach has been presented and verified in a previous presentation. However, in order to contribute to engineering design practice, a design method needs to be validated through application in industrial practice. Hence, this publication reports from a study where the FGE approach has been applied by a design team of a Swedish aerospace manufacturers in a conceptual product development project. Conceptually different alternatives were identified in order to meet the expected functionality of a guide vane (GV). The FGE was introduced and applied in a series of workshops. Data was collected through participatory observation in the design teams by the researchers, as well as interviews and questionnaires. The results reveal the potential of the FGE approach as a design support to: (1) Represent and capture the design rationale and the design space; (2) capture, integrate and model novel solutions; and (3) provide support for the embodiment of novel concepts that would otherwise remain unexplored. In conclusion, the FGE method supports designers to articulate and link the design rationale, including functional requirements and alternative solutions, to geometrical features of the product concepts. The method supports the exploration of alternative solutions as well as functions. However, scalability and robustness of the generated CAD models remain subject to further research

WORKING AGILE TO SPEED UP RESEARCH WITH INDUSTRY: FIVE INDEPENDENCE PRINCIPLES

One of the obstacles to the ability of research to make an impact on industry resides on the research process itself. Today, there is a need to accelerate the means for research to support industrial transformation. At the same time, there is the need to maintain scientific rigorousness, which often requires time. To solve this trade-off, this paper evaluates existing research approaches through the lenses of agile development. The analysis is based on a simulation of research process architectures, and on observations made over several research projects with industry. The results of this analysis highlight five light-but-sufficient rules of research project behavior to keep momentum, motivation and trust when doing research with industry. The paper demonstrates the use of these five rules in a research sprint conducted iwith two automotive OEMs