36 research outputs found
A V-Diagram for the Design of Integrated Health Management for Unmanned Aerial Systems
Designing Integrated Vehicle Health Management (IVHM) for Unmanned Aerial Systems (UAS) is inherently complex. UAS are a system of systems (SoS) and IVHM is a product-service, thus the designer has to take into account many factors, such as: the design of the other systems of the UAS (e.g. engines, structure, communications), the split of functions between elements of the UAS, the intended operation/mission of the UAS, the cost verses benefit of monitoring a system/component/part, different techniques for monitoring the health of the UAS, optimizing the health of the fleet and not just the individual UAS, amongst others. The design of IVHM cannot sit alongside, or after, the design of UAS, but itself be integrated into the overall design to maximize IVHM’s potential.
Many different methods exist to help design complex products and manage the process. One method used is the V-diagram which is based on three concepts: decomposition & definition; integration & testing; and verification & validation. This paper adapts the V-diagram so that it can be used for designing IVHM for UAS. The adapted v-diagram splits into different tracks for the different system elements of the UAS and responses to health states (decomposition and definition). These tracks are then combined into an overall IVHM provision for the UAS (integration and testing), which can be verified and validated. The stages of the adapted V-diagram can easily be aligned with the stages of the V-diagram being used to design the UAS bringing the design of the IVHM in step with the overall design process. The adapted V-diagram also allows the design IVHM for a UAS to be broken down in to smaller tasks which can be assigned to people/teams with the relevant competencies. The adapted V-diagram could also be used to design IVHM for other SoS and other vehicles or products
A through-life costing methodology for use in product-service-systems
Availability-based contracts which provide customers with the use of assets such as machines, ships, aircraft platforms or subsystems like engines and avionics are increasingly offered as an alternative to the purchase of an asset and separate support contracts. The cost of servicing a durable product can be addressed by Through-life Costing (TLC). Providers of advanced services are now concerned with the cost of delivering outcomes that meet customer requirements using combinations of assets and activities via a Product Service System (PSS). This paper addresses the question: To what extent are the current approaches to TLC methodologically appropriate for costing the provision of advanced services, particularly availability, through a PSS? A novel methodology for TLC is outlined addressing the challenges of PSS cost assessment with regard to 'what?' (cost object), 'why/to what extent?' (scope and boundaries), and 'how?' (computations). The research provides clarity for those seeking to cost availability in a performance-orientated contractual setting and provides insight to the measures that may be associated with it. In particular, a reductionist approach that focuses on one cost object at a time is not appropriate for a PSS. Costing an advanced service delivered through a PSS is a problem of attributing the value of means to the economic activities carried out for specific ends to be achieved. Cost results from the interplay between monetary and non-monetary metrics, and uncertainties thereof. Whilst seeking to ensure generality of the findings, the application of TLC examined here is limited to a military aircraft platform and subsystems. © 2014 Elsevier B.V. All rights reserved
Enhanced EO Wavelength Conversion Using Slow Light
Slow light in photonic crystals can be used to increase the efficiency of nonlinear processes. The increased electric field near internal resonances increases the efficiency of parametric interactions such as harmonic up-conversion and down-conversion to the IR, and provides a versatile method for phase-matching. This review describes the theoretical background and experimental results reported in recent literature for semiconductor photonic crystals, optical fibres and waveguides. Prospects for efficient parametric converters with low pump power requirements are discussed
Börstler J.: The FAR Approach - Functional Analysis/Allocation and Requirements Flowdown Using Use Case Realizations
Abstract. This paper describes a use case driven approach for functional analysis/allocation and requirements flowdown. The approach utilizes use cases and use case realizations for functional architecture modeling, which in turn form the basis for design synthesis and requirements flowdown. We refer to this approach as the FAR (Functional Architecture by use case Realizations) approach. The FAR approach is currently applied in several large-scale defense projects within BAE Systems Hägglunds AB and the experience so far is quite positive. The approach is illustrated throughout the paper using the well known Automatic Teller Machine (ATM) example
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An investigation into the potential use of social media technologies to improve the product development functions within the aerospace and defence industry
Competition in global markets has resulted in increased demands for improvements in manufacturing processes. Enterprises have to re-engineer work practices and have shown that the effective communication of knowledge is fundamental to Product Development (PD). It is vital that cross-functional internal and external collaboration is optimised within PD processes and this should be facilitated through early, frequent and effective communication of information and knowledge. Social Media sites represent a new stage in the evolution of the Internet. Sites such as Facebook and Twitter, offer users the ability to stay connected online with friends and colleagues around the world in real-time; similarly, they offer the ability to locate expertise, knowledge and solutions to problems. The results of an industrial investigation, carried out within a leading aerospace and defence organisation, are commented upon and an interactive groupware solution is introduced, which aims to facilitate collaboration between dispersed product development teams