A Qualitative Failure Analysis Using Function-Based Performance State-Machines for Fault Identification and Propagation During Early Design Phases

Typical, numerical structural optimization is well established in improving structural design in its final design phase. The overall product topology is then already defined and structural optimization is “only” used to improve shape and size parameters, which have no influence on the global mechanical topology. Significant decisions have been made already in earlier development stages. However, it is desirable to expand this optimization capabilities to CAE based support for the definition and preliminary design of the general layout, geometrical and structural architecture, equipment configuration and functional requirements. For satellites such a support can be defined as follows: Finding the conceptual geometrical architecture of a satellite satisfying the basic geometrical, mechanical and thermal requirements within an automated optimization process. This includes mainly the (a) topology and geometry of the basic structural components, (b) placements of basic components and equipment and (c) preliminary concept evaluation (e.g. FEM, etc.) Intentionally, the satellite design engineering team should be supplied with a set of feasible or nearly feasible satellite configurations (satisfying the main geometric, mechanical and thermal requirements) serving as a good starting basis for satellite configuration development in early design phases. The design engineers investigate these preliminary conceptual satellite designs for the remaining, typically more specific and more locally acting requirements (e.g. fastening, piping, etc...). In this way the main basic effects guiding satellite design can be taken into account at the very early development stages and, moreover, can be compared with alternative designs to find the best tradeoff. This is a great advantage and progress compared to the traditional design process. Optimization now starts to enter the early and important design phases, the real significant design decisions can now be made by support of optimization techniques. It should be further noted, that our system is not proposed to substitute the design engineers, but to supplement and to enlarge the potentials of the design branch to reach a better design in a shorter time conforming to concurrent engineering issues. In this paper our approach for an automated satellite conceptual design method will be presented, and emphasis is put on demonstration and verification by the satellite GammaBus 1 (the carrier of the Galileo system) as well as other real space applications. Further some main aspects regarding discrete-continuous optimization for structural configuration tasks from an algorithmic point of view are discussed to round out this paper

The early phase of design contains multiple sources of unexpected circumstances which include the change or addition of performance requirements or design conditions with the process of the design phases. Therefore, designers are required to design considering those unexpected circumstances in the after phases. Previously, we proposed a preference set-based design (PSD) method, which obtains a unique design solution set from a point of view of design preference and robustness under various sources of uncertainties while incorporating the designer's preference in the early phase of design. PSD method represents the uncertain design information as the interval set. This paper proposes a new design method based on PSD method which can obtain diverse possible design solution sets for unexpected circumstances by deriving the multiple feasible design domains which satisfy the required performances. Obtaining diverse possible design solution sets could deal with the unexpected circumstances by selecting the optimal design solution from obtained diverse possible design solution sets in the early phase. In this paper, the proposed design method is applied to the design problem of an active isolation system of 4-story building to correspond to the additional unexpected earthquake ground motion which the designer cannot consider at the early phase of design.

Selecting composite materials considering cost and environmental impact in the early phases of aircraft structure design

Building energy models are largely comparative in nature, from early design phase to final energy code compliance models. While there is merit in a comparative framework, with the advent of empirical compliance targets, improving the efficacy of building energy models is imperative to better align model results with future building energy consumption. To refine this alignment, even early design phase energy models should undergo proper quality checking to improve the reliability of comparative studies and yield design strategy results that will hold true in later design phases and in future building energy consumption. Subject to time or user expertise, many early design phase energy models forgo proper quality checking, which can lead to misaligned expectations when the intent for a building owner is to ultimately meet empirical compliance targets. This paper outlines an automated approach to help energy modelers efficiently quality check early design phase energy models and minimize discrepancies between comparative modeling and empirically based performance targets. The test cases presented in this paper demonstrate how quality checking improves the reliability of early comparative studies.

Building energy models are largely comparative in nature, from early design phase to final energy code compliance models. While there is merit in a comparative framework, with the advent of empirical compliance targets, improving the efficacy of building energy models is imperative to better align model results with future building energy consumption. To refine this alignment, even early design phase energy models should undergo proper quality checking to improve the reliability of comparative studies and yield design strategy results that will hold true in later design phases and in future building energy consumption. Subject to time or user expertise, many early design phase energy models forgo proper quality checking, which can lead to misaligned expectations when the intent for a building owner is to ultimately meet empirical compliance targets. This paper outlines an automated approach to help energy modelers efficiently quality check early design phase energy models and minimize discrepancies between comparative modeling and empirically based performance targets. The test cases presented in this paper demonstrate how quality checking improves the reliability of early comparative studies.

This study proposes an algorithm-aided design (AAD) framework for using daylight in the early phases of architectural design. Within the scope of the proposed AAD, a performance-based design approach has been adopted that can suggest design solutions by optimising with the Genetic Algorithm (GA) that evaluates the results obtained from daylight calculation. The AAD framework was developed using the visual programming application (Dynamo), which interoperates with BIM Software Autodesk Revit. A case study is simulated to show how the algorithm is used to generate, evaluate and evolve a massing study, demonstrating the potential use and implementation of the framework. The investigations focus on the development of the use of daylight in architecture using the advantages of computational design tools.

Purpose– Contemporary urban design has tried to account for the satisfaction of the human experience and climate change which might encompass several disciplines. However, from a methodological perspective, a systematic research approach is still lacking. Therefore, this paper aims to propose a universal research method embedded into early urban design phase with an example.Design/methodology/approach– A case study was used under the concept of DIDID Action Plan, which was proposed to integrate systematic research into urban design projects in the early phase with a focus on health and well-being. Moreover, design mapping skills tackling health risks at the population level were discussed.Findings– This proposal of DIDID Action Plan has provided inclusive steps for future urban design projects with a systematic approach, in particular for health and well-being aspect. DIDID denotes five planning stages, namely, dream, initiation, design, implementation and delivering. With the advancement of urbanisation and technology, more emphasis would be placed on health and well-being to delay chronic diseases by targeting risk contributors and to increase citizens’ quality of life and human life experience, although stopping the breakout of unexpected communicable diseases and disasters would also need to be considered from time to time as well.Practical implications– Systematic research to be integrated into early urban design phase could potentially avoid issues such as re-design and save manpower time and costs.Originality/value– This proposal is the first to provide a universal research method for early urban design phase with a focus on health and well-being.

This paper presents a design and simulation environment to support the validation of design concepts for embedded systems during early design phases. The tool is built around a methodology based on rapid prototyping. The MCEMS Toolbox supports the designer during the architectural, detailed design and implementation phase with a set of models, software and hardware for system description, prototype synthesis and execution under real-time conditions. Thus, specifications can be validated during early design phases which shortens the overall development time. >

Traditional multiphase flow simulations often include less rigorous boundary condition assumptions, because flowline models are commonly isolated from both upstream well inflow and downstream processing facilities. Such an approach can be even more unrealistic if the flowline model network is complicated for example, where connected with subsea processing equipment. Within this kind of system, changes in fluid behavior are even more sensitive to overall operability. A full field integrated simulation, which includes well inflow, subsea equipment (XTs and manifolds), subsea processing, flowlines, and/or arriving facilities, offers a more realistic solution. This paper describes the application and value of performing full field integrated simulations throughout the life-cycle phases of field development. The solver used for the simulation provides a powerful tool to screen design alternatives to identify the optimal field solution in a cost efficient way at an early design phase. In the detailed design phase the dynamic simulations using the same full field model can be performed to ensure system operability. Similarly, in the life-of-field operation phase, the same full field model can be used to perform real time metering and monitoring as well as "look-ahead" forecasting as part of an advisory system. This is usually instrumental for a challenging field production. As the simulation model evolves since early design phase until the life-of-field operation, it promotes a comprehensive continuity. "One model one solution" provides an effective design and operation tool. Such a tool is able to provide a wide range of information that is relevant across multidisciplinary teams.

This paper presents a qualitative design tool for evaluation of the risk for fluid power pitch systems. The design tool is developed with special attention to industry standard failure analysis methods and is aimed at the early phase of system design. Firstly, the concept of Fault Tree Analysis is used for systematic description of fault propagation linking failure modes to system effects. The methodology is conducted solely on a circuit diagram and functional behavior. The Failure Mode and Effects Criticality Analysis is subsequently employed to determine the failure mode risk via the Risk Priority Number. The Failure Mode and Effect Criticality Analysis is based on past research concerning failure analysis of wind turbine drive trains. Guidelines are given to select the severity, occurrence and detection score that make up the risk priority number. The usability of the method is shown in a case study of a fluid power pitch system applied to wind turbines. The results show a good agreement to recent field failure data for offshore turbines where the dominating failure modes are related to valves, accumulators and leakage. The results are further used for making design improvements to lower the overall risk of the pitch system. Copyright © 2017 John Wiley & Sons, Ltd.

During the early phases of engineering design, the costs committed are high, costs incurred are low, and the design freedom is high. It is well documented that decisions made in these early design phases drive the entire design's life cycle cost. In a traditional paradigm, key design decisions are made when little is known about the design. As the design matures, design changes become more difficult in both cost and schedule to enact. The current capability-based paradigm, which has emerged because of the constrained economic environment, calls for the infusion of knowledge usually acquired during later design phases into earlier design phases, i.e. bringing knowledge acquired during preliminary and detailed design into pre-conceptual and conceptual design. An area of critical importance to launch vehicle design is the optimization of its ascent trajectory, as the optimal trajectory will be able to take full advantage of the launch vehicle's capability to deliver a maximum amount of payload into orbit. Hence, the optimal ascent trajectory plays an important role in the vehicle's affordability posture yet little of the information required to successfully optimize a trajectory is known early in the design phase. Thus, the current paradigm of optimizing ascent trajectories involves generating point solutions for every change in a vehicle's design parameters. This is often a very tedious, manual, and time-consuming task for the analysts. Moreover, the trajectory design space is highly non-linear and multi-modal due to the interaction of various constraints. When these obstacles are coupled with the Program to Optimize Simulated Trajectories (POST), an industry standard program to optimize ascent trajectories that is difficult to use, expert trajectory analysts are required to effectively optimize a vehicle's ascent trajectory. Over the course of this paper, the authors discuss a methodology developed at NASA Marshall's Advanced Concepts Office to address these issues. The methodology is two-fold: first, capture the heuristics developed by human analysts over their many years of experience; and secondly, leverage the power of modern computing to evaluate multiple trajectories simultaneously and therefore enable the exploration of the trajectory's design space early during the pre- conceptual and conceptual phases of design. This methodology is coupled with design of experiments in order to train surrogate models, which enables trajectory design space visualization and parametric optimal ascent trajectory information to be available when early design decisions are being made.

We present a paradigm for natural and exploratory shape modeling by introducing novel 3D interactions for creating, modifying, and manipulating 3D shapes using arms and hands. Though current design tools provide complex modeling functionalities, they remain nonintuitive for novice users. Significant training is required to use these tools since they segregate 3D shapes into hierarchical 2D inputs, binding the user to stringent procedural steps and making modifications cumbersome. On the other hand, the use of computer-aided design (CAD) systems is typically involved during the final phases of design. This leaves a void in the early design phase wherein the creative exploration is critical. We present a shape creation paradigm as an exploration of creative imagination and externalization of shapes, particularly in the early phases of design. We integrate the capability of humans to express 3D shapes via hand-arm motions with traditional sweep surface representation to demonstrate rapid exploration of a rich variety of 3D shapes. We track the skeleton of users using the depth data provided by low-cost depth sensing camera (Kinect). Our modeling tool is configurable to provide a variety of implicit constraints for shape symmetry and resolution based on the position, orientation, and speed of the arms. An intuitive strategy for shape modifications is also proposed. Our main goal is to help the user to communicate the design intent to the computer with minimal effort. To this end, we conclusively demonstrate the creation of a wide variety of product concepts and show an average modeling time of a only few seconds while retaining the intuitiveness of the design process.

Failures or defects in a product will influence its quality a lot. Reducing or eliminating failures and defects in product design phase is an economical way. FMEA and BFA are two kinds of methods. By using them, the product quality and reliability can be improved in the design phase. This paper introduced a new kind of failure analysis method which was developed based on FMEA and BFA. This is a network failure model and analysis method. By using this method, the product quality could be improved and failures could be reduced.

Our goal is to provide a Multi-Perspective viewpoint interactive interface media of sketch-based for rapid get spatial layout in Show-Window. In traditional way, designer is used to describe concept in early phases of design by Single-Perspective viewpoint via sketch in Show-Window design environment. It usually makes blind spot of spatial vision in early phases of design because it can't break the Single-Perspective viewpoint. Therefore we present an interactive media of sketch-based that can get Multi-Perspective viewpoint in early phases of design to support designer. Show-Window designer not only can have synchronic interaction with object of the design environment, and have more design thinking and variability of spatial layout but also can immediate edit, revise the vision and generate an optimum spatial layout again, and reduce time cost of later phases of design by design sketch after via the interactive media.

According to the architectural parasismic concepts, the lesson brought by the last seismic events shows that a building is really parasismic only if it is the product of a close cooperation between the architect and the civil engineer as of the early phases of the design. However, the majority of the Algerian architects do not use any device tools during the earthquake designing process. This is mainly due to the inadequacy of these tools to the professionals implied in the designing process, especially the architects. They are confronted to problems and situations to which they have to find the most suitable solutions in matter of design. Their basic mission is to get hold of the maximum amount of information concerning the constraints that will serve in facilitating the designing process. Hence, the architects’ experimental skills as well as know-how are essential. The used approach in our research is based on the seismic vulnerability index method combined with fuzzy logic. The basic model is applied on seismic vulnerability assessment during the early phase of project design. The proposed method can be considered as a toolset of prediction, description, information, dialogue, decision-making, control and validation of the architectural project during the design process. The results obtained by using the designed SeVA-Tool (Seismic Vulnerability Assessment device) are very interesting. These results are included 100% in Max-reference and Min-reference of expert knowledge. Our objective is to contribute to the development of new measurement tool to save human lives against the seismic hazard.