Function allocation theory for creative design

Function structure influences on systems architecture (or product architecture). This paper discusses a design method for creative design solutions that focuses on the allocation of functions. It first proposes a theory called “Function Allocation Theory” to allocate a function to an appropriate subsystem or component during the systems decomposition phase. By doing so, the complexity of design solutions can be reduced. The theory is applied to some examples including collaborative robots and robotics maintenance. Finally, the paper illustrates a case study of designing a reaction-free fastening system using this theory

Functional modelling in evolvable assembly systems

The design and reconfiguration of adaptive production systems is a key driver in modern advanced manufacturing. We summarise the use of an ap-proach from the field of functional modelling to capture the function, behaviour, and structure of a system. This model is an integral part of the Evolvable Assembly Systems architecture, allowing the system to adapt its behaviour in response to changing product requirements. The integrated approach is illustrated with an example taken from a real EAS instantiation

Aplicabilidad de B-CUBE al sector servicios

Ponencia presentada en el XII Congreso Internacional de Ingeniería de Proyectos celebrado en Zaragoza en el año 2008With the concept of globalization and the delegation of the tasks that major manpower need, the core of the economy of the capitals of the major world powers has derived to the tertiary sector (services sector). In this field to support the competitiveness is not enough, it is necessary continue improvement in order to not be displaced of the market by others. Functional design, widely used successfully in all the engineering fields, has been revealed as a useful tool in the tertiary sector, when it comes to design the companies and establish relations between departments based on functions that they play inside the company. B-Cube is a new approach to functional design through FBS framework. The above mentioned approach purposes a three dimensional scheme that uses definitions as Behaviours concepts. The key of this approach is that a Behaviour is not defined with a word or a taxon, which could cause ambiguity and misinterpretation, but rather defined as a three dimensional vector (X, Y, Z), set by its characteristics and qualities. In this work we present the process to elaborate a functional design of a company of the services sector through the B-Cube model, defended with a practical application.Con el concepto de globalización y la delegación de las tareas que mayor mano de obra requieren, el motor de la economía de las capitales de las mayores potencias mundiales ha derivado al sector terciario, los servicios. En este campo mantener la competitividad no es suficiente sino que es necesario mejorarla para no ser desplazado en el mercado por otros. El diseño funcional, ampliamente utilizado con éxito en todos los campos de la ingeniería, se ha revelado como una herramienta útil en el sector terciario, a la hora de diseñar las empresas y establecer relaciones entre los departamentos en base a las funciones que éstos desempeñan dentro de una empresa. B-Cube es un nuevo enfoque para el diseño funcional a través del marco FBS. Dicho enfoque propone un planteamiento tridimensional que utiliza definiciones a modo de conceptos de los Behaviours. La clave de este planteamiento es que un comportamiento no queda definido por una palabra o taxón, sino que el comportamiento viene definido como un vector tridimensional (X, Y, Z), determinado por sus características y cualidades. En este trabajo se presenta el proceso para elaborar un diseño funcional de una empresa del sector servicios a través del modelo B-Cube, defendido con una aplicación práctica

Functional Modeling in Conceptual Die Design

The use of function has been recognized as an important part of the design process over last two decades, especially at the conceptual design stage, due to its critical role in determining the final product’s functionality. Although there are now some general methodologies dealing with functions or reasoning about functions, virtually no commercial CAD system can support conceptual design process due to their focus on geometrical modeling but not functional modeling. This paper presents a functional modeling approach to guide conceptual die design through functional reasoning steps including functional decomposition, functional supportive synthesis and function-structure mapping. The formed functional model provides a good basis to generate various die structures at the conceptual design stage, because function is a higher level of abstraction than structure, and helps to capture the designer’s intent. The functional modeling process has been implemented in a computerized design environment to expedite the conceptual die design process.Singapore-MIT Alliance (SMA

Towards Integration of CAx Systems and a Multiple-View Product Modeller in Mechanical Design

This paper deals with the development of an integration framework and its implementation for the connexion of CAx systems and multiple-view product modelling. The integration framework is presented regarding its conceptual level and the implementation level is described currently with the connexion of a functional modeller, a multiple-view product modeller, an optimisation module and a CAD system. The integration between the multiple-view product modeller and CATIA V5 based on the STEP standard is described in detail. Finally, the presented works are discussed and future research developments are suggested.

Service integration in distributed control systems: an approach based on fusion of mereologies

International audienceThe objective of the present paper is to provide a methodology where the functional characteristics of a distributed engineering system can be obtained by merging domaindependent knowledge at run-time. We focus on distributed control systems where computing nodes are related to the physical environment in which they operate via sensors/actuators. The knowledge representation is formally expressed with a mereological approach where a structural mereology describes the physical environment and a functional mereology identifies available engineering goals for each computing node. During the design step, a mechanism based on Formal Concept Analysis (FCA) allows to generate the resulting goal mereology. The concept of goal is refined with sub-concepts in the multilevel structure. Because computing nodes depend on each other for goals to be achieved, an agent-based method is proposed to establish dynamically the dependencies among distributed nodes. This method is centered on a fusion mechanism involving the functional mereologies of appropriate nodes. We use an example from an open-channel hydraulic system controlling the water level to motivate and illustrate the model. Although it is limited to the engineering systems, this approach can be reused in related domains where the goal representation can be expressed as a triple including an action, a role and a physical entity

Functional design of mechanical products based on behavior-driven function-environment-structure modeling framework

The relative significance of upstream design activity to downstream design activity is widely recognized, due to its critical role in determining the final product’s functionality. Although there are now some general methodologies dealing with functions or reasoning about functions, virtually no commercial CAD system can support functional design. In functional modeling, a design problem is represented in a hierarchy of functions and the behaviors that realize the functions. This paper presents a functional design methodology based on a behavior-driven function-environment-structure (B-FES) modeling framework to guide functional design through functional reasoning steps including causal behavioral reasoning (CBR) and functional decomposition. The proposed functional design starts from a set of design specifications including functional requirements and design constraints, and results in diverse behavioral schema corresponding to a set of design alternatives. A design example for functional design of a terminal cut-off unit in an automatic assembly system is used to provide a demonstration of the proposed functional design methodology.Singapore-MIT Alliance (SMA

Multiple viewpoint modelling framework enabling integrated product-process design

Nowadays, companies have to cope with numerous constraints at organisational and technical levels in order to improve their competitiveness edges such as productivity, efficiency, and flexibility. Integrated product-process design becomes more and more complex to manage because of increasingly customized products related to various stakeholders and concerns geographically distributed. It is still represents a huge challenge, especially in the early phases of product development process. In such a context, the management of information within integrated product-process design highlights needs in a consistent engineering model that enables product lifecycle management (PLM) integration. The paper presents a novel multiple viewpoint framework called multiple viewpoint assembly oriented, considering product design and assembly process domains in the broader context of concurrent engineering and PLM. The proposed framework describes the consistency, the propagation of information change, and mechanisms of views generation among the product lifecycle stages in order to support assembly oriented design philosophy. A new modelling language called System Modeling Language is used to describe the proposed model from a systems engineering point of view. The implementation of the model in a Web-service called PEGASUS as an application for PLM systems is describe

Interoperability between Cooperative Design Modeller and a CAD System: Software Integration versus Data Exchange

International audienceThe data exchange between Computer-Aided Design (CAD) systems is a crucial issue in concurrent engineering and collaborative design. The paper presents research works and techniques dealing with the interoperability of a Cooperative Design Modeller (CoDeMo), aiming at the integration of product lifecycle knowledge, and a commercial CAD system (CATIA V5). Two kinds of approaches are implemented in the considered case of CAD interoperability for exchanging geometric data, respectively: one is based on a traditional static interface, in which STEP AP203 standard is used; the other is based on a dynamic interface, in which Application Programming Interfaces (API) of the targeted CAD system is adopted. Both approaches should enhance the communication, exchange and sharing of product data between CAD systems for improving concurrent engineering. A comparison between these two approaches is made to show their particular advantages and disadvantages. The development of a translator between the both CAD systems based on each approach has been carried out and evaluated on an assembly case

Fault Diagnosis approach based on a model-based reasoner and a functional designer for a wind turbine. An approach towards self-maintenance

The objective of this on-going research is to develop a design methodology to increase the availability for offshore wind farms, by means of an intelligent maintenance system capable of responding to faults by reconfiguring the system or subsystems, without increasing service visits, complexity, or costs. The idea is to make use of the existing functional redundancies within the system and sub-systems to keep the wind turbine operational, even at a reduced capacity if necessary. Re-configuration is intended to be a built-in capability to be used as a repair strategy, based on these existing functionalities provided by the components. The possible solutions can range from using information from adjacent wind turbines, such as wind speed and direction, to setting up different operational modes, for instance re-wiring, re-connecting, changing parameters or control strategy. The methodology described in this paper is based on qualitative physics and consists of a fault diagnosis system based on a model-based reasoner (MBR), and on a functional redundancy designer (FRD). Both design tools make use of a function-behaviour-state (FBS) model. A design methodology based on the re-configuration concept to achieve self-maintained wind turbines is an interesting and promising approach to reduce stoppage rate, failure events, maintenance visits, and to maintain energy output possibly at reduced rate until the next scheduled maintenance