Integration of design tools and knowledge capture into a CAD system: a case study

onceptual design phase is partially supported by product lifecycle management/computer-aided design (PLM/CAD) systems causing discontinuity of the design information flow: customer needs — functional requirements — key characteristics — design parameters (DPs) — geometric DPs. Aiming to address this issue, it is proposed a knowledge-based approach is proposed to integrate quality function deployment, failure mode and effects analysis, and axiomatic design into a commercial PLM/CAD system. A case study, main subject of this article, was carried out to validate the proposed process, to evaluate, by a pilot development, how the commercial PLM/CAD modules and application programming interface could support the information flow, and based on the pilot scheme results to propose a full development framework

A process model in platform independent and neutral formal representation for design engineering automation

An engineering design process as part of product development (PD) needs to satisfy ever-changing customer demands by striking a balance between time, cost and quality. In order to achieve a faster lead-time, improved quality and reduced PD costs for increased profits, automation methods have been developed with the help of virtual engineering. There are various methods of achieving Design Engineering Automation (DEA) with Computer-Aided (CAx) tools such as CAD/CAE/CAM, Product Lifecycle Management (PLM) and Knowledge Based Engineering (KBE). For example, Computer Aided Design (CAD) tools enable Geometry Automation (GA), PLM systems allow for sharing and exchange of product knowledge throughout the PD lifecycle. Traditional automation methods are specific to individual products and are hard-coded and bound by the proprietary tool format. Also, existing CAx tools and PLM systems offer bespoke islands of automation as compared to KBE. KBE as a design method incorporates complete design intent by including re-usable geometric, non-geometric product knowledge as well as engineering process knowledge for DEA including various processes such as mechanical design, analysis and manufacturing. It has been recognised, through an extensive literature review, that a research gap exists in the form of a generic and structured method of knowledge modelling, both informal and formal modelling, of mechanical design process with manufacturing knowledge (DFM/DFA) as part of model based systems engineering (MBSE) for DEA with a KBE approach. There is a lack of a structured technique for knowledge modelling, which can provide a standardised method to use platform independent and neutral formal standards for DEA with generative modelling for mechanical product design process and DFM with preserved semantics. The neutral formal representation through computer or machine understandable format provides open standard usage. This thesis provides a contribution to knowledge by addressing this gap in two-steps: • In the first step, a coherent process model, GPM-DEA is developed as part of MBSE which can be used for modelling of mechanical design with manufacturing knowledge utilising hybrid approach, based on strengths of existing modelling standards such as IDEF0, UML, SysML and addition of constructs as per author’s Metamodel. The structured process model is highly granular with complex interdependencies such as activities, object, function, rule association and includes the effect of the process model on the product at both component and geometric attributes. • In the second step, a method is provided to map the schema of the process model to equivalent platform independent and neutral formal standards using OWL/SWRL ontology for system development using Protégé tool, enabling machine interpretability with semantic clarity for DEA with generative modelling by building queries and reasoning on set of generic SWRL functions developed by the author. Model development has been performed with the aid of literature analysis and pilot use-cases. Experimental verification with test use-cases has confirmed the reasoning and querying capability on formal axioms in generating accurate results. Some of the other key strengths are that knowledgebase is generic, scalable and extensible, hence provides re-usability and wider design space exploration. The generative modelling capability allows the model to generate activities and objects based on functional requirements of the mechanical design process with DFM/DFA and rules based on logic. With the help of application programming interface, a platform specific DEA system such as a KBE tool or a CAD tool enabling GA and a web page incorporating engineering knowledge for decision support can consume relevant part of the knowledgebase

Exchange of knowledge in customized product development processes

If Customized Product Development is perceived as developing products that fulfill the customers individual requirements and in parallel reflect production constraints, such as manufacturing capabilities, a direct demand can be derived for solutions to adapt a given design easy and fast to new requirements based upon the companies production knowledge - at best in an automated way. The latter is usually covered by Knowledge Based Engineering systems. KBE systems are capable to automate repetitive engineering tasks, such as the automated calculation of ship structural design. However, while the efficiency of implemented KBE projects is non controversial, the development or modification of an existing KBE solution usually requires substantial investments due to knowledge acquisition, codification and software implementation. In addition most solutions are still case based and not grounded in structural frameworks. Knowledge is often written in a proprietary language; rules and algorithms are not compatible with other KBE-frameworks and are usually not on a level that is comprehensible for the engineers or domain experts. While this may not be crucial for long development cycles, it may become a hurdle in terms of Customized Product Development with its short cycles. In other words, future KBE must support an incorporation of knowledge from different domains and business units. Thus the objective of the paper is to explain the need for a change in collaborative knowledge sharing and re-use in context of KBE. Based upon, the constraints for a KBE related interchange format are drafted. A three layered approach is proposed in order to adequately represent and exchange KBE knowledge. Each layer addresses different levels of abstraction: an upper layer describing just the core knowledge at a glance, a middle layer in order to codify the knowledge on abstract level, but with purpose of software development and a base layer covering the software code itself. Utilizing an independent format for management of KBE knowledge, the users of CAx systems are able to exchange codified knowledge and gain the rationale behind. Hence the full paper attempts to deliver a substantial contribution for the development of systems, which are capable to easily adapt a given design to upcoming user-requirements, while facing the production challenges

Towards an ontology-based platform-independent framework for developing KBE systems in the aerospace industry

Aerospace engineering is considered to be one of the most complex and advanced branches of engineering. The use of knowledge based engineering (KBE) technologies has played a major role in automating routine design activities in view of supporting the cost-effective and timely development of a product. However, technologies employed within KBE systems are usually platform-specific. The nature of these platform-specific models has significantly limited knowledge abstraction and reusability in KBE systems. This research paper presents a novel approach that illustrates the use of platform-independent knowledge models for the development of KBE systems in the aerospace industry. The use of semantic technologies through the definition of generic-purposed ontologies has been employed to support the notion of independent knowledge models that strengthens knowledge reusability in KBE systems. This approach has been validated qualitatively through experts’ opinion and its benefit realised in the abstraction, reusability and maintainability of KBE systems

Practitioner requirements for integrated Knowledge-Based Engineering in Product Lifecycle Management.

The effective management of knowledge as capital is considered essential to the success of engineering product/service systems. As Knowledge Management (KM) and Product Lifecycle Management (PLM) practice gain industrial adoption, the question of functional overlaps between both the approaches becomes evident. This article explores the interoperability between PLM and Knowledge-Based Engineering (KBE) as a strategy for engineering KM. The opinion of key KBE/PLM practitioners are systematically captured and analysed. A set of ranked business functionalities to be fulfiled by the KBE/PLM systems integration is elicited. The article provides insights for the researchers and the practitioners playing both the user and development roles on the future needs for knowledge systems based on PLM

Nuevo enfoque en el diseño inteligente de implantes craneales personalizados a través de KBE

Ponencia presentada en el XI Congreso Internacional de Ingeniería de Proyectos celebrado en Lugo en el año 2007The need of adapting intelligent design to the medical domain in order to develop applications adjusted to the needs of patients has driven the creation of tools capable of combining product customization with cost reduction, integrating all the knowledge involved in the process in an organized manner. The present study investigates a new approach in the application of Knowledge-Based Engineering (KBE) to the automation of the implant design process. Furthermore, the customization of implants is achieved, adapting to the anatomy of the patient and attaining structural, functional and aesthetic biocompatibility. A KBE based tool, capable of performing customized design of cranial implants, is defined. To that avail, CATIA® software -which incorporates KBE and CAD (Computer Aided Design) modules - is used. The developed program performs an automatic modelling of a volume that covers an existing skull defect, based on the knowledge gathered and the restrictions indicated by the user. As an added option, the volume generated may be machined using RP (Rapid Prototyping) techniquesLa necesidad de adaptar el diseño inteligente al ámbito médico para desarrollar aplicaciones ajustadas a las características del paciente impulsa la creación de herramientas capaces de aunar la personalización del producto con la reducción de costes, integrando todo el conocimiento del proceso de manera organizada. Este estudio investiga un nuevo enfoque para la aplicación de la Ingeniería Basada en el Conocimiento (KBE, Knowledge-Based Engineering) en la automatización del proceso de diseño de implantes. Además, se logra la personalización de dichos implantes, adaptándose a la anatomía del paciente y consiguiendo una biocompatibilidad estructural, funcional y estética. Se define una herramienta basada en KBE capaz de realizar un diseño personalizado de implantes para la zona craneal. Para tal fin, se utiliza la herramienta informática CATIA®, donde están incluidos como módulos los sistemas KBE y CAD (Computer-Aided Design). El programa creado realiza un modelado automático de un volumen para cubrir un defecto craneal existente a partir del conocimiento recogido y de las restricciones indicadas por el usuario. Se añade la posibilidad de que el volumen generado sea mecanizado mediante técnicas de prototipado rápido (RP, Rapid Prototyping)

Information Technology of Generalized Model Creation of Complex Technical Objects

The paper introduces a knowledge representation framework for design and geometrical modelling of complex technical objects such as ships, aircrafts, cars, etc. The design process cannot be fully automated yet because of a lot of technical and economical factors that influence the decisions during that process. In order to make the process more efficient, a knowledge modelling framework is suggested. The basic principles of conceptual knowledge modelling and data exchange framework are presented. A practical use case of aircraft ramp modelling is provided

Application of knowledge based engineering principles to intelligent automation systems

The automation of engineering processes provides many benefits over manual methods including significant cost and scheduling reduction as well as intangible advantages of greater consistency based on agreed methods, standardisation and simplification of complex problems and knowledge retention. Knowledge Based Engineering (KBE) and Design Automation (DA) are two sets of methodologies and technologies for automating engineering processes through software. KBE refers to the structured capture, modelling and deployment of engineering knowledge in high level intelligent systems that provide a wide scope of automation capability. KBE system development is supported by numerous mature methodologies that cover all aspects of the development process including: problem identification and feasibility studies, knowledge capture and modelling, and system design, development and deployment. Conversely, DA is the process of developing automated solutions to specific, well defined engineering tasks. The DA approach is characterised by agile software development methods, producing lower level systems that are intentionally limited in scope. DA-type solutions are more commonly adopted by industry than KBE applications due to shorter development schedules, lower cost and less complex development processes. However, DA application development is not as well supported by theoretical frameworks, and consequently, development processes can be unstructured and best practices not observed. The research presented in this thesis is divided into two key areas. Firstly, a methodology for automating engineering processes is proposed, with the aim of improving the accessibility of mature KBE methods to a broader industrial base. This methodology supports development of automation applications ranging in complexity from high level KBE systems to lower level DA applications. A complexity editing mechanism is introduced that relates detailed processes of KBE methodologies to a set of characteristics that can be exhibited by automated solutions. Depending on individual application requirements, complexity of automated solutions can lowered by deselecting one or more of these characteristics, omitting associated high-level processes from the development methodology. At the lowest level of complexity, the methodology provides a structured process for producing DA applications that incorporates principles of mature KBE methodologies. The second part of this research uses the proposed automation methodology to develop a system to automate the layout design of aircraft electrical harnesses. Increasing complexity of aircraft electrical systems has an associated increase in the number and size of electrical harnesses required to connect subsystems throughout the airframe. Current practices for layout design are highly manual, with many governing rules and best practices. The automation of this process will provide a significant reduction in low level, repetitive, manual work. The resulting automated routing tool implements path-finding techniques from computer game artificial intelligence and microprocessor design domains, together with new methods for incorporating the numerous design rules governing harness placement. The system was tested with a complex industrial test case, and was found to provide harness solutions in a fraction of the time and with comparable quality as equivalent manual design processes. The repeatability of the automated process can also minimise scheduling impacts caused by late design changes

Using Axiomatic Design for the Development of Product Configuration Systems

In order to meet a wide range of customer requirements in product development, a high degree of individualization is necessary today, which can be achieved with product configuration systems. Knowledge-based CAD models are a useful tool for implementing such configurators, but they are significantly more complex to develop than conventional parametric CAD models. To master this complexity, this article examines the use of the axiomatic design approach for the development of a configurator for a skip loader. In combination with the parameter space matrix, an application-oriented methodology is derived which is suitable for the development of similar configuration systems

Interactive Geometric Configuration Using Sketch-Based CAD Models

Knowledge-based geometry models reduce variant design to the input of parameter values. Especially knowledge-based CAD models that incorporate geometrical data and implemented explicit knowledge offer additional possibilities. One is interactive drag-and-drop control of geometric features. This poses new requirements for the setup of CAD models as each geometric constraint, dimension and 3D feature contributes to the variability of the model. In this paper, the authors give methodological guidance to such modeling tasks by extending the CommonKADS approach with a correlation model for CAD model entities. The guidelines are visualized for the creation of an interactive, configurable steel construction model