Showing papers by "Barry O'Sullivan published in 1999"

Using Constraint Programming to Simplify the Task of Specifying DFX Guidelines

Abstract: Increasingly, it is being realised that success in manufacturing requires integration between the various phases of the product life cycle. One of the key aspects of this integration is that, during the design of an artifact, due consideration should be given to facilitating the down-stream phases of the life-cycle. This is frequently known as “Design for X” (or DFX), where the X ranges over such issues as manufacturability, servicability and so on. Vendors of leading CAD software have started to incorporate DFX features into their packages. In addition, vendors have discovered from customer feedback that engineering companies require flexibility as well as functionality: companies which use CAD packages want to specify their own DFX guidelines as well as, or even instead of, relying on standard DFX guidelines supplied by the CAD vendors. If engineers from user companies are to augment CAD packages with companyspecific guidelines, it is important that a language be provided which simplifies this task as much as possible. We are developing a language for this purpose, based on the computational paradigm of constraints. The language, called Galileo6, is intended to be generic in two senses: it can be used to encode guidelines from any product domain and guidelines expressed in it can be applied to designs encoded in a variety of CAD formats. In this paper, we report on an ESPRIT-funded project in which we are integrating the Galileo6 language with an electronics design CAD package called Visula. We describe some aspects of the integration and show the functionality of the system. We report on the experiences of one of the user companies in the ESPRIT consortium, and conclude by discussing our findings. ∗The work reported here was funded by the European Commission under ESPRIT project number 20501, with acronym CEDAS

A new technology for enabling computer-aided EMC analysis

Abstract: The demand for CAD tools which can support integrated product development has grown. Generally, modern CAD systems have associated tools for performing various types of analysis on the CAD representation of a product design. While many CAD vendors distribute electromagnetic compatibility (EMC) analysis systems, many of these systems do not offer user companies sufficient flexibility to define company specific design guidelines. A new technology for enabling computer-aided EMC analysis is presented. Indeed the technology can be used to express any guideline that should be obeyed during design. This technology is more expressive and more flexible than systems currently available on the market. The technology is based on a constraint-based programming language and an associated compilation environment that generates CAD-compatible advice generation modules. While standard EMC rule-sets can be provided with the system, a user-company can incorporate company specific EMC and design guidelines into these rule-sets to develop fully customised design adviser modules for use with their CAD systems. This paper presents a detailed discussion of the technology, illustrating its use with a number of typical EMC and design guidelines used in the printed-circuit board (PCB) industry.

Knowledge processing for timely decision making in Design For X

Abstract: Design For X (DFX) focuses on the optimisation of the product properties from the perspective of the product life-cycle. The product life-cycle comprises phases such as part manufacturing, assembly and service. An important aspect in DFX is the issue of timeliness. In order to achieve an efficient design process it is important that designers consider the right life-cycle demands at the right time during design. This paper proposes the concept of a Design Agenda to meet this goal. The Design Agenda confronts the designer with issues to be considered from a life-cycle (DFX) perspective. The knowledge involved in generating a Design Agenda is identified and structured. In addition, a constraint-based reasoning approach to knowledge processing is proposed that supports the management of the Design Agenda.