Concurrent Engineering Design Research Articles

Employing the Concurrent Design Philosophy in Developing an Engineering Design Science Programme

North American undergraduate mechanical engineering design education has failed to meet the needs of industry in educating students in effective design philosophies typified by the concurrent engineering design philosophy. Current programmes emphasize traditional engineering analysis courses, leaving little room for truly educating the students in the fundamentals of mechanical engineering design. This paper uses the concurrent engineering design paradigm to design a programme for the education of students in mechanical engineering design. The basics of concurrent engineering design are outlined, the failings of typical design education stated, and an exploration of the required features of a new design curriculum presented.

CONCENSUS: multi-party negotiation support for conflict resolution in concurrent engineering design

Advances in telematics have led many manufacturing companies in particular to explore the adoption of groupware technology to improve communication between team members. However, complex activities such as conflict resolution are still predominantly facilitated through face-to-face negotiation meetings. Intelligent software agents technology is being applied to support computer-mediated conflict resolution activities, such as information search and retrieval, recording negotiation process history and task allocation – whilst the creative negotiation activities such as generating new solutions, preventing and detecting conflicts are still left to the human experts. This paper describes the development of a framework for the support of multi-party negotiation for multi-agent systems, which will be introduced through a general overview of the requirements of multi-agent negotiation. Finally, the current architecture of the developed prototype for a CONCurrent Engineering Negotiation SUpport System (CONCENSUS) is presented.

Concurrent engineering design using intelligent agents

Description d'un logiciel d'enseignement assiste par ordinateur, ayant pour but d'apprendre aux eleves ingenieurs a travailler dans un environnement concurrentiel

World Wide Web integration of manufacturing process simulations

Manufacturing process simulations typically execute on a single platform, and are language and operating system-specific. With the growth of agile enterprises, however, the need is emerging to perform manufacturing process simulations in a distributed fashion from remote locations. In addition, individual businesses are becoming more decentralized, with geographically dispersed manufacturing and design teams. For effective concurrent engineering, product and process design teams that are in different locations need direct access to simulation tools. In addition, small- and medium-sized businesses cannot afford high-end computers and software for computationally intensive process simulations. Hence, these businesses could greatly benefit from easy access to high-end systems located remotely. The World Wide Web provides an excellent medium for remote collaboration and computing. Manufacturing process simulations can be deployed over the World Wide Web for remote access to simulations. This paper discusses the different methods for integrating manufacturing process simulations with the Web. An implementation of a Web-based metalworking process simulation with defect prediction is also presented. © 1997 John Wiley & Sons, Ltd.

A simple visualization tool to support concurrent engineering design

Due to the nature of the die casting process, the part geometry restricts the die design significantly and hence affects the quality of the part. However, as is often the case in other manufacturing processes, the manufacturability of die castings is not considered until the design has been nearly completed and detailed. Primarily, this is due to the limited capability of current Computer-Aided Engineering (CAE) tools to support design evaluation, especially during preliminary design. In this paper, we present a new volume-based geometric reasoning and visualization approach to support this task. This system is very efficient in terms of computation time and can evaluate the whole range of designs regardless of their shape complexity. In addition, it is very simple-to-use and the results are self-evident. The current focus is on thermal- and flow-related problems in die casting. Our approach, however, is general and can be applied to other manufacturing processes.

Design for Accuracy and Repeatability for Robots Using Taguchi Methods

In this paper, we apply Taguchi Methods in the framework of concurrent engineering design for robot-based manufacturing sys tems to obtain higher accuracy and repeatability for robot end-effectors. It is well known that the configurations of robot end-effectors in workspace will affect the accuracy and repeatability Taguchi Methods are employed to find the configuration and location within which the accuracy and repeatability are the best. The optimal position with higher accuracy and repeatability is determined by using the signal-to- noise ratios (S/N ratios), which are defined according to the "smaller-the-better" characteristics of Taguchi Methods to measure the accu racy and repeatability The results match well with the theoretical analysis of the repeatability and accuracy of the end-effector based on the kinematic relationship. In addition, we also study the random and systematic errors due to joint uncertainties and examine their effects on the accuracy and repeatability. The analysis using S/N ratios yields results that are consistent with expectation. The results demonstrate that Taguchi Methods and S/N ratios are very useful tools in design for accuracy and repeatability of robotic end-effectors. The sensitivity and consistency of accuracy with respect to the tolerance of joint angles are represented by 3D surfaces. The tolerance design is per formed, using the sensitivity analysis, to satisfy requirements stipulated by design criteria One of the significant results of consistency analysis is the "threshold" value of tolerance for concurrent engineering design considerations. Simulation results show that the consistency of accuracy and repeatability will be increased dramatically once the tolerance is below such a threshold Both sensitivity and consistency analysis are shown to be important in tolerance design for achieving the desired accuracy and repeatability and for enhancing quality.

Concurrent engineering in design-build projects

The design and build procurement route has witnessed significant growth in the UK construction industry over the last ten years. It is now being used for both private and public sector projects of varying complexity. There are several advantages associated with this method of construction procurement including shortening of lead times, involvement of the contractor in the design process, greater price certainty, improved communication and reduced construction time amongst others. Conversely, there are also a number of disadvantages ascribed to the design and build method of procurement. Some of these include reduced design quality, inhibition of changes by clients, and high tendering costs. A new process model is proposed to address many of the procurement route's present shortcomings. In particular, the model facilitates concurrent project development in the design and build process through the integration of all project participants into a multi-functional matrix team capable of resolving potential ‘downstream’ problems early in the project life-cycle, and the provision of a formal mechanism for the improved abstraction of client requirements based on design function deployment (DFD)- a concurrent engineering design system.

Evaluation of Failure Diagnosis in Conceptual Design of Mechanical Systems

This paper discuses a methodology for improving quality and reducing life cycle costs of mechanical systems. The principal concept is that a system can be designed, in the conceptual stages, to be easier to diagnose for failures. To perform this, functional decomposition and form-to-function mapping are utilized to demonstrate the relation of design to diagnosis and for diagnosis itself. Four diagnosability metrics are developed and four hypothetical conceptual designs are evaluated for diagnosability and compared. An example is presented wherein three conceptual designs for a toolhead positioning system are evaluated for diagnosability at two levels of abstraction and the results compared. The area of design for diagnosis offers promise in improving system quality and reducing life cycle cost; research is continuing to refine and integrate the procedures with other aspects of the concurrent engineering design process.

Intelligent electronic mock-up for concurrent design

As part of a European collaborative research project, which aims at identifying the advanced communications requirements to support concurrent engineering design, an Intelligent Mismatch Control System (IMCS) was developed to automatically identify mismatches of geometric nature during the integration phase of a distributed collaborative design process. The IMCS is acknowledge-based software module which uses a commercial CAD system (Parasolid), as the core geometric modeller, to detect any potential geometric irregularities in the design and suggest a modification proposal to modify them. The system was recently demonstrated across a European broadband telecommunications network which linked four sites: Aerospatiale-Cannes (France); ONERA-Paris (France); BT Labs (UK) and Cranfield University (UK). The IMCS was invoked remotely (from Paris) using a mullet-agent approach. The demonstration was attended by a wide cross-section of potential users from the European Aerospace industry, and initial feedbacks suggest that the IMCS was well received as a powerful tool that will have an important contribution to the success of distributed design using advanced communication systems.

Direct interface integration of CAD and CAM software — a milling application

Computer Integrated Manufacturing (CIM) is considered to be a strategy for planning, implementing, and integrating many functions in a manufacturing organization. A concurrent engineering design environment encourages multi-disciplinary communication of design ideas very early in the design cycle. A contemporary approach to realize the benefits of concurrent engineering design uses automated computer systems and a plethora of computer aided engineering tools. Methods are needed to integrate these tools, as most of them are stand-alone software tools that do not communicate to each other effectively. This paper presents a methodology that can integrate an advanced CAD software and a process planning software. A milling application example is used to demonstrate how the primary machining parameters can be calculated and directly imported to the CAD software, thus creating a seamless preparation of the NC part program.

Integration of CAD and FEA for Concurrent Engineering Design of Sheet Stamping

The tedious process of building an input model and of manual communication between CAD and Finite Element Analysis (FEA) significantly restricts the designers from using FEA, particularly in preliminary design. Most of the previous works concentrate on expediting this process by interfacing CAD and FEA. This paper propose full integration of FEA simulation code within a CAD system, thus several problems are avoided. The section-based FEA is used as better suited to early design. It requires, comparing to the 3-D FEA, development of additional CAD functions to extract appropriate sections from the CAD model. The proposed integrated system allows for rapid use of the FEA and unifies the design environment to avoid inconsistency. It provides a mechanism to specify the part orientation relative to the punch traveling direction to support tipping. It also extracts the geometrical data of a specified section to automatically build and store a FEA input model. The numerical simulation of the process can be then performed without exiting the CAD system. Both existing as well as newly developed CAD functions, needed for the proposed integration system, are presented. The feasibility and advantages of such integration is demonstrated on the developed prototype system.

Automated design-to-cost: integrating costing into the design decision

While the concepts of design for manufacturability and concurrent engineering have made significant advances in integrating the design function with other areas in the firm, there are still major gaps in timely and accurate costing information available to designers. Our research develops a conceptual model and working prototype of a new application for blending product design and cost accounting, that of automated design-to-cost. The purpose of the application is to provide rapid and dynamic feedback during the design process regarding estimated final product cost of a new part design. The system first calculates the cost of a new part design directly from existing computer-aided design, accounting, and other computer-integrated manufacturing databases. It then finds and displays, along with their costs, all existing parts that are similar or ‘near’ to the proposed part. The model developed was successfully implemented as a prototype. It is able to integrate and process information from the diverse databases of feature-based modelling computer-aided design, group technology classification, computer-aided process planning and activity-based costing. Copyright

A representation formalism for feature-based design

Feature-based design is regarded as a promising approach for design. However, it lacks a formal methodology for system development and operation. One repercussion of this is that feature-based design is, at present, implemented in a relatively ad hoc manner. This paper aims to address this deficiency by establishing a domain-independent representation formalism for feature-based design. The proposed representation formalism consists of a feature algebra, a design algorithm and a system architecture/development methodology. The proposed representation formalism aims to make it possible to develop a feature-based design system for a specific design domain in a structured way. In addition, by using the representation formalism as a research framework, other issues of feature-based design can be addressed. The research in this paper contributes to several aspects of design research, especially to the area of integrating concurrent engineering and feature-based design.

Concurrent engineering design using interval methods

Modern design practice has displaced serial approaches in favour of concurrent engineering design (CED), which takes several fields simultaneously into consideration, using interaction and iteration to proceed towards generally acceptable solutions. Concurrent design is very often based upon a mathematical model, which not only defines the properties and capabilities of a product, but also economic and production aspects, such as costs, tooling, machine loading and scheduling, and leads to some ‘optimum’ solution satisfying all requirements as closely as possible. This scenario does not reflect actual design activity. Each team member usually has a set of approximate requirements, which can be expressed as a range of admissible values of the design parameters. The aim is to resolve these demands, and determine a set of consistent parameter ranges which then define the design space. Iteration on the implied design alternatives leads to a final solution which is both ‘optimal’ and acceptable. A methodology which is suitable for this purpose is a mathematical model based on interval arithmetic or interval analysis. The intervals for a set of design parameters form a vector which physically defines a multi-dimensional hypercube; the design problem is then studied by a procedures termed hypercube analysis.

Concurrent Engineering Design Using Interval Methods

Modern design practice has displaced serial approaches in favour of concurrent engineering design (CED), which takes several fields simultaneously into consideration, using interaction and iteration to proceed towards generally acceptable solutions. Concurrent design is very often based upon a mathematical model, which not only defines the properties and capabilities of a product, but also economic and production aspects, such as costs, tooling, machine loading and scheduling, and leads to some ‘optimum’ solution satisfying all requirements as closely as possible. This scenario does not reflect actual design activity. Each team member usually has a set of approximate requirements, which can be expressed as a range of admissible values of the design parameters. The aim is to resolve these demands, and determine a set of consistent parameter ranges which then define the design space. Iteration on the implied design alternatives leads to a final solution which is both ‘optimal’ and acceptable. A methodology which is suitable for this purpose is a mathematical model based on interval arithmetic or interval analysis. The intervals for a set of design parameters form a vector which physically defines a multi‐dimensional hypercube; the design problem is then studied by a procedures termed hypercube analysis.

An attribute-space representation and algorithm for concurrent engineering

AbstractThis paper presents a novel formulation of the configuration-design problem that achieves the benefits of the concurrent engineering (CE) design paradigm. In CE, all design concerns (manufacturability, testability, etc.) are applied to an evolving design throughout the design cycle. CE identifies conflicts early on, avoids costly redesign, and leads to better products. Our formulation is based on a distributed dynamic interval constraint-satisfaction problem (DDICSP) model. Persistent catalog agents map onto DDICSP variables and constraint agents map onto DDICSP constraints. These agents use a set of operations and heuristics to navigate the design space to eliminate sets of designs until a solution is found. Experimental results show that an architecture where each catalog agent resides on a separate computer has performance advantages over nondistributed approaches.

Negotiation in a knowledge‐based concurrent engineering design environment

Abstract: Computational support for concurrent engineering design presents a number of issues in the design of knowledge‐based systems. A fundamental concern is the need to provide the life‐cycle perspective in recommending design alternatives. It is argued that such a complex knowledge‐based system should be distributed, due to the inherent problems with large knowledge bases and the maintenance of consistency. Inconsistent local views of a problem and different priorities on design issues are expected between different knowledge‐based design perspectives. These inconsistencies and different priorities will lead inherently to conflict which has to be resolved. This paper addresses the issues and key variables in conflict resolution and presents a strategy that can be applied for managing the conflict resolution process. We propose negotiation as the method of analysing a conflict situation, applying an appropriate conflict resolution strategy and monitoring its performance. We present an overview of the nature of conflict and some conflict resolution strategies, and see in what situations certain strategies are appropriate.

A system for design and concurrent engineering under imprecision

This paper proposes an approach to handling imprecision in design and concurrent engineering systems by using interval analysis and constraint networks. By allowing design parameters to be specified with intervals rather than exact points, this approach permits designers to iteratively transform vague conceptual designs into detailed final designs. When a designer changes a variable's interval or assigns a value, the results are propagated through constraints and the resulting feasible interval for all other dependent variables is pruned. The interval constraint network approach described in this paper extends previous work by allowing the representation of and reasoning about complex constraints involving conditions, conjunctions and disjunctions, as well as both symbolic and numeric variables. Many concurrent engineering constraints cannot be modeled without this sort of representational flexibility. A prototype of this approach has been implemented in a system called SPARK-IP. The operation of SPARK-IP is demonstrated through a concurrent engineering design problem involving printed wiring boards.

Automated design for concurrent engineering

Rather than creating a single design and passing it among critiquing agents, Automated Configuration-Design Service (ACDS) generates the entire set of feasible designs at the start of the design process, and narrows it to yield a final design. >

An Expert System for Concurrent Product and Process Design of Mechanical Parts

A new approach for concurrent product and process design of mechanical parts is presented in this paper. This approach enables designers to ensure that the product will be manufactured with the existing manufacturing facility at high quality and lowest cost. It is composed of an integrated expert and CAD (computer aided design) system that meets the requirements for accomplishing the concept of design for manufacturability or concurrent engineering. The system is based mainly on three tasks: firstly, developing a technique for automated feature recognition from the database of a solid modeller; secondly, interfacing the expert system tool-kit with the solid modelling system; finally, building an expert system that contains extensive information about both manufacturing facilities and product features. The expert system provides feedback about manufacturing concerns such as process limits or design inconsistencies. This work is part of the present extended research plan for developing a generic system suitable for various manufacturing practices based on design for manufacturability strategy.