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A key to shortening the design cycle is to shorten the initial or conceptual design phase. An enabling technology towards this goal is an architecture called the Design Support System (DSS), which is based on the virtual prototype concept. The DSS combines knowledge with hardware and software into a system that is a model for the design process. It produces a virtual prototype of the design and maintains an intelligent design document, which is automatically updated during the design process. A design domain dependent version for automotive design, known as “Automobile Design Support System” (AutoDSS) was developed in the CADTECH Research Lab at the University of Washington.

This paper will deal with an emerging technology in the world of design known as Knowledge-Based Design, or KBE. KBE, also known as Rule-Based Design, provides the design engineer with the ability to develop a true virtual prototype of a product prior to committing to manufacturing. A virtual prototype is a combination of the design rules, or product model, and the vehicle geometry. A virtual prototype has all of the geometric characteristics, or attributes, of the product as well as all of the non-geometric attributes such as materials, mass properties, stress and deflection characteristics, etc. KBE allows the development of computer-based tools for the design engineer that extends beyond the capability of current CAD and parametric tools. The early stages of automobile design differs from the traditional method used in aircraft or marine design where there is a well-defined conceptual, or early stage, design phase.

The objective of the development of the aerodynamic drag predictive tool CDaero was for use as a module for the Automobile Design Support System (AutoDSS). CDaero is an empirically based drag coefficient predictive tool based initially on the MIRA (Motor Industry Research Association) algorithm. The development philosophy was to be able to predict the aerodynamic drag coefficient of an automobile with knowledge of the features of the surface geometry control curves. These are the curves that control the 3-dimensional geometry as seen in the profile, plan and front and rear views. CDaero has been developed in a computing environment using the equation solver TKSolver™. Fifty-one input feature values are first determined from the automobile geometry and then entered into the program. CDaero models the drag coefficient with thirteen different components covering the basic body, as well as additional components such as the wheels, mud flaps, etc.

A Knowledge Based Engineering (KBE) tool called ICAD, is being used to develop a design tool for automobile conceptual design. The design tool, known as AutoDSS, is based on an environment architecture which is known as a Design Support System (DSS). The Design Support System creates a virtual prototype of the automobile that includes all of the major assemblies including the exterior body shell, chassis, passengers, power train and running gear. The AutoDSS includes both a geometrical and non-geometrical description of the automobile. The components of the AutoDSS comprise a knowledge base, a high level graphics design environment, a feature based geometry modeler and a synthesis model.

The purpose of this paper will be to describe how design has been integrated into the Mechanical Engineering curriculum at the University of Washington. The design education program includes participation in three NSF and ARPA sponsored engineering education coalitions or partnerships, including ECSEL, MEEP and TIDEE. This effort has resulted in a new perspective on how design engineering education should be integrated into the Mechanical Engineering curriculum at the freshman, junior and senior levels. Then a special version of the Mechanical Engineering senior level capstone design class based on the “Focus Based” paradigm will be presented. Finally, recent developments in the Mechanical Engineering curriculum structure and their effect on the design content will be described.