The Multimedia Finite Element Modeling and Analysis Tutor

Article excerpt

ABSTRACT

This prototype interactive software system can help teach upper level undergraduate and graduate students in mechanical engineering fundamental concepts and offer guidelines for finite element modeling and analysis (herein referred to as FEA). In lieu of a mathematical treatment of the subject commonly found in textbooks, this FEA tutoring system employs rich animations for conveying highlyvisual concepts and offers the user a set of experiential modules for exploratory learning. The system has been developed initially for the domain of linear structural analysis, but it can be expanded to include other engineering analysis domains, such as vibration, heat transfer, and nonlinear finite element analysis. Initial formative testing of the tutor on junior mechanical engineering students indicates that a 45-minute session with the tutor was at least as effective as a one-hour introductory lecture by an FEA expel.

INTRODUCTION

The process of designing and manufacturing products has traditionally been fractured into three broad groups. One group consists of designers who are knowledgeable in drafting, CAD, design guidelines, standard components and modules, existing product designs, and "back-of-the-envelope" engineering analysis skills. Toolmakers fit into another category, being knowledgeable about designing the molds or tooling needed to create the parts as well as the speed and cost of production using such a mold. In the third group are specialized engineering analysts knowledgeable in sophisticated computer-based analysis concepts and techniques, such as finite element analysis (FEA), that can be used to simulate the behavior of real-world products and manufacturing processes.

This compartmentalization of knowledge and practices results in a time-consuming, costly iterative process that places U.S. manufacturing at a competitive disadvantage. More often than not, computer-based analysis of designs is simply not carried out early in the design process. This occurs despite the fact that simulation techniques, such as FEA, are mature technologies with well-established comprehensive commercial software products currently on the market. Designers simply do not have the time to "throw their proposed design concepts over the wall to the analysis group" and wait for simulation results. Engineering analysts often fail to fully grasp time constraints driven by brief market windows of opportunity that design engineers constantly face. Consequently, an engineering analyst will tend to devote a large amount of time and computational resources developing highly complex finite element models when less accurate, rapid-feedback analysis results would suffice. The net result is that FEA usually takes place after hard tooling has been committed or after the product has failed in service in an effort to understand why the product failed.

Despite the fact that FEA has become the world's most widely used numerical technique for predicting the behavior of complex physical systems, it is not typically taught in the undergraduate engineering curriculum. There are two principle reasons for this deficiency. The first is that the introduction of new material into the curriculum by modifying existing courses or by creating new courses typically requires the removal of other material from the curriculum. Often this material is deemed essential by the faculty and ABET. Also, while FEA is taught at the graduate level in mechanical, civil, and aerospace engineering departments, graduate-level FEA courses are designed to teach the underlying mathematical theory (Ritz Variational Method, Method of Weighted Residuals, etc.), numerical techniques, and to a lesser extent computer software implementations. Such courses prepare students to use FEA in research projects or to develop FEA algorithms and software codes. However, these courses are not designed to teach fundamental modeling principles and guidelines that design engineers and industry need to effectively use FEA to address realworld design and manufacturing problems. …