Taking Cad Integration To The Next Level

A year ago “Using 3D CAD as a tool to integrate topics across the curriculum” was presented at this forum. That paper discussed the ambitious goal of integrating a 3D CAD tool, primarily IronCADTM , across the curriculum. Integration is continuing, beginning in the freshman year, through the undergraduate program, and into the graduate program. The major challenge presented in the reference paper was to encourage both students and faculty to take the first step to utilize the software in their classes and class work, thereby leveraging the advantages of this powerful and highly visual CAD system. Subsequently, the intent was to encourage widespread use of solid modeling, not only in CAD-based classes requiring creation of technical geometry and/or engineering drawings, but also in other technical classes, non-technical classes or any exercises, requiring tools for geometry, display, animation, and/or web content creation. Based on the initial 4-year plan, ultimate success will be indicated when solid modeling use among faculty and students becomes as ubiquitous as spreadsheet use is now. This paper constitutes a follow-up report on the continuation of that initial effort and documents examples of both faculty and student integration of modeling-based projects. A faculty survey performed in Fall 2001 indicated strong Purdue University MET faculty support for the direction previously set forth. Of the six CAD software packages surveyed, two packages indicated an increased future utilization, while four indicated decreased future utilization in Purdue University’s MET department. Examples of this 3D CAD integration using solid modeling will include formal and informal class projects and extracurricular activities, as well as the development and final outputs of a number of open-ended design projects spanning from freshman through graduate level. Other examples include the modeling and animated operation of mechanical assemblies such as an arbor press and a rack mounted stereo system; an independent study team project to develop a BattlebotTM robot; experimental mechanics team projects to develop indestructible football goal posts and to rapidly design, analyze, and visualize stresses in a combined stress experiment; industrial internship projects; a project involving metalcasting design optimization involving metal stream shrouding in pouring large high-alloy steel castings. Two additional courses have had students utilize solid modeling as a result of this effort and these efforts are summarized. Introduction: The process of CAD integration was begun at the freshman level with a second semester course entitled MET 102, Production design & Specifications (PD&S). Now in the fourth semester of use, IronCADTM has seen success in a multitude of projects, both in a variety of class assignments and wholly student initiated applications. As such solid modeling has now migrated into a number of other undergraduate and graduate courses and is well on the way to integration across the whole curriculum. Examples of ways students and faculty are utilizing this powerful tool are discussed below. P ge 7.055.1 Proceedings of the 2002 American Society for Engineering Education Annual Conference & Exposition Copyright ” 2002, American Society for Engineering Education To monitor this CAD integration process, a survey was assembled and emailed to all Purdue University MET faculty members in September, 2001 by one of the authors. The CAD software packages included in the survey included: IronCADTM, AutoCADTM , Pro/E, Solid-EdgeTM , Solid-WorksTM , and CatiaTM . This survey requested input on the faculty member’s overall interest level in CAD software relative to their teaching and/or applied research, their present specific CAD software utilization, their future anticipated CAD utilization, any corporate interest in specific CAD software packages expressed to the faculty member, and requested their input relative to which CAD software packages they would recommend if we had to choose two. The number of faculty indicating a “strong interest” was 15 out of 37. Of these “strongly interested” 15 respondents, 60% indicated a desire to utilize IronCADTM, 25% indicated a desire to utilize Pro/EngineerTM and 25% indicated a desire to utilize AutoCADTM in their future teaching and applied research. The results of this survey show an increasing future interest in both IronCADTM and Pro/EngineerTM, with a declining future interest in the other four CAD software packages included in the survey. PD&D Course Applications Production Design & Specifications is the second in a two-course sequence on CAD applications and is normally taken the second semester of the freshman year. It is schedule early in the plan of study so that the techniques and knowledge learned can be applied to all subsequent courses as required. The prerequisite to PD&S, offered as a service course by another department, teaches students the rudimentary operational skills of solid modeling. Following that PD&S serves as the core course where students learn to use CAD to apply tolerances, fits, and other design intent specifications in exercises that require construction of CAD models crossing a variety of disciplines and manufacturing processes. These include, castings, weldments, sheet metal parts (flat pattern development) and a variety of machined parts. Because of the prerequisite IronCADTM-based course using a standard textbook, when they enter PD&D, it is assumed that they know the basics of model creation and extraction of engineering drawings from the models. While completing the series of increasingly more complex models, students learn how to calculate tolerancing (inch & metric), allowances, limits calculations, geometric dimensioning & tolerancing and fits based on ANSI and ISO standards. They also learn to apply and document open-ended design modifications based on change orders, cost constraints, requirement for use of standard parts (fasteners, bearings, gears, etc.) and adherence to the ISO preferred number system. Figures 1 depicts examples of models generated by students in PD&S and others done independently by students for assignments in other classes. These models are described below start from the upper left corner and proceed clockwise: An assembled motor mount used as the final design stage in a PD&S project. After completion of the models, calculating fits, specifying standard parts, resolving a series of engineering change orders, and generating complete engineering drawings, students must animate the parts to simulate the assembly and operation process.