The Real-World Meets the Technical Drawing Curriculum
by FRANK SACCENTE, Instructor Roselle Park High School Roselle Park, N.J. In light of the difficulty faced by educators when trying to stress upon students the importance of academic curricula, an approach employed by a Technical Drawing program reveals some innovative methods for accomplishing this objective. The approach has been employed in the Technical Drawing program at Roselle Park High School in New Jersey for the past five years and encompasses the traditional drafting curriculum, but with a very different twist. The program couples the normally covered areas of a drafting curriculum with exposure to "real life," out-of-school examples of its application. Here's how it's done. By skimming the table of contents of any drafting text and then exercising some creativity and imagination, numerous opportunities can be found for bringing the curriculum to life in a fresh and exciting way and integrating it with other academic disciplines. Examples of such an approach follow below. Aerodynamics and CAD In a unit entitled The Physics of Flight, Roselle Park High's drafting students are first familiarized with the principles and concepts responsible for creating lift in an airfoil or airplane wing. For those who don't hold a degree in aeronautical engineering, this phenomenon is explained through such physics principles as the Venturi Effect, Bernoulli's Law and Newton's Third Law of Motion. After the initial introduction, students then conduct library research to gather information on the above principles and are asked to define some common aeronautical engineering terminology. Next, a model-making exercise is provided in which students apply the above concepts and terms and generate flat, stretchout patterns for various types of paper airplanes. Students use the AutoCAD computer-aided drafting program to generate their paper airplane patterns and to add graphics and personalized text before outputting the pattern to a Houston Instruments' DMP 52 plotter. The accuracy obtainable through a high-end CAD system such as this enables students to not only develop accurate multi-scaled patterns, but also helps them make wing surface-area calculations. These area calculations are then used during "test flights" of their paper prototype airplanes in the corridor, to determine when and if an increase in wing surface area leads to an increase in flight stability and duration. Now it's time for the real-life example. This was accomplished by arranging to have the United States Coast Guard land one of its search and rescue helicopters on the school's athletic field. During the course of a three-hour demo by the chopper's Coast Guard crew, students saw the real-world application of all of the principles and concepts that were covered in class. The reinforcement and resultant retention of the subject matter by students through a dramatic field experience such as this is unparalleled in terms of a lasting impression. The chopper demo also provided an ideal venue to stress upon students the critically important role that math and science play not only in aircraft design, but also in every aspect of our day-to-day lives. Machine Drafting and Cars Another area ripe for accessing a wealth of "real life" reinforcement is machine drafting. This topic is typically covered in high school drafting programs and usually requires students to generate drawings of what they perceive to be meaningless, abstract shapes. In spite of its importance, it's tough to get a high school adolescent excited about a roller bearing and pulley assembly. But there is a better way. Instead, through a unit entitled Automotive Concepts and Technology, Roselle Park students switch from the mundane task of creating drawings of abstract machine parts to delving into the much more interesting and numerous concepts associated with automotive design, engineering and manufacturing. This area is easily laced with math and science principles and concepts. For example, the calculation of horsepower provides an excellent vehicle for exposing students to the mathematical formula used to determine the volume of a piston cylinder; similarly, the physics involved in converting reciprocal motion into rotary motion is easily understood when related to a crankshaft and piston assembly. Compression ratios are a natural discussion area, as is the chemistry behind varying volatility levels of different octane gasolines. In terms of generating ideas for integrating math and science into the drafting curriculum, the automotive world would have to be considered the mother lode. A hands-on experience is provided through an abstract machine exercise in which students once again employ AutoCAD in a number of different ways. First, when drawing cam patterns that will later be used to fabricate working prototype cams, the extremely complicated and exacting layout process is greatly simplified by the accuracy and precision afforded by this industry-standard CAD system. Angle layouts and precise incremental measurements related to such cam functions as rise, dwell and drop can be made with the click of a mouse button. Cam drafting is also simplified and made less cumbersome through the use of the fit curve CAD function, which enables students to plot smooth compound curves through numerous points. AutoCAD is also used throughout the abstract machine-design exercise to study the working mechanism's motion while it is still on the computer screen. This is accomplished by first having students generate drawings of individual parts -- cams, connecting rods and bell cranks -- and then storing them in an AutoCAD block file. These stored parts can then be called out and inserted onto the computer screen at different angles of rotation or positions, enabling a student to observe the motion of the part as it revolves or reciprocates. This in turn allows a visual inspection for clearances and desired degrees of motion before the drawing and subsequent idea is ever committed to paper. By using a sophisticated CAD program, the time required by students to generate drawings is greatly reduced. This leaves much more time for generating ideas. The real-life example for this unit was provided by having students tour a local facility that designs, fabricates and assembles race cars for a national racing circuit. This experience exposed students to machine design at one of its most sophisticated levels. Finally, the new approach to this unit moves students away from the more traditional drawing-based drafting program to a more concept-oriented program. Not only d'es this enable students to develop a real understanding of the concepts behind and functions of automotive components, but it also naturally fosters a heightened interest level and a more inquiring mindset. Technical Writing and DTP Another basic topic in the curricula is technical writing. In a unit entitled How Things Work, students develop technical writing skills by choosing a topic that explores the operation of a machine or mechanism. After gathering information from library research and industry- and manufacturer-based sources, students describe the operation of their mechanism by combining text and drawings. The document is created in class using PageMaker DTP software. The end result is similar to the owner's manuals of many products used every day. Conclusion By implementing exercises such as these, students develop a basic understanding of concepts and skills in disciplines such as math, science, library research, information retrieval, writing and drawing. And due to the varied nature of the topics selected, this class format lends itself to individualized assignments that lead to a higher student success rate, given the heterogeneous ability level usually found in these classes. Although this individualized-project approach represents additional work for an instructor, student gains will be noticeable in terms of both a heightened interest level and an increased frequency of task success. In many cases, the feeling of accomplishment derived from this increased success rate manifests itself in the emergence of a "can-do" mindset on the part of students, which enhances their chances of overall educational success. The most important benefits of getting students out of the building to experience real-life examples of subject matter covered in class are easily summarized. First, it helps students realize the importance of their Technical Drawing curriculum, without which the world of manufactured consumer goods that make up the modern conveniences of everyday life would cease to exist. Second, by lacing the traditional drawing curriculum with topics such as math, science and writing, the critical interdependent role between all disciplines is stressed. This in turn can lead to a positive attitudinal change towards school in general that eventually fosters greater academic success. Frank Saccente has been an instructor of Technical Drawing and Technology Education in the Roselle Park School System for the past 17 years and teaches at the high-school level. Products or companies mentioned: AutoCAD; Autodesk, Inc., Sausalito, Calif. DMP 52 plotter; Houston Instruments, Inc., Houston, Texas PageMaker; Aldus Corp., Seattle, Wash.