The Development and Effects of Teaching Perspective Free-Hand Sketching in Engineering Design
As Computer-Aided Design software has become more advanced, the use of hand-drawn engineering drawings has greatly diminished. This reduction has led to free-hand sketching becoming less emphasized in engineering education. While many engineering curriculums formerly included courses dedicated entirely to sketching and hand drafting, these topics are no longer addressed by most current curriculums. However, it has been observed that sketching has many benefits including improved communication in the design process, idea generation exercises, and visualizing design ideas in threedimensional space. While isometric sketching has long been the preferred method in engineering curriculums, there are benefits of teaching perspective sketching including the creation of more realistic sketches for communication and idea generation. This paper presents the development of a perspectivebased sketching curriculum and the study of how this method compares to more traditional methods of teaching sketching to students in a freshman level engineering graphics course. The results show that the perspective-based sketching method leads to equivalent gains in spatial visualization skills and final design self-efficacy as the traditional method of teaching hand sketching. While maintaining these skills, the new method also taught students additional skills. Through surveys and interviews, the students expressed that these skills would be useful to them in their future coursework and careers. INTRODUCTION Several benefits have been found for teaching engineering students how to sketch. These include improving visualization skills, serving as stepping stones in the development of effective prototypes, and assisting in the design process by providing a method of tracking and developing ideas [1-5]. The traditional method of teaching sketching does prepare students to use the more modern CAD methods of creating representations by focusing on the sketching of simple objects in two-dimensional and isometric views and less on techniques to draw an object in realistic three-dimensions such as shading and perspective. While the CAD-focused method has been found useful in some applications, it runs the risk of missing out on benefits such as being able to quickly sketch to communicate an idea. Improving spatial visualization skills is often a critical outcome for CAD and visualization courses. Sorby (2009) says that the best way to improve these spatial skills is to “sketch, sketch, sketch” [1], but the more traditional method taught in engineering course does not focus on freehand sketching. Therefore, in a freshman-level mechanical/aerospace engineering course at Georgia Tech, we have begun to develop a more form and technique-based method of teaching free-hand sketching that is more commonly found in an Industrial Design or Architecture course. As spatial visualization has been found important in many fields, there have been several tools developed to test these skills including the Purdue Spatial Visualization Test (PSVT) developed by Bodner and Guay (1997) and revised by Yoon (2011) and the Mental Rotation Test (MRT) developed by Vandenburg & Kuse (1978) and Peters (2006) [6-11]. Also, curriculum changes or additions could affect Self-Efficacy for Engineering Design. Therefore, Carberry (2010) developed a method to determine design self-efficacy through four aspects: confidence, motivation, perceived success, and anxiety in performing engineering design tasks [12].