UNDERSTANDING ORTHOGRAPHIC PROJECTIONS IN DESCRIPTIVE GEOMETRY THROUGH THE LIGHT–SHADOW ANALOGY
Keywords:
descriptive geometry; orthographic projection; engineering graphics education; spatial visualisation; technical drawing; projection methods.Abstract
Descriptive geometry and technical drawing continue to play a central role in engineering education, offering essential tools for representing three-dimensional objects on two-dimensional surfaces. Yet many students find orthographic projections difficult to understand, especially when first encountering the logic behind view placement. This paper proposes a conceptual teaching approach based on a simple but effective analogy: imagining an object illuminated so that its shape appears as a shadow on a projection plane. This mental model helps students better understand why views are arranged as they are in technical drawings, particularly in first-angle projection systems. The paper discusses the conceptual background of this approach and reflects on its pedagogical value in supporting spatial understanding and graphical communication skills.
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