Introduction to TechnologyChapter 5:
From Drawings to PrototypesChapter SummariesSection 5.1
Drawings are used by scientists, architects, engineers, designers, and illustrators to show what objects look like. A drafter makes a freehand sketch to show the shape and size of an object. To draw an accurate picture, drafters use rules, compasses, and other mechanical drawing tools. A multiview drawing shows the front, top, and right views. A section drawing shows internal structure. Pictorial drawings are also done. Section 5.2
Drafters represent an object by using different kinds of lines. Thickness and length are determined by the rules of drafting. Dimensions give the size and location of the object’s features. In CAD, the designer creates and tests his or her designs on the computer. Most made objects are first drawn. Drawings larger or smaller than the real object are drawn to scale; the parts are in the correct proportions. Section 5.3
A model is a replica of the product; however, it does not work. A prototype does work and may be tested for reliability or safety. Rapid prototyping makes replicas from plastic. The replicas are first drawn with CAD software, which is also used to make models for scientific and engineering visualization for research and testing.  | 
