PowerPoint Presentation: Chapter 3 Orthographic Projection
PowerPoint Presentation: TOPICS Object representation Glass box concept Line convention Orthographic projection of point , line , plane , surface and object . Multiview projection
PowerPoint Presentation: OBJECT REPRESENTATION Axonometric projection Multiview projection
PowerPoint Presentation: MULTIVIEW PROJECTION Three principle dimensions of an object … Width Depth Height Width Height Depth Depth … can be presented only two in each view. Adjacent view(s) is needed to fulfill the size description.
PowerPoint Presentation: Revolve the object with respect to observer . TO OBTAIN MULTIVIEW REPRESENTATION OF AN OBJECT The observer move around the object.
PowerPoint Presentation: REVOLVE THE OBJECT Front view Right side view Top view
PowerPoint Presentation: OBSERVER MOVE AROUND Front view Right side view Top view
PowerPoint Presentation: THE GLASS BOX CONCEPT Bottom view Left side view Rear view
PowerPoint Presentation: Height Width Depth History
PowerPoint Presentation: MULTIVIEW PROJECTION Click on the picture to play video
PowerPoint Presentation: MULTIVIEW PROJECTION Click on the picture to play video
PowerPoint Presentation: MULTIVIEW PROJECTION Click on the picture to play video
PowerPoint Presentation: MULTIVIEW PROJECTION Click on the picture to play video
PowerPoint Presentation: Orthographic Projection of Object Features
OBJECT FEATURES: OBJECT FEATURES Edges are lines that represent the boundary between two faces. Corners Represent the intersection of two or more edges. Edge Corner Edge No edge No corner No corner
PowerPoint Presentation: Surfaces are areas that are bounded by edges or limiting element. Limitingelement is a line that represents the last visible part of the curve surface. Surface Surface Surface Limit Limit OBJECT FEATURES
PowerPoint Presentation: A B PROJECTION OF POINT(S) A F B R A T B F A R B T A F A R A T B F B R B T Equal distance
PowerPoint Presentation: A B A F B F B R A R A T B T B R A R A F B F A T B T True length NORMAL LINE True length Point Equal length PROJECTION OF LINE
PowerPoint Presentation: A B A F B F B R A R A T B T INCLINED LINE Foreshortened B R A R A F B F Foreshortened A T B T True length A Equal length PROJECTION OF LINE
PowerPoint Presentation: A B A F B F B R A R A T B T OBLIQUED LINE A Equal length B Foreshortened Foreshortened Foreshortened B R A R A F B F A T B T PROJECTION OF LINE
PowerPoint Presentation: B C A PROJECTION OF PLANE B F A F ,C F C R A R ,B R A T C T NORMAL PLANE Equal length Edge Edge True size C R A R ,B R A F ,C F B F A T B T C T B T
PowerPoint Presentation: B C B F A F C R A R ,B R A T C T INCLINED PLANE A Equal length B T C C F Edge C R A R ,B R Foreshortened B T C T A T A F C F Foreshortened B F PROJECTION OF PLANE
PowerPoint Presentation: B C B F A F C R A R A T C T OBLIQUED PLANE A Equal length B T C C F B B R Foreshortened C R A R B R A F B F C F Foreshortened A T B T C T Foreshortened PROJECTION OF PLANE
PowerPoint Presentation: PROJECTION OF OBJECT The views are obtained by projecting all object features to the picture plane. You have to project the remaining surfaces which are invisible too !
PowerPoint Presentation: s s s PROJECTION OF OBJECT
PowerPoint Presentation: PROJECTION OF OBJECT
PowerPoint Presentation: Line Convention
PowerPoint Presentation: LINE CONVENTION Precedence of coincide lines. Hidden line drawing. Center line drawing.
PowerPoint Presentation: PRECEDENCE OF LINE Visible line Order of importance Hidden line Center line
PowerPoint Presentation: HIDDEN LINE PRACTICE Hidden line should join a visible line, except it extended from the visible line. Correct No ! Join Leave space
PowerPoint Presentation: Correct No ! Hidden line should join a visible line, except it extended from the visible line. Leave space Leave space HIDDEN LINE PRACTICE
PowerPoint Presentation: Hidden line should intersect to form L and T corners. Correct No ! L T HIDDEN LINE PRACTICE
PowerPoint Presentation: Hidden arcs should start on a center line. HIDDEN LINE PRACTICE
PowerPoint Presentation: CENTER LINE PRACTICE In circular view, short dash should cross at the intersections of center line. For small hole, center line is presented as thin continuous line. Center line should not extend between views. Leave space Leave space
PowerPoint Presentation: Leave the gap when centerline forms a continuation with a visible or hidden line Leave space Leave space Leave space Leave space Center line should always start and end with long dash. CENTER LINE PRACTICE