Orthographic Reading

1
Chapter 6 Orthographic Reading
2
TOPICS
3
DEFINITION
Reading a drawing is the process of recognizing
the shape of an object by interpreting the
orthographic views.
Orthographic Writing
Orthographic Reading
4
VIEWING DIRECTION
Given
5
ORTHOGRAPHIC READING
Analysis by Solids
6
BASIC IDEA
Objects can be decomposed into solid geometric
primitives.
Some of familiar solid geometry
7
VISUALIZATION STEPS
1. Choose an appropriate viewing direction
according to a given orthographic views.
2. Choose an area in orthographic views, relate
it to other views, and form a primitive
solid geometry.
3. Repeat step 2 until all areas are analyzed.
4. Combine all of primitive solid geometries
according to their positions in orthographic
views.
8
EXAMPLE A
Primitive solid geometry
9
EXAMPLE B
Primitive solid geometry
10
EXAMPLE C
Primitive solid geometry
Given
11
EXAMPLE D
Composition
12
EXAMPLE D
Composition
13
ORTHOGRAPHIC READING
Analysis by Surfaces
14
READING STEPS
1. Choose an appropriate viewing direction
according to a given orthographic views.
2. Choose an area or lines in orthographic views,
relate it to other views, and identify type
of a surface (or plane).
3. Sketch a pictorial view of a reading surface.
4. Repeat steps 2 and 3 until all surfaces are
read.
Knowing the types of surfaces is very important.
At this step, details of an object will gradually
build up.
15
Class Activity

• Complete page 1 of a given handout.
• Try to identify plane type.

0 min
2.5 min
5 min
7.5 min
10 min
Start
16
GUIDANCE 1
Different plane
Same plane
Line exists
Edge view
Edge view
17
EXAMPLE
All surfaces A, B andC are not lie in the same
plane.
Some of possible objects shape.
18
GUIDANCE 2
19
GUIDANCE 2
20
EXAMPLE A
21
EXAMPLE A
22
EXAMPLE A
23
EXAMPLE B
24
EXAMPLE B
25
EXAMPLE B
26
EXAMPLE B
27
EXAMPLE B
28
Missing View Problems
29
EXAMPLE A
30
EXAMPLE A
back
floor
31
EXAMPLE B
This area was hidden by yellow object
This line is green surface.
?
This line is pink surface.
32
EXAMPLE B
33
Class Activity

• Complete page 2 of a given handout.

0 min
5 min
10 min
15 min
20 min
Start
34
Enjoy doing a homework.
Prepare yourself for quiz 1 on next Monday.
Make an enough practice for Midterm Exam.