Chungnam National University 1

형상의 표현방법 (투상법)METHODS OF SHAPE DESCRIPTION (projection)

Lesson 4

투상법

제 3 각법

투상도 표현

Freehand sketch

Chungnam National University 2

METHOD OF SHAPE DESCRIPTION

3D Objects must be represented on flat paper(2D) in

such a manner that the exact shape can be

understood easily

How we can do this?

Draw a number of separate views of the object as

seen from different positions, then arrange those

views in a systematic manner

Projection views (투상법)

Chungnam National University 3

PROJECTION (투상법)

Chungnam National University 4

PROJECTION (투상법)Projection system

(투상법)

Perspective Projection

(투시투상)

Parallel Projection

(평행투상)

Orthographic Projection

(수직투상)

Oblique Projection

(사투상)

Multiview Projection

(정투상)

Axonometric Projection

(축측투상)

1st, 2nd, 3rd, 4th angle

(일, 이, 삼, 사각법)

Chungnam National University 5

ORTHOGRAPHIC PROJECTION

The principles of orthographic projection can be

applied in four different "angles" or systems; 1st, 2nd,

3rd, 4th angle projection.

Chungnam National University 6

THIRD ANGLE PROJECTION

Chungnam National University 7

THIRD ANGLE PROJECTION

Chungnam National University 8

Comparison between 3rd and 1st angle projection

Chungnam National University 9

Comparison between 3rd and 1st angle projection

제 3 각법

제 1 각법

Chungnam National University 10

LINE TYPES IN PROJECTION VIEWS

Solid Line

Chungnam National University 11

Dashed Line

LINE TYPES IN PROJECTION VIEWS

Chungnam National University 12

Center Line Dimension Line

LINE TYPES IN PROJECTION VIEWS

Chungnam National University 13

SELECTION OF VIEWS IN PROJECTION

Selection of views

Chungnam National University 14

NUMBER OF VIEWS IN PROJECTION

One view drawing

Except for complex objects of irregular shape, it is

seldom necessary to draw more than three views.

Chungnam National University 15

Two view drawing

NUMBER OF VIEWS IN PROJECTION

Chungnam National University 16

Three view drawing

NUMBER OF VIEWS IN PROJECTION

Chungnam National University 17

Devices for freehand sketch: pencil and eraser

because freehand sketch is for fast communication

Freehand sketch example

FREEHAND SKETCH

Chungnam National University 18

FREEHAND SKETCH TECHNIQUE

반지름이작은원의스케치 반지름이큰원의스케치

Chungnam National University 19

FREEHAND SKETCH TECHNIQUE

직사각형법을응용한투상도스케치

직사각형법을이용한비례위치찾기

Chungnam National University 20

FREEHAND SKETCH FOR ISOMETIC VIEWS

Chungnam National University 21

FREEHAND SKETCH FOR PROJECTION VIEWS

투상도를스케치하는순서

Chungnam National University 22

FREEHAND SKETCH HOME WORKS

브래킷 링크