7. Coordinate System and
Snaps Application
Absolute coordinates
Relative coordinates
Direct distance entry
Objects snap
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8. Coordinate Systems
AutoCAD uses the following coordinate systems to
locate a point in an XY plane.
1.
2.
3.
Absolute coordinates
Relative coordinates
- Relative rectangular coordinates
- Relative polar coordinates
Direct distance entry
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9. Coordinate Systems
• Absolute coordinates
- points are located with respect to the origin (0,0)
Command: Line
(10,50)
(50,50)
(50,10)
(10,10)
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10. Coordinate Systems
• Relative rectangular coordinates
- the displacements along X,Y axes are measured
with reference to the previous point rather than to
the origin (0,0)
Command: Line (@-50,0)
(@0,-50)
(@0,50)
(@50,0)
(10,10)
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11. Coordinate Systems
• Relative polar coordinates
- defining both the distance of the point from current
point and the angle
Command: Line
(@50<30)
(10,10)
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12. Coordinate Systems
• Direct distance entry
- the direction is determined by the position of the
cursor
Command: Line
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13. Snap Application
• Object snaps (OSNAP) - to improve
performance/accuracy and make drafting simpler
• Keyboard Shortcut ON/OFF: F3
• Command: OSNAP
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14. Snap Application
• OSNAP Overrides
- Use SHIFT + Right-click and select the object snap from
the shortcut menu
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17. UCS
World Coordinate System (WCS)
•
•
Fixed origin (0,0,0) located at the lower left corner by
default and cannot be removed.
WCS is generally used in 2D drawings, wireframe
models and surface models.
Why UCS?
make easier in create a feature.
UCS allows to relocate and reorient the origin depends
to user, mostly used in 3D.
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18. UCS
Conventions in AutoCAD
- ‘Right-hand rule’ – identify the X,Y,Z axes direction.
‘Right-hand thumb rule’
- Identify the direction
of rotation in 3D space.
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