Commands > U commands >

Manages user coordinate systems.

Button

Ribbon: View tabCoordinates
panelWorldNot available on the ribbon in
the current workspace

Menu: ToolsNew
UCSWorldNot available in menus
in the current workspace

Toolbar: UCS

The following prompts are displayed.

Specify Origin of UCS or [Face/NAmed/OBject/Previous/View/World/X/Y/Z/ZAxis] <World>:

Defines a new UCS using one, two, or three points.
If you specify a single point, the origin of the current UCS shifts
without changing the orientation of the *X*, *Y*,
and *Z* axes.

If you specify a second
point, the UCS rotates around the previously specified origin point such
that the positive *X* axis of the UCS passes through
the point.

If you specify a third
point, the UCS rotates around the *X* axis such
that the positive *Y* half of the *XY* plane of
the UCS contains the point.

The three points specify
an origin point, a point on the positive *X* axis, and a
point on the positive *XY* plane.

Aligns the user coordinate system to a face on a 3D solid.

Select a face by clicking
within the boundary or on an edge of the face. The UCS *X* axis
is aligned with the closest edge of the original face selected.

Save and restore commonly used UCS orientations by name.

Aligns the user coordinate system to a selected object.

The positive Z axis of the UCS is aligned perpendicular to the plane in which the object was originally created.

The following objects cannot be used to align a UCS: 3D polylines and xlines.

For most objects, the origin of the new UCS is located at the nearest vertex to where you select the object, and the X axis is aligned with an edge or is tangent to an edge. For planar objects, the XY plane of the UCS is aligned with the plane in which the object is located. For complex objects, the origin is relocated, but the current orientation of the axes is maintained.

For
objects other than 3D faces (available only when viewing AutoCAD^{} drawings),
the *XY* plane of the new UCS is parallel
to the *XY* plane in effect when the object
was drawn. However, the *X* and *Y* axes can be
rotated differently.

The new UCS is defined as shown in the following table.

The last 10 user coordinate systems created in model space and the last 10 created in paper space layouts are retained. Repeating this option steps back through one set or the other, depending on which space is current.

Aligns the *XY* plane of
the user coordinate system to a plane perpendicular to your viewing
direction. The origin point remains unchanged, but the *X* and *Y* axes
become horizontal and vertical.

Sets the current user coordinate system to the world coordinate system (WCS).

The WCS is the basis for all user coordinate systems and cannot be redefined.

Rotates the current UCS about a specified axis.

Point your right thumb
in the positive direction of the *X* axis and curl
your fingers. Your fingers indicate the positive rotation direction
about the axis.

Point your right thumb
in the positive direction of the *Y* axis and curl
your fingers. Your fingers indicate the positive rotation direction
about the axis.

Point your right thumb
in the positive direction of the *Z* axis and curl
your fingers. Your fingers indicate the positive rotation direction
about the axis.

You can define any UCS by specifying an origin and
one or more rotations around the *X*, *Y*,
or *Z* axis.