Sets the origin and orientation of the current user coordinate system (UCS).
Summary
The UCS is the active coordinate system that establishes the XY plane (work plane) and Z-axis direction for drawing and modeling. You can change the UCS origin and orientation for convenience as you specify points, enter coordinates, and work with drawing aids, such as Ortho mode and the grid.
A UCS can be stored with a viewport if the UCSVP system variable is set to 1 for that viewport.
List of Prompts
The following prompts are displayed.
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 to pass the positive X axis through this point.
- If you specify a third point, the UCS rotates around the new X axis to define the positive Y axis.
The three points specify an origin point, a point on the positive X axis, and a point on the positive XY plane.
If you do not specify a Z coordinate value when entering a coordinate, the current Z value is used.
Dynamically aligns the UCS to a face on a 3D object.
Move the cursor over a face to preview how the UCS will be aligned.
Saves or restores named UCS definitions.
Lists saved UCS definitions showing the origin and X, Y, and Z axes for each saved UCS definition relative to the current UCS. Enter an asterisk to list all UCS definitions. If the current UCS is the same as the WCS (World Coordinate System), it is listed as WORLD. If it is custom, but unnamed, it is listed as NO NAME.
Aligns the UCS to a selected 2D or 3D object. The UCS can be aligned with any object type except xlines and 3D polylines.
Move the cursor over an object to see a preview of how the UCS will align, and click to place the UCS. In most cases, the UCS origin will be located at the endpoint that is nearest to the specified point, the X axis will align to an edge or tangent to a curve, and the Z axis will align perpendicular to the object.
You can steps back through the last 10 UCS settings in the current session. UCS settings are stored independently for model space and paper space.
Aligns the XY plane of the UCS to a plane perpendicular to your viewing direction. The origin point remains unchanged, but the X and Y axes become horizontal and vertical.
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.
Aligns the UCS to a specified positive Z axis.
The UCS origin is moved to the first point and its positive Z axis passes through the second point.
