Description of the Alignment Utilities Dialog Box

When you select Insert | Alignment | New (or press F9 on an existing alignment command), PC-DMIS displays the Alignment Utilities dialog box. This dialog box provides a way for you to construct an alignment from the features that have been measured up to that point in the measurement routine.

An alignment is not complete until you select the OK button and PC-DMIS updates the Active Alignment List box.

As long as the Alignment Utilities dialog box remains open, PC-DMIS indicates any remaining unconstrained degrees of freedom by causing the XYZ origin symbol (or alignment trihedron) to continually rotate about and translate in the direction of those unconstrained axes in the Graphic Display window. Once the alignment is completely constrained, PC-DMIS then displays the trihedron in a fixed location and orientation that represent the alignment position:

This box defines the identification for the current alignment. If you are creating a new alignment, the alignment ID will default to a new name. To change the ID, type a new value in this box and press TAB.

The Recall list contains all the internal alignments that have been defined in the measurement routine prior to this alignment. The alignment selected from this Recall list acts as the start condition of the current alignment.

If you are creating a new alignment, the Recall list will display the alignment active at the cursor's current location in the Edit window. If you have not defined any alignment, or if the cursor location is before any defined alignments in the Edit window, the STARTUP command is selected as the recalled alignment.

You can recall any available alignment listed in the Recall list. Only alignments created prior to the current cursor's position and certain predefined special cases are available for selection from that list.

These special cases include:

STARTUP - You can recall the STARTUP alignment automatically defined at the start of the measurement routine.

USE_ACTIVE_ALIGNMENT - See the "ID" description in the "Start Alignment Command" topic for more information.

USE_PART_SETUP - See the "ID" description in the "Start Alignment Command" topic for more information.

This list displays a summary of each of the sub-commands that make up the current alignment block. This summary includes information such as the type of alignment sub-command, axis direction, and feature or features used by the sub-command to perform its rotation and/or translation.

While you can edit any existing Level, Rotate, or Origin alignment sub-command inside the Summary or Command modes of the Edit window, you can also edit an existing sub-command by clicking on its entry in the sub-command list and making the needed change. Once you select an item, the appropriate area of the Alignment Utilities dialog box becomes available to edit. After you've edited the item, click the related sub-command button (Level, Rotate, or Origin) to modify the alignment.

For example, if you wanted to modify the feature to which the alignment was leveled, you would select the "leveled to" item in the list. PC-DMIS will display the current feature used for the leveling portion of the alignment, and then it would make the Level button available.

Simply select the new feature and axis, and click Level. PC-DMIS updates the Alignment Sub-Command list to reflect your changes.

To deselect an item from the Alignment Sub-Command list, click on that item a second time, or press the ESC key on the keyboard.

The Delete button deletes the currently-selected sub-command from the Alignment Sub-Command list.

The Best Fit button opens the Best Fit dialog box. Use this dialog box to create or edit Best Fit alignments. See the "Creating a Best Fit Alignment" topic.

The Iterative button opens the Iterative Alignment dialog box. Use this dialog box to create and edit Iterative alignments. See the "Creating an Iterative Alignment" topic.

The Available features area displays all the available features in your measurement routine that exist above the current cursor location. These are the features available to your current alignment command.

You can also use the Graphical Hit Selection method to select inputs to your alignment. For details, see "Graphical Hit Selection Method".

The Search ID filters the list of features by the specified ID. Type the ID string, and press TAB.

The Select last # box-selects the final 'N' features in the list, where 'N' is the number you type. Type the number of features to select, and press TAB.

The Level area establishes the orientation of the normal axis of the current workplane.

The Level button only becomes active if you first select a feature from the feature list or an existing level sub-command (ALIGNMENT/LEVEL). If you select an existing level sub-command, it will be modified to use the new feature selection; otherwise, a new level sub-command will be created using the selected feature.

You may also specify the axis to be used in establishing the orientation by selecting it from the drop-down list. The available options are:

ZPLUS

XPLUS

YPLUS

ZMINUS

XMINUS

YMINUS

After you click the Level button, the Alignment Utilities dialog box changes the About list next to the Rotate button to automatically match the Level button's axis direction.

The Edit window command line for this option reads:
ALIGNMENT/LEVEL,ZPLUS,'feat_id'

Changeable fields:
"ZPLUS"
This is a field that allows you to switch between the ZPLUS, XPLUS, YPLUS, ZMINUS, XMINUS, and YMINUS fields in the Edit window. This field represents the direction of the specified axis that the feature is leveled to.

"feat_id"
The alignment levels to the specified feature.
Example: PLANE1.

The Rotate area rotates the alignment to be parallel to a selected feature by a specific manual offset angle or by an angle defined from a picked CAD surface or edge.

PC-DMIS rotates the Rotate to axis around the alignment origin, about the specified alignment axis (About axis). The Rotate to and About axes cannot be the same axis.

To rotate to a measured feature:

Select the proper reference feature from the Feature List box in the Alignment Utilities dialog box.
Specify the axis to rotate to in the Rotate to list.
Specify the axis to rotate about in the About list.
Click the Rotate button.

The Rotate button only becomes active if you first select a feature from the feature list or select an existing rotate sub-command (ALIGNMENT/ROTATE). If you select an existing rotate sub-command, it is modified to use the new feature selection Rotate to axis and Rotate About axis; otherwise, a new rotate sub-command is created using the selected feature and axis settings.

The Edit window command line for this option reads:
ALIGNMENT/ROTATE,XPLUS,to,'feat_id',about,ZPLUS

Changeable fields:
"XPLUS","ZPLUS"
This is a toggle field that allows you to toggle between these fields in the Edit window:

ZPLUS

XPLUS

YPLUS

ZMINUS

XMINUS

YMINUS

PC-DMIS will set this axis parallel to the specified input feature. It will then rotate about the second axis.

"feat_id"
The alignment rotates parallel to the specified feature. Example: LINE1.

To rotate to the line between two circles, select two circles in the Available Features list instead of a single feature and then continue with the "Rotate to a Feature" procedure described above.

The Edit window command line for this option reads:
ALIGNMENT/ROTATE_CIRCLE,ID, ID

Changeable fields: "ID"

This is one of the two ids to which to rotate.

The Offset angle box allows you to rotate the alignment by a specified angle about a selected axis.

To rotate by an offset:

Select the axis to rotate about from the About list.
Type the desired angle in the Offset angle box.
Click the Rotate button.

The Rotate button becomes active once you type a value in the Offset angle box or select an existing rotate offset sub-command (ALIGNMENT/ROTATE_OFFSET). If you select an existing rotate offset sub-command, it is modified to use the new Offset angle value; otherwise, a new rotate offset sub-command is created.

If you click Rotate, and you have a feature selected and a value entered in the Offset angle box, the software creates these two sub-commands:

First, it creates a ROTATE command to the selected feature.
Second, it creates a ROTATE_OFFSET command with a value from the Offset angle box.

The Edit window command line for this option reads:
ALIGNMENT/ROTATE_OFFSET,'numeric_value',ABOUT,'AXIS'

Changeable field: "numeric_value"
This is the value the alignment will be rotated by in degrees of angle (for example; -14.36). The rotation will be about the axis, perpendicular to the active workplane. The rotation will be clockwise if the angle is negative and counter clockwise if the angle is positive.

Changeable field: "axis"
This is the axis about which the alignment will be rotated.

If you don't select a feature, and you type in a rotation Offset angle value, PC-DMIS follows the right-hand rule of rotation. PC-DMIS follows the convention to treat both the negative and positive axes as positive. This means PC-DMIS always rotates about the XPLUS, YPLUS, or YPLUS axis. It does this even if you select XMINUS, YMINUS, or ZMINUS. Positive offset angle values go in the positive direction (counter-clockwise), and negative values go in the negative direction (clockwise). The software enables the Rotate to list when you select a feature that controls an axis that matches the vector of the selected feature.

To rotate the alignment by an offset angle by means of picking a surface or edge on the CAD model:

From the Rotate to list, select the axis to which you want the alignment to rotate.
From the About list, select the axis about which you want the alignment to rotate.
Click the Pick in CAD icon .
PC-DMIS enters a special CAD-selection mode where the other dialog box controls are disabled until you either select a surface or edge from the CAD model, or you cancel this mode by clicking the icon again.
Once in this CAD-selection mode, click on the desired CAD model's surface or edge in the Graphic Display window to define the alignment rotation offset angle.
If the initial CAD selection does not define a valid rotation direction, PC-DMIS waits for a second CAD model selection and uses that with the first picked item to define the rotation direction.

PC-DMIS supports picking planar features, axial features (cylinders, cones, and lines), and point-type features (spheres, arcs, and ellipses).

For a given CAD feature selection, the following apply:

If you pick a planar feature, the plane's normal is used as the rotation direction.
If you pick an axial feature, the feature axis is used as the rotation direction. If the feature axis is parallel to the selected About axis, you must select a second feature to define the rotation direction perpendicular to the axis.
If you pick a point-type feature, you must select a second feature to define the rotation direction.
If you picked two axial features to define the rotation direction, the axes of the two features must be parallel.
If the picked item cannot be used to define an offset angle, PC-DMIS displays an error message and then lets you pick a different feature or cancel the CAD-selection mode.
If the resulting angle is 0, no offset sub-command is created.

The Edit window command line for this option is identical to the "Rotate by a Manual Offset Angle" case described above.

The Origin area moves the alignment origin to a specific feature location, by a specific manual offset distance, or by a distance defined from a picked CAD surface or Edge.

To move the alignment origin to a feature:

Select the feature to move to.
Choose the alignment axis direction or directions to move the origin by selecting the appropriate check box or check boxes (X, Y, Z, or Auto).
Click the Origin button. The Auto check box chooses the axes to move based on the feature type, the orientation of the feature, and the workplane.

The Edit window command line for this option reads:
ALIGNMENT/TRANS,ZAXIS,'feat_id'

Changeable fields:
"ZAXIS"
This is Edit window field allows you to switch between the fields ZAXIS, XAXIS, and YAXIS. This field represents the axis that the origin will be moved along to match the input 'feat_id'.

"feat_id"
This is the feature the alignment will set the origin to, along the given axis. Example: CIRCLE1.

To move the origin by a manually-specified offset distance:

Choose the alignment axis direction or directions to move the origin by selecting the appropriate check box or check boxes (X, Y, Z, or Auto).
Type the desired value in the Offset distance box.
Click the Origin button.

When you click Origin, if you have a feature selected, and you have a value entered in the Offset distance box, the software creates two sets of sub-commands:

First, it creates a set of TRANS commands to translate to the selected feature, based on the selection state of the X, Y, Z, and Auto check boxes.
Second, it creates a set of corresponding TRANS_OFFSET commands using the value from the Offset distance box.

The Edit window command line for this option reads:
ALIGNMENT/TRANS_OFFSET,ZAXIS,'numeric_value'

Changeable fields:
"ZAXIS"
This Edit window field allows you to switch between the fields ZAXIS, XAXIS, and YAXIS. This field represents the axis along which the origin moves. The distance moved is based on the 'numeric_value'.

"numeric_value"
This is the value by which the alignment is offset (for example, 5.12). A positive value moves along the defined axis in the positive direction. A negative value moves in the negative direction.

To move the origin by an offset by means of picking a surface or edge on the CAD model:

Choose the alignment axis direction or directions to move the origin by selecting the appropriate check box or check boxes (X, Y, Z, or Auto).
Click the Pick in CAD icon .
PC-DMIS enters a special CAD-selection mode where the other dialog box controls are disabled until you either select a surface or edge from the CAD model or you cancel this mode by clicking the button again.
Once in this CAD-selection mode, click on the desired CAD model's surface or edge in the Graphic Display window to move the alignment to the picked item.

PC-DMIS supports picking planar features, axial features (cylinders, cones, lines), and point-type features (spheres, arcs, ellipses).

For a given CAD feature and set of alignment axis directions:

If there is a unique solution point between the CAD feature and specified alignment axis directions, PC-DMIS moves the alignment to that point as allowed by the selected alignment axes (such as a single alignment axis and a planar feature).
If there is more than a single solution point, PC-DMIS moves the alignment to the solution point nearest the current alignment location as allowed by the selected alignment axes (such as two alignment axes and a planar feature intersecting at a line).
Marking the Auto check box behaves the same as selecting X, Y and Z.
If the selected CAD entity cannot be used to define an offset, PC-DMIS displays an error message and then lets you pick a different feature or cancel the CAD-selection mode.
If the resulting offset distance for a specific alignment direction is 0.0, no corresponding offset sub-command is created for that direction.

The Edit window command line for this option is identical to the "Move by a Manual Offset Distance" case described above.

The Auto-set Origin for Level/Rotate check box works together with the Level and Rotate buttons. If it is selected when you select a feature and click Level or Rotate, the same feature used to define the level or rotate sub-command is used to automatically create one or more translate origin commands. If there are two features selected (for a rotate command), only the first feature is used. The translation commands are based on the current X, Y, Z, or Auto settings in the Origin area.

The Auto-align button uses the currently-selected features to automatically create the alignment sub-commands. The Auto-align button is active only when exactly one, two, or three features are selected from the list of available features, and there are no sub-commands currently defined for the alignment. Auto-align uses the same algorithms as QuickAlign. Auto-align supports all valid combinations of features selected.

The CAD = Part (CAD Equals Part) button moves and orients the part origin defined by the alignment so that it is equal to the CAD origin. This option should be used after a created alignment places the part origin and orientation at the same location as the CAD origin and orientation. This can make it simpler to use the CAD data to help inspect the part by displaying the measured data directly on top of the CAD data.

The CAD = Part button is only available if the alignment is at the very end of the measurement routine. If there are other commands after the alignment, PC-DMIS hides the button.