Measuring Properties ()

• Measuring properties
• Measuring Properties in a Local Axis System

Measuring Properties

Insert the following sample model files: ATOMIZER.model, BODY1.model, BODY2.model, LOCK.model, NOZZLE1.model, NOZZLE2.model, REGULATION_COMMAND.model, REGULATOR.model, TRIGGER.model and VALVE.model.

They are to be found in the online documentation file tree in the common functionalities sample folder cfysm/samples.

1. Switch to Design Mode (Edit > Representations > Design Mode).

2. Set View > Render Style to Shading with Edges.

   You cannot use this command, if Shading only is selected

3. Click Measure Item . In DMU, you can also select Analyze > Measure Item from the menu bar. The Measure Item dialog box appears.

   By default, properties of active products are measured with respect to the product axis system. Properties of active parts are measured with respect to the part axis system.  Note: This distinction is not valid for measures made prior to Version 5 Release 8 Service Pack 1 where all measures are made with respect to the absolute axis system.

4. Set the desired measure mode in the Selection 1 mode drop-down list box.

5. Set the desired calculation mode in the Calculation mode drop-down list box.

6. Click to select the desired item.

   	Note: The appearance of the cursor has changed to assist you.
   The dialog box gives information about the selected item, in our case a surface and indicates whether the result is an exact or approximate value. The surface area is also displayed in the geometry area. The number of decimal places, the display of trailing zeros and limits for exponential notation is controlled by the Units tab in the Options dialog box (Tools > Options, General > Parameters and Measure). For more information, see the Infrastructure User's Guide.

7. Try selecting other items to measure associated properties.

   	Note:  For reasons of legibility, angles measured by Angle by 3 points or on an arc of circle of less than 0.02 radians (1.146 degrees) are not displayed in the geometry area.

8. Click OK when done.

   If you checked the Keep Measure option in the Measure Item dialog box, your measures are kept as features and your specification tree will look something like this if properties of the active product were measured.
   Or like this, if properties were those of the active part.
   	Notes: If the product is active, any measures made on the active part are placed in No Show. Elements placed in No Show are taken into account in measure operation.
   Some measures kept as features are associative. In Design Mode, if you modify a part or move a part in a product structure context and the measure is impacted, it will be identified as not up-to-date in the specification tree. You can then update it locally have it updated automatically.  When measures are used to valuate parameters, an associative link between the measure and parameter is created. Measures can also be used in formulas.

Measuring Properties in a Local Axis System

An Other Axis option in the dialog box lets you measure properties in a local axis system.

This type of measure is associative: if you move the axis system, the measure is impacted and can be updated.

You will need a V5 axis system. 

1. Select the Other Axis check box in the Measure Item dialog box.

2. Select a V5 axis system in the specification tree or geometry area.

3. Make your measure.

   Measure made with respect to local axis system:

   Same measure made with respect to absolute axis system: Note: All subsequent measures are made with respect to the selected axis system.

4. To change the axis system, click the Other Axis field and select another axis system.

5. To return to the main axis system, click to clear the Other Axis check box.

6. Click OK when done.

Surfaces and Volumes

The center of gravity value result differs, depending on the command you are using (Measure Inertia or Measure Item). This is a standard behavior as:

Measure inertia takes into account the material applied on parts and/or products whereas,

Measure Item calculates the geometrical center of gravity without taking into account the applied material.

Measures and Knowledge

When performing a measure operation, Knowledge parameters are created along with the calculated values. You customize their display in the Measure customization dialog box.

Note: No knowledge parameters are created for the equation of a plane.

• Also read Using measures in knowledgeware

3D XML and Measure Item

3D XML format is now supported, which means you can:

• open and/or insert a 3D XML document containing measure item results.

• save as in 3D XML format a product containing measure item results.

Note: The text properties (i.e. Color, Font and size for the
Measure Item in 3DXML will not be retrieved when saving in 3D XML).

Important

The measure item calculation cannot be performed on arcs in approximate mode within the Section viewer under certain circumstances:

• the curve tessellation result is an arc through three points or less than three points.

• The points are aligned, similar and do not belong to the object's exact geometry.

Therefore, when measuring properties on a curve object, make sure the computed arc include more than three points (different, not aligned and resulting of the exact geometry of the considered object).

• Neither Visualization Mode nor cgr files permit selection of individual vertices.

• Associativity is not retrieved in 3D XML, when reopening the 3D XML file, the re-created measure between is broken and thus non associative. Its icon in the specification tree is the one of the non-associative measures.

• In the No Show space, Measure Item is not accessible.

• Measures performed on sheet metal features provide wrong results. In unfolded view, volume elements are not taken into account when measuring Part Bodies.

• You cannot perform measurements item within a product located in a CATAnalysis document in Product Editor workbench.

• Measures are not associative when switching between folded view and unfolded view (using the Fold/Unfold in the Sheet Metal toolbar).

• When measuring an entity with a given dimension, all geometries contained with lower dimension are ignored for the calculation. For example, edges, surfaces are ignored under a PartBody if this PartBody contains a volume (see illustration below, i.e. the difference is illustrated in Generative Shape Design and Part Design workbenches).