| Power Tools - Easy Access to Information with Evaluate Features
What is an Evaluate Feature? They are certainly a less common feature, but they provide some
neat capability. Creating an Evaluate Feature is like making a "permanent" measurement within the Pro/E model.
In the simplest terms, an Evaluate Feature is like having a caliper on some part of your model so when you need
the info, you just look at the dial. Figure 1 shows a part of the Feature Information window
displaying the Measurements of an Evaluate Feature.
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| Figure 1 |
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Primary uses include: 1. Easy access to measurement information, and 2. The ability to
use model measurements in relations to drive other features.
1. Easy access to measurement information:
- Have you ever built a model that had to meet some particular dimensional criteria that couldn't be easily
controlled by a dimension? When working with the model you measured, modified, then measured again?
You don't need to keep measuring the same thing over and over. Use an Evaluate Feature to do the measuring for you.
Here are a couple of classic examples:
- You make a draft and you need to know the min or max wall thickness. The wall height changes or
the draft angle changes and you need to measure again.
- Two parts in an assembly need to come close to each other, but can't touch. As the design progresses,
you continually measure again the distance between the two parts.
- You need to know a distance or thickness of an area that is later removed by a cut or round. Make
the Evaluate Feature earlier in the model and you will always have that dimension value even when you can't measure
it in the model anymore. (See the rib of Figure 4.)
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| Figure 2 |
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Once an Evaluate Feature is created, you can post the value in the model tree using a parameter as shown in
Figure 2.
To put a measurement value in the Model Tree, first create a parameter and assign it the value of the
measurement. Next, assign the parameter to a model tree column using VIEW > MODEL TREE SETUP >
COLUMN DISPLAY. Then under TYPE, choose MODEL PARAMS and find the parameter you just
created in the relations -- this is parameter "SIDE" in the example of Figures 2 & 3.
Figure 3 shows relations created with measurements. The 3rd relation (which creates the parameter)
must be created prior to the model tree display. Figure 2 shows the display of the "SIDE"
parameter value in the model tree. The method is sort of cumbersome, but it works.
2. Using model measurements to drive feature relations:
So, How do you make an Evaluate Feature?
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| Figure 4 |
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Here are the instructions from Pro/Help. Other than the "How to's", Help is useless so you'll have
to experiment to really learn the power.
Note: The Evaluate option on the DATUM menu is ONLY available when the
configuration file option "allow_anatomic_features" is set to "yes". (Why does PTC bury these things?)
- Choose INSERT > DATUM > EVALUATE from the top drop-down menus.
- Enter a name for the Evaluate Feature. (This will appear in the model tree.)
- The system displays the MEASURE PARAM menu with the following options:
- Create - Create and name a measurement parameter. When you name the measurement, the system displays the GET MEASURE menu. The options are as follows:
- Edg/Crv Len - Measure an edge or a curve length.
- Edg/Crv Curv - Measure the curvature of an edge or curve at a point on the edge or curve.
- Angle - Measure the angle between two selected planes, axes, planar edges, or curves.
- Distance - Measure the distance between any combination of two points, vertices, planes, axes, or coordinate systems.
- Area - Measure a surface or quilt area.
- Diameter - Measure the surface diameter of any revolved surface of a part.
- Min Radius - Measure the minimum radius of any revolved surface. The system places a red circle or cross hair marker temporarily at the minimum radius.
- Srf Clearance - Measure clearance between two surfaces.
- Delete - Delete an existing measurement parameter.
- Redo - Redefine a measurement parameter.
- Info - Display measurement information for all the parameters.
- Show - Highlight the references of the selected measurement parameters.
- Choose Create from the MEASURE PARAM menu and name the measurement parameter.
- Choose the GET MEASURE option.
- When you have made all the desired measurements, choose DONE from the MEASURE PARAM menu.
You can have several measurements in the same Evaluate Feature -- Figure 1 shows 2.
To see the measurements, use Info > Feature and select the Evaluate Feature. The display will be
similar to Figure 1.
Using Evaluate Feature measurements in Relations:
In relations, the Evaluate Feature can be used to drive dimensions in model features and in assemblies.
Use one of the following formats to access measurement values in relations:
- measurement_name:fid_N
- ... or ...
- measurement_name:fid_feature_name
In these formats, measurement_name is the name of the measurement within the Evaluate Feature, N is
the internal feature identifier number (obtained by using Info), and feature_name is the name of the Evaluate
Feature. ... and YES, the "FID_" must be typed.
An example of the syntax used in a relation is in Figure 3.
One other IMPORTANT NOTE: For values to appear correctly on the model
tree and for relations to work correctly, the model will often have to be regenerated twice. Remember that Pro/E
evaluates parameters and relations at the beginning of regeneration, so these values will be based on the
geometry prior to regeneration. After regeneration, the values in the Evaluate Feature will be up-to-date, but
the relations will be behind. You will often get messages like Figure 5 indicating that the model must
be regenerated again. Just hit REGENERATE again, and all will be well. Also, if you have regen
failure that may be caused by the non-updating values, try FIX MODEL > REGENERATE first. That
will often take care of the problem.
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| Figure 5 - Error message means "Regenerate again" |
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Good luck using the Evaluate Features. They can certainly be a great tool. If you have
trouble finding information, call PTC Tech Support (1 800 4 PRO HEL -- No Kidding).
BTW, if you have Behavior Modeler, an Analysis Feature will do this and much more. It can
also be displayed in the model tree in a more user friendly fashion. Again, consult HELP and Tech support
for more info.
See you next month!
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