Measure Features, Feature Relations and Datum Analysis Features Ron Thellen Johns Hopkins University Applied Physics Laboratory

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Topics of Discussion Measure Features Distance Angle Area Feature Relations and Feature Parameters UDA (User Defined Analysis) Construction Groups Field Datum Points Sensitivity Studies

Review Two Case Studies Surface Area Analysis Measure Features Feature Relations/Parameters Sensitivity Analysis Field of View Study UDAs Field Datum Points Construction Groups

Surface Area Analysis Problem Analyze the change in area of multiple surfaces as the shape of the model changes. Graphically capture the resulting changes to the model. Pass the results to Excel for further study.

Surface Area Analysis Initial Conditions Given a column of material containing spherical cavities Monitor surface area of Flat green surface Red spherical cavity Blue spherical cavity Additional cavities…

Surface Area Analysis Further Conditions As column height decreases Green plane contacts red sphere At that point the red sphere begins increasing in size Eventually the red sphere contacts the blue sphere At that point the blue sphere begins increasing in size

Surface Area Analysis Start the Model DTM1 is offset from TOP DTM2 is offset from DTM1 Extrude 1 is sketched on TOP and extruded to DTM2

Surface Area Analysis Build 1st Sphere Sketch Datum Curve for initial sphere size Create CS0 at top of curve Used to measure flat green surface location relative to initial sphere size and location Create Distance Measure Feature Create spherical cut Do not use sketched datum curve above Group features

Surface Area Analysis Build Additional Spheres Repeat steps in previous slide For each sphere’s Distance Measure Feature Measure from its grouped CSYS to the sphere above

Surface Area Analysis Create Area Measures Create Area Measure Features for Flat green plane Red sphere Blue sphere Yellow sphere Create Annotation to display measure results

Measure Features An Overview Analysis  Measure … Common to all… Distance Angle Area Common to all… Select features to measure Select type of measure (Quick, Saved or Feature) Assign name (for Saved and Feature) For Feature types Regenerate status and optional Feature Parameters and Datum Features

Measure Features Distance Example Select measure entities From – To Returns distance Select optional projection reference Returns dx, dy, dz in addition to distance Change type from Quick to Feature Assign appropriate name

Measure Features Distance Example (cont.) Select Feature tab Select Regenerate type Always, Read Only, Design Study Select optional feature parameters to create DISTANCE_Y is of interest in this case Select optional datum features to create

Feature Relations and Parameters Tools  Relations (includes parameters) or… Tools  Parameters Relations and Parameters can apply to Part (default) Feature Other…

Feature Parameters Change “Look In” from Part to Feature Select the Feature in Model Tree or… In model Select Add Parameter Assign Name and Value to the Parameter This is only an example. It is not used in this study. As shown earlier, Feature Parameters can also be created as part of a Measure Feature

Feature Relations Change “Look In” from Part to Feature Select the Feature in Model Tree or… In model Enter relation This Feature Relation is what causes the sphere radius to increase Create an equivalent relation for each sphere

Relation in Detail What does it say? distance_y FID_ is the Feature Parameter created while defining the Measure Feature FID_ Feature ID DTM2_TO_CS0_DISTANCE The name of the Measure Feature

Relation in Detail But what does it say? If the feature parameter named “distance_y”, in the (:) feature with the id (FID_) named “DTM2_TO_CS0_DISTANCE” is less than (<) 0 Dimension d14 is assigned the value of the Part parameter named “pore_start_radius” minus the value of the feature parameter named…

Feature Relations Shortcut In the Relations editor enter the starting text Press the Insert Parameter Name from List button

Feature Relations Shortcut (cont.) In the Relations editor enter the starting text Press the Insert Parameter Name from List button In the Select Parameter dialog, change to Feature and select the Measure Feature in the model tree

Feature Relations Shortcut (cont.) In the Relations editor enter the starting text Press the Insert Parameter Name from List button In the Select Parameter dialog, change to Feature and select the Measure Feature in the model tree Select the parameter and press Insert Selected The feature parameter is added to the relation

Surface Area Analysis Back to the Model We could edit the offset value of DTM2 manually to exercise our model… but where’s the fun in that?

Sensitivity Analysis Analysis  Sensitivity Analysis… Used to examine how sensitive your model is to dimensional changes Some initial setup options Preferences Animate Model (Yes!) Default range Set’s the default range for selected dimension you will adjust (I usually skip this and adjust the range manually)

Sensitivity Analysis The Dialog Set Options Assign Study Name Select Variable Dimension DTM2 offset dim Set Variable Range Select Parameter to plot One of the Area Measure Feature parameters Set the # of Steps More steps = finer analysis Compute

Sensitivity Analysis The Displayed Results

Sensitivity Analysis The Graphed Results ??? SPR 1450730

Sensitivity Analysis The Graphed Results (cont.) 2 3 1 2 3 4 1 ??? 4

Surface Area Analysis Summary Utilized… Measure Features Feature Relations/Parameters Sensitivity Analysis Analyzed the change in area of multiple surfaces as the shape of the model changed. Graphically captured the resulting changes to the model. Passed the results to Excel for further study.

Review Two Case Studies Surface Area Analysis Measure Features Feature Relations/Parameters Sensitivity Analysis Field of View Study Construction Groups Field Datum Points UDAs

Field of View Study Problem Determine the reduction in a field of view that is caused by an obstruction Determine % reduction in the field of view

Field of View Study Assumption Field of View origin is a point

Pro/PHOTORENDER Analogy Field of View origin = Point light source Obstructed volume = Shadow cast by obstruction

Field of View Study Create Field of View Model Half sphere in this example Assemble into assembly where we will view the results of the study Assign appropriate references Csys to csys in this example (focal point)

Field of View Study Create Area Measure Feature In order to determine % reduction in Field of View Create an Area Measure before we create features that will cut out the obstructed volume (Analysis  Measure  Area)

Field of View Study Create Additional Construction Geometry Used for subsequent feature creation Focal Point Axis of Rotation Projection Plane (offset from sphere surface)

Field of View Study Copy Obstruction Geometry Insert  Shared Data  Copy Geometry… Only the surface quilt of one part was selected (in this case)

Field of View Study Intersect Copied Geometry Create Datum Plane Through Axis of Rotation Offset (at an angle) from existing plane (FRONT)

Field of View Study Intersect Copied Geometry (cont.) Create Datum Plane Through Axis of Rotation Offset (at an angle) from existing plane (FRONT) Intersect Datum Plane with Copied Geometry Edit  Intersect…

Construction Group A Construction Group… Includes geometry features (usually Datum Features) Can include a Field Datum Point Must include an Analysis Feature (and it must be the last feature in a Construction Group, otherwise it is just a Group) Used by User Defined Analysis (UDA) If the first feature is a Field Datum Point, the Analysis Feature measure can be solved across the entire length of the curve or over the entire surface it is created on (the domain)

Construction Group (cont.) Do not use the features in a Construction Group for subsequent modeling activities After creating the Construction Group, suppress it It will still be selectable for UDA purposes

Field Datum Point Insert  Model Datum  Point  Field… or A Field Datum Point… Is a dimensionless Datum Point Exists within the domain of a Datum Curve Surface

Field of View Study Field Datum Point (for Construction Group) Create the Field Datum Point on the intersect curve created previously

Field of View Study Datum Axis (for Construction Group) Create a Datum Curve from the Focal Point to the Field Datum Point

Field of View Study Measure Angle Feature (for Constr. Group) Create a Measure Angle Feature to measure the angle between the Axis of Rotation and the Datum Axis just created. Use the Datum Plane previously created as your projection plane.

Viewed looking at DTM1 (the projection reference) Field of View Study Measure Angle Feature (cont.) Pay close attention to the blue measure arrows. Use the yellow flip arrows if necessary. Set Plot range to +/-180 Viewed looking at DTM1 (the projection reference)

Field of View Study Measure Angle Feature (cont.) Create the PROJ_ANGLE parameter Set Regenerate to Always

Field of View Study Create the Construction Group Select the features to include in the Construction Group Group the features Suppress the Group

User Defined Analysis (UDA) A UDA is a specific type of Datum Analysis Feature Insert  Model Datum  Analysis… or Used to create measures or analyses beyond those available in the Analysis menu

Field of View Study Create the UDA Step through the analysis elements Name Type Regen Request

Field of View Study Create the UDA (cont.) Step through the analysis elements Name Type Regen Request Definition Select Type (Construction Group) Select Parameter and Domain Compute

Field of View Study Create the UDA (cont.) Step through the analysis elements Name Type Regen Request Definition

Field of View Study Create the UDA (cont.) Step through the analysis elements Name Type Regen Request Definition Result Params

Field of View Study Create the UDA (cont.) Step through the analysis elements Name Type Regen Request Definition Result Params Result Datums

UDA Wrap-Up Uses a Construction Group When the UDA regenerates Field Datum Point Datum Axis Angle Measure Feature When the UDA regenerates Field Datum Point traverses the Datum Curve (domain) it is placed on from beginning to end The Angle Measure is calculated at every position of the Field Datum Point A Datum Point is created at the maximum measured angle

Maximum measured angle found! UDA Wrap-Up (cont.) Maximum measured angle found!

Field of View Study Create Another Datum Axis Through the… Focal Point UDA_MAX_PNT This point goes through the focal point and is tangent to the obstruction geometry surface

Field of View Study Create an Intersect Datum Point Using the… Datum Axis just created PROJ_PLANE created earlier

Progress So Far We have created… Intersect Datum Curve Field Datum Point on that curve Axis from the Focal Point to the Field Datum Point Angle measure from Axis of Rotation to that axis A UDA with a datum point at the max measured angle A “tangent” axis through the Focal Point and max point A datum point on the projection plane by intersecting the tangent axis with the projection plane

What’s Next? Repeat the Indicated Geometry Creation The initial Datum Plane in each group of features will have its angular offset measured from the previous Datum Plane

What’s Next? (cont.) How Many Times Do You Repeat? The purpose of each group is to create two datum points At the max angle on the obstruction geometry surface On the projection plane Each set of points will be used to create A datum curve on the obstruction geometry A datum curve on the projection plane (a shadow) A greater number of points will create more accurate datum curves – you decide!

Field of View Study Result of Repeated Geometry Creation

Field of View Study Create Datum Curves Through “max” points Through projected points

Field of View Study Create Boundary Blend Through projected datum curve Through “max” curve Through Focal Point

Field of View Study Remove Material from Field of View Select Boundary Blend Edit  Solidify

Field of View Study Create 2nd Area Measure Feature In order to determine % reduction in Field of View Create a 2nd Area Measure after we cut out the obstructed volume (Analysis  Measure  Area)

Field of View Study Create a Part Relation to Calculate the % Reduction in Surface Area

Resulting Field of View Geometry

Field of View Study Summary Utilized… Measure Features Construction Groups Field Datum Points UDAs Determined the reduction in a field of view caused by an obstruction Determined % reduction in the field of view

Questions?