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Shade a surface with its draft angles
Judge or evaluate curve or surface quality
Prepare a model for import into CAD systems
Check objects for modeling problems
The Check
model tool lists possible problems with your model that can affect
data transfer to other software packages.
Show a list of modeling
problems
- Choose Evaluate > Check Model ❒.
In
the Check Model Options window:
- Choose whether to check only Surfaces,
only Curves or Both.
- Choose whether to check All objects, All
Visible objects, or the picked (Active)
objects.
- Choose whether to list only objects with
problems (Only Errors) or all objects.
- Choose a set of construction tolerances
from the Use Construction Preset drop
down menu, to use in the model check calculations.
NoteThese correspond
to the
Construction Presets available
from
Preferences > Construction Options.
Select
Use Current Tolerances to use
whatever preset is already selected in the
Construction
Options window (indicated by a white arrow).
- Choose what types of problems or conditions
you want to check for. See Evaluate > Check Model for more information on
the different checks.
NoteA special section called Product
Data Quality contains checks that apply specifically
to making a model compliant with the VDA-4955 and SASIG PDQ guidelines,
so that it can be better handled by other packages such as Unigraphics,
Catia, Pro/E, and so on.
See Prepare
a model for import into CAD systems for more information.
- Click Check.
The resulting check data
is displayed in a window organized as a table. Geometry that fails
a given check will display a mark in the corresponding column.
See View the data in the report window
Check for duplicate curves
or surfaces
You can check for both
copies (exact duplicates), and duplicates within a given tolerance.
Copies have the same CVs, same knots, and same degree (such as geometry created
with Edit > Copy and Edit
> Paste).
Checking for copies
This is the fastest of
the two methods.
- Set Duplicate Geometry to Copies in
the Check Model Settings option window.
- Click Check.
The report window displays
a column titled Copies to help
you identify all the copies. If Report is
set to All, the original geometry
is identified by the word “Original” in the column.
Checking for duplicates
within a given tolerance
- Set Duplicate Geometry to Duplicate
Within Tolerance in the Check Model Settings option window.
- Adjust the Duplicate Tolerance value.
Geometry that is a duplicate of, or embedded into other geometry
within this tolerance will be reported.
- Click Check.
The
report window displays two columns titled Embedded In and Tolerance Duplicates to help
you identify all the duplicates. The duplicates prefixed by “0”
in the Tolerance Duplicates column are considered the originals.
Check continuity between
curves or surfaces
- Turn on the Max. Gap Distance - G0, Tangent
Angle - G1 or Curvature - G2 option
in the Check Model Options window.
NoteTolerances
for these continuity checks are found in the
Tolerance:Continuity section
of
Preferences > Construction Options and correspond to the construction preset
selected in the
Check Model Options window.
NoteFor
the G0 test to be successful, you must also ensure that the
Topology
Distance tolerance (
Tolerances:Topology section
under
Preferences > Construction Options ) is larger than the
Maximum
Gap Distance.
- Click Check.
The report
window displays columns titled G0, G1 and G2 with
marks indicating failure. If geometry fails the G0 test, higher
continuity tests for G1 and G2 will not be performed. Similarly,
if geometry fails the G1 test, continuity test for G2 will not be
performed
In
the viewing window, the boundaries that failed the continuity tests
are shown as thick yellow lines with a letter identifying the type
of discontinuity (P = positional, T = tangent, C = curvature).
What do Report Parameters
do?
The report parameters
are tolerance values above which certain types of checks will not
be executed.
- Tangent Angle Maximum:
tangent angle value above which geometry will not be included in
the G1 continuity check.
- Curvature Maximum:
curvature deviation value above which geometry will not be included
in the G2 continuity test.
Check consistency of orientation
of surface normals
- Turn on the Normal Consistency option in
the Check Model Options window.
-
NoteThe
Topology
Distance tolerance is used to determine which surfaces
are topologically adjacent and should have their normals checked
as a group. It is found in the
Tolerances:Topology section
of
Preferences > Construction Options and corresponds to the construction preset
selected in the
Check Model Options window.
- Click Check.
The report window displays
a column titled Flipped Normal to help
you identify the surfaces with inconsistent normal directions. In
the viewing window, the inconsistent normals are shown as white
arrows.
Check for maximum degree
This
check enables you to identify curves and surfaces that exceed a
user-defined degree. The default value for maximum degree is 7.
- In the Check Model Settings option window,
set the Check option to Surfaces, Curves or Both.
- Turn on the Maximum Degree option.
- Adjust the value in the text field next
to the option selection box. Curves and/or surfaces that have degree
larger than this value will be reported.
- Click Check.
The report window displays
a column titled Degree which contains the degree
of curves and/or surfaces that failed the test.
Check for minimum radius
of curvature
This check enable you to identify
surfaces (including trimmed surfaces) that exceed a user-defined
curvature radius.
- Turn on the Minimum Radius of Curvature option in
the Check Model Settings option window.
- Adjust the tolerance value in the text
field next to the option check box. Surfaces that have a radius
of curvature smaller than this value (in any direction) will be
reported.
- Click Check.
The report window displays
a column titled Min Radius of Curv which contains
the minimum radius found on surfaces that failed the test.
Check for surface or planar
curve waviness
This
check enables you to identify surfaces or planar curves that have
more than a certain number of inflections (change in curvature sign)
per span (1 is the default) or over their entire length or width
(3 is the default).
- Turn on the Surface or Planar Curve
Waviness option in the Check Model Settings option window.
- Specify your criteria for waviness by
changing the value next to the checkbox. This value represents the
total number of inflections allowed over the length (or width) of
the planar curve or surface for it to pass the test.
- If the Allowed Inflections
Per Span option is turned on, you can adjust the corresponding
value to add an extra waviness criterion. The check will fail if
the planar curve or surface has more than the given number of inflections
per span, or more than the given number of inflections overall (as
specified in step 2).
- Click Check.
The report window displays
a column titled Waviness with marks indicating
failure.
Check for short edges
This check enables you
to identify curves and surface boundaries that are shorter than
a user-defined value. This helps find geometry that may be problematic
when used in certain operations, or may not be recognized as valid
geometry in downstream CAD systems.
See Prepare
a model for import into CAD systems for more information.
- In the Check Model Settings option window,
set the Check option to Surfaces, Curves or Both.
- Verify that the Short
Edges option is turned on.
- Adjust the value in the text field next
to the option selection box. Curves that are shorter than this value
and/or surface that have boundaries shorter than this value will
be reported.
- Click Check.
The report window displays
a column titled Short Edges which contains
the number of short edges on geometry that failed the test.
Check for non-planar curves
This
check enables you to identify curves that are not planar. In the
Check Model Settings option window, set the Check option
to Curves or Both.
- Turn on the Non-Planar Curves option.
- Click Check.
The report window displays
a column titled Non-Planar Curve with marks
indicating failure for the objects listed in the left-hand column.
Check for indistinct knots
or tiny spans
This check enables you to identify curves and surfaces
whose interior span/isoparm configuration (distance between adjacent
isoparametric curves) results in knots being too close (indistinct
knots), or in the segment or patch size being too small (tiny spans).
The indistinct knot criterion
is violated if two adjacent knots are non-multiple (not exactly
equal), but within a user supplied tolerance in the curve or surface
parameter space.
NoteMultiple
knots do not violate this criterion - a separate check already exists
for finding curves and surfaces with multiple knots.
The tiny span criterion
for the minimal size of NURBS segments is violated if the segment
length (or the length of both opposing patch segments for surfaces)
is smaller than a user supplied distance tolerance.
- Turn on the Indistinct Knots and/or
the Tiny Spans option.
- Adjust the value in the field next to
the option selection box.
NoteFor Indistinct Knots,
the value is a tolerance in parameter space. For Tiny
Spans, the value is a distance expressed in current linear
units (for example mm).
- Click Check.
The report window displays
columns titled Indistinct Knots and Tiny
Spans which contain the number of occurences of indistinct
knots and tiny spans respectively, in the geometry that failed the
test.
Check for maximum number
of spans
This check enables you to identify curves
and surfaces that contain a number of spans exceeding a user-defined
value.
- Turn on the Maximum Spans option.
- Adjust the value in the text field next
to the option selection box. Curves and surfaces that exceed this
number of spans will be reported.
NoteSurfaces will fail
the check if the number of spans in either the U or V direction
exceeds the given value.
- Click Check.
The report window displays
a column titled Spans which contains the number
of spans in the geometry that failed the test.
Check for self-intersections
This check enables you to identify
curves, surface boundaries, or trimmed surface boundaries that contain
interior self-intersections. A self-intersection refers to the curve
or surface boundary intersecting itself at one or more locations
that are not both endpoints (see pictures below).
- Turn on the Curve or Surf-Boundary
Self Intersect option.
- Click Check.
The report window displays
a column titled Self-Intersecting with marks
indicating failure for the objects listed in the left-hand column.
Check for intersection
of trim boundaries
This check enables you to identify
trimmed surfaces containing boundaries that intersect other boundaries
on the same surface, within a user-defined tolerance (see picture).
- Turn on the Trimmed-Surf Boundary
Intersect option.
- Adjust the value in the text field next
to the option selection box. Boundaries that intersect within this
distance will be reported.
- Click Check.
The report window displays
a column titled Trim Bndy Intersect with marks
indicating failure for the objects listed in the left-hand column.
View the data in the report
window
- Click the column heading to sort by a
column. To reverse the sort, click the column heading again. You
can also select the column’s name from the Sort menu.
- Hold the on a row to highlight the
object in the view windows.
- Click to select a row, hold to select multiple lines.
- To pick the objects corresponding to
the selected rows, open the window’s Pick menu
and choose Pick Selected.
- To pick all copies, open the window’s Pick menu
and choose Pick Copies. This leaves the
original copy unselected for each set of duplicates. (This menu
item only appears if Copies was turned on in the
option window.)
- To pick all duplicate objects within
tolerance, open the window’s Pick menu
and choose Pick Tolerance Duplicates.
This leaves one single copy unselected for each set of duplicates.
(This menu item only appears if Duplicates Within Tolerance was
turned on in the option window.)
- To export the data to a text file, open
the window’s File menu and choose Export Text.
NoteTo
import the text file into a spreadsheet program, choose “|” (vertical
bar) as the column separator.