About Connect Checker Analysis

You can use the Connect Checker Analysis command to analyze the connections between curves, between surfaces and between curves and surfaces. You can analyze the connection and continuity type, implicitly or explicitly, based on threshold values and constraints you can specify.

This section explains the various connect checker types between two curves and/or surfaces.

This page discusses:

See Also
Connect Checker Analysis Dialog Box
Checking Connections Between Curves
Checking Connections Between Surfaces

Connection Types

You can check and analyze the connections between wireframe elements using the available connection types.

The Connect Checker Analysis command can analyze the following types of elements.

Filter according to the wireframe element types:

  • Curve-Curve.
  • Surface-Surface.
  • Surface-Curve.

Filter according to the connection mode between the wireframe elements:

  • Boundary.
  • Projection.

Five Connect Checker Analysis connection types can be made from the following filter combination:

  • Curve-Curve + Boundary: analysis between a curve extremity with another curve extremity.
  • Curve-Curve + Projection: analysis between a curve extremity with its projection on another curve.
  • Surface-Surface + Boundary: analysis between a surface border with another surface border.
  • Surface-Surface + Projection: analysis between a surface border with its projection on another surface.
  • Surface-Curve + Projection: analysis between a curve extremity with its projection on a surface.

About Connection

To get a connection between two input elements, the gap between those two elements must be less than or equal to the maximum gap, otherwise the connection is not analyzed.

The Connect Checker Analysis command measures the gap of all the connections between all the borders of the geometrical elements, irrespective of the size of the geometrical elements.

Warning: There may be instances (such as very small elements or a very large maximum gap) where the system finds connections which are unexpected. In these instances, adjust the value of Maximum Gap until the unexpected connections are eliminated.

Note: Connection analysis of one element with two different elements will have different deviation results as the topology of these elements is different. The connection analysis follows a different algorithm to measure the gap.

Consider connection analysis of one element A with two different elements B and C.

  • If the connection of A and B at Maximum Gap is 10mm, it is not necessary that the connection between A and C will also be detected with the same maximum gap.
  • If connection between element A and C has a maximum gap of 20 mm, it is not necessary that deviation results (specifically G0 results) will be greater than the results of connection between A and B elements.

Consider a case where two elements say A and B at connection have the maximum gap as 10mm with G0 value 6.5mm. Now if the maximum gap value is increased to 15 mm, the second found connection between A and B can have G0 value as 7.6 mm.

About Display

When the display filter corresponding to the selected analysis is set, to display the results between the input elements in the work area, the computed analysis value between these two elements must be greater than or equal to the minimum value and less or equal to the maximum value of the Display filter frame of the current analysis.

About Migration

A warning migration message is displayed if an old connect checker analysis (with a previous data model) is read. Results after migration may differ as the Minimum gap value does not longer affect G1, G2, and G3 analysis.

Internal and External Connections

The elements you check can be isolated from each other or can be joined.

There are two connection analysis scenarios possible:

  • The surfaces are isolated from each other:

    Only geometrical connections are checked (all pairs of neighboring surface edges within the tolerance given by the minimum G0 value and the maximum gap).

  • The surfaces are joined (using a matching command):
    • If Internal Edge is not selected in the Connection area, only the external connections are searched, i.e. the connections along free surface borders or at free curve extremities.
    • If Internal Edge is selected, in addition to the external connections, the internal connections are also searched, i.e. the connections along internal edge or at internal vertex.

Continuity Types

You can check and analyze the continuity of connections between the selected elements.

The following continuity types can be analyzed:

  • G0: Analyzes the continuity in point.
  • G1: Analyzes the continuity in tangency.
    Note: For Curve-Curve, the angle value which is displayed is the angle between the two tangent of the curves at their extremities. This angle does not depend on the curve orientations.
  • G2: Analyzes the continuity in curvature.
  • G3: Analyzes the continuity in curvature tangency.
  • Overlap Defect: Analyzes overlap defect.

Threshold Value

The threshold values define the maximum limits for continuity.

The connection between the elements is considered as being continuous at the following threshold values:

  • G0: The geometrical resolution (usually equal to 0.001 mm).
  • G1: 0.01 deg.
  • G2: 2 %.
  • G3: 0.1 deg.

Implicit Mode

No selection is made in the Type area of the Connect Checker dialog box.

In this mode, only the following analyses can be made:

  • Analysis between surfaces borders.
  • Analysis between curves extremities.
  • Analysis between a curve extremity and its projection on a surface.

Explicit Mode

A selection is made in the Type area of the Connect Checker dialog box.

Memory Usage

A warning message is displayed during Connect Checker analysis as soon as the current memory use in a session exceeds a limit.

This limit is customizable in the Memory Warning section under Me > Preferences > Common Preferences > General > Cache and Performance > General

Matching Constraint for Analysis

The parent matching constraint node and individual matching constraints can be selected for the Connect Checker Analysis command.

Depending on the connection mode (Surface-Surface/Curve-Curve/Surface-Curve) the match constraints from the matching parent node (between surface boundaries/curve extremities) are filtered as inputs for Connect Checker. The matching constraint created in the following cases is not selected for analysis:

  • between the edge of surface and curve,
  • between curve vertex and plane,
  • between curve vertex and vertex in 3D.

In such cases the matching constraint is not selectable and the forbidden sign is displayed along with the tool tip:

Some of the Match Constraints cannot be selected as input because the type of connection 
generated by them is not supported by Connect Checker.

Notes:
  • When a single match constraint is given as input, the elements constrained by it are considered for analysis.
  • When the match constraint is given as input along with other input elements or other match constraints, all the input elements of match constraint are considered for analysis.
  • An internal edge does not influence the connection analysis with match constraint inputs in connect checker.