Creo Flexible Modeling > Propagating Tangency to Move, Offset, and Modify Analytic Features > About Tangency Conditions in Creo Flexible Modeling
  
About Tangency Conditions in Creo Flexible Modeling
You can set conditions on the geometry near the geometry that you modify to propagate existing tangency to Move, Offset, and Modify Analytical features. For each condition that you add, you select the geometry to which to apply the condition, and the type of condition to apply. The condition types are listed in the table below.
Condition Type
Definition
Apply to these entities
Default fixed point
Default condition, the dragged surface coincides with the system-determined point or vertex.
Points or vertices that are automatically created to maintain tangency
Undefined
Not yet defined due to undefined or invalid references.
Fixed
Fixes a surface, edge, or vertex. When applied to surfaces or surface regions, does not maintain tangency to neighboring dragged surfaces or surface regions.
Dragged surfaces and surface regions, connecting rounds, connecting chamfers
Edges and vertices that belong to dragged surfaces or surface regions
Fixed with tangency
Fixes a surface while maintaining tangency to neighboring dragged surfaces or surface regions. The tangent edge moves while the geometry is transformed.
Dragged surfaces and surface regions, connecting rounds
Fixed axis
Fixes an axis of a surface of revolution.
Dragged surfaces and surface regions of cylinders, tori, and cones
Fixed center
Fixes the center point of a sphere or torus.
Dragged surfaces and surface regions of tori and spheres
Fixed normal
Fixes the normal direction of a planar surface.
Dragged planar surfaces and surface regions
Constant R1
Keeps the radius of revolution of a torus constant.
Dragged surfaces and surface regions of tori
Constant R2
Keeps the radius of the section of a torus constant.
Dragged surfaces and surface regions of tori
Constant R
Keeps the radius of a cylinder or a sphere constant.
Dragged surfaces and surface regions of cylinders and spheres
Keep spherical
Prevents a sphere from becoming a torus, though the radius can change.
Dragged surfaces and surface regions of spheres
Constant angle
Keeps the cone angle constant.
Dragged cones and regions of cones
Fixed pole
Fixes the apex of a cone.
Dragged cones and regions of cones
Propagate through
Allows changes to a round surface and the neighboring tangent surface to keep tangency.
Round surfaces that can be propagated, including analytical surfaces like cylinders, tori, and cones
Fixed underlying edge
Fixes a point on the rounded or chamfered intersection of dragged and background surfaces. Equivalent to removing a round, and fixing the resulting edge.
Edges where the dragged surface intersects with the background geometry
Conditions also affect the following properties of an entity:
Radius—Cylinder, torus, sphere
Axis—Cylinder, torus
Angle—Cone
Normal—Plane
Center—Torus, sphere
1. Default fixed point conditions are automatically created when you propagate tangency.