3-D Part Constraints Manager: Define Constraints
Overview
- General Information
- Dimensional and positional constraints
Dimensional constraints
Positional constraints
Forced fixing 
Mid-point 
Equal distance 
Equal angle 
- Context menu
General information about defining constraints
To define a constraint, the part or assembly needs to have been activated in the ICN.
In general, you should bear in mind that the Assembly HCM always regards geometries as "unbounded". This means, for example, that the distance of a point from a straight edge is measured in such a way that the perpendicular of the point is dropped on the straight line on which the line lies. This distance can differ from the distance of the point from the edge if this perpendicular does not lie on the line, as the distance from the line would then be provided by the distance from the start point or end point of the edge.
You should bear the same thing in mind when fixing an edge. This actually only fixes "the straight line on which the edge lies", i.e. the edge, even though fixed, can move along this straight line. To fix the edge completely, you must either fix both end points or the edge and an end point.
It is possible to assign distance constraints to points with a point option such as M2 (Mid-point between 2 points). Point options for different parts below sub-assemblies are also possible here.
For all constraints, it cannot be predicted easily which of the two geometries involved will be moved to fulfil them. If possible, the first selected part is transformed when a new constraint is assigned.
To define a constraint between two geometries, you define both reference geometries. Edges and surfaces can be selected directly depending on the context. In addition, the area under the cursor can be temporarily hidden by pressing the ALT key.
Once you have specified the reference geometries, the current value is displayed for distances and angles. You can adopt this value or enter a new value. Besides fixed numerical values, formulas can also be entered here.
Once the data required for a constraint has been correctly entered, HCM 3-D attempts to transform the affected parts in such a way that the constraint is fulfilled. If this attempt succeeds, the geometries are transformed accordingly. If it is not possible to fulfil the constraint because the required transformation cannot be performed due to other defined constraints, a relevant message is output.
If a corresponding constraint already exists between the two geometries, the value can be changed for distances and angles. Other constraints can be removed from the model.
