Modellazione Diretta Variazionale
Use geometric constraints (aka variational direct modeling) to model parametric solids and surfaces. Define constraints between elements (edges and faces) to modify solid and surface models.
As soon as a constraint is added BricsCAD automatically modifies the model and these constraints are updated with subsequent modifications to the model. The key advantage of variational direct modeling is that all constraints are taken into account simultaneously and the model behavior does not depend on the constraint creation order. It allows you to parameterize any feature of the 3D model without the worry of model creation history.
I Vincoli dimensionali permettono di controllare le dimensioni del modello, durante l'introduzione del vincolo o la modifica del valore del suo parametro, BricsCAD aggiorna automaticamente la geometria solida per soddisfare il vincolo. Ad esempio, le dimensioni di una scatola possono essere controllate dai parametri di tre vincoli di distanza applicati alle sue faccie opposte.
I vincoli possono essere creati usando la barra degli strumenti Vincoli 3D, il menu Parametrico/Vincoli 3D o il gruppo di comandi Vincoli nel Quad.
BricsCAD fornisce i seguenti vincoli 3D:
Geometrical constraints: Fix (), Coincident (), Concentric (), Parallel (), Perpendicular (), Tangent (), and Rigid Set().
Dimensional 3D constraints: Distance () , Radius (), Angle (), Cone Angle (), Path Constraint ().
The Mechanical Browser
Tipi di Vincoli 3D
The following entities are supported for constraint creation:
Facce di solidi 3D e superfici di geometria planare, cilindrica, sferica, toroidale e conica.
Curve 3D e spigoli di solidi e superfici 3D
Lines, rays, xlines, circles and arcs.
Arbitrary curves for coincident and path constraints with a point as another argument.
Piani, assi e punti di origine di un sistema di coordinate del blocco o globale.
3D constraints have a number of properties that allow you to control how BricsCAD treats them in various situations. For full description see the 3D Constraints Properties page.
Dimensional 3D constraints can also be geometry-driven. They update the model to accurately reflect the current state of the model. You can not specify their expression. Instead, their value is obtained from the model and can be changed with direct modeling operations and changes to other constraints.
Other parameters, including constraints, can depend on the values of geometry-driven constraints. In some circumstances a constraint dependent on geometry-driven constraints can make the model unresolvable. This should be avoided.
Turn regular constraints to geometry-driven constraints and vice versa, with the Mechanical Browser, Parameters Manager or DMCONSTRAINT3D command. After a regular constraint is turned into a geometry-driven one, its expression will be overwritten with the first modification of the model that affects this constraint.
Vincoli 3D e Modellazione Diretta
3D Constraints are taken into account when direct modeling operations are applied. If there is a 3D constraint that fixes the placement of faces or edges this constraint will be preserved during Push/Pull, Move and Rotate operations. A 3D constraint can be temporarily disabled, or erased permanently, with the Mechanical Browser Constraints section.
Geometry-driven constraints will update their values when a direct modeling operation is completed. This can lead to additional charges to the model.
If some faces or edges disappear, during a direct modeling or in Boolean solid editing operation, 3D constraints applied to such entities are removed. However, if there is an exact correspondence between the initial faces and the faces obtained, 3D constraints are automatically applied to the new entities.
Dependant on the value of the DMRECOGNIZE system variable, BricsCAD will automatically recognize geometrical relations between the surfaces of a solid and will preserve them during direct modeling operations (see Design Intent Recognition).