Catia V5 Structure Design SR1

Ben Noble

Catia V5 Structure Design SR1

Hi there, 

I have been creating a number of structural assemblies within the CATIA structure design workbench. I have been creating beams from the grid line body skeleton part, however when I bring other parts/products to constrain to the beam sections the beams move. Do you have to constrain/anchor all structural elements (beams, endplates, plates) within a structural product even though they have been created with reference to the grid part skeleton?

I have tried using both point-to-point and on line body methods when creating beams with the same result. Beams are not fixed.

Any pointers or best practices when using this SR1 would be appreciated..

 

V5-6 2013 R23

 

 

Timothy John Suhr

RE: Catia V5 Structure Design SR1
(in response to Ben Noble)

Ben,
The first thing to remember is the first part selected will move unless part 1 has more constrates that part 2.  The thing that needs a fix is the skeleton model.  You really do want the model moving around. 
If the assembly has multiple sub-assemblies, first apply constraints to the parts under the sub-assembly.  Note that a Fixed Constraint can be used in the sub-assembly to ensure the parts won’t move in different or multiple directions. The Fixed Constraint will not affect the upper level assemblies. Make sure to activate the sub-assembly to apply constraints, as CATIA will not automatically apply the constraints to the sub-assembly.
If the assembly structure has multiple parts but no sub-assemblies, apply a Fixed Constraint to the part that is not intended to move (i.e. skeleton model). Then apply other constraints from the moving part(s) to the fixed part. The fixed constraint is just to ensure the primary part remains stationary.
Whenever constraints are being applied, the user can “build” the assembly by using   Update All. This will verify that the direction is correct, or if the constraint is correct for the scenario. Then use the Undo button to undo the constraint on the part(s).
A rigid product (CATIA default) is an assembly of parts that, in terms of building the assembly with constraints, will use the assembly as a whole. If the sub-assembly has constraints, those constraints will act as normal but the upper level constraints will apply to the entire sub-assembly.
A flexible product is an assembly of parts that, in terms of building the assembly with constraints, will use the individual parts under the sub-assembly. Parts under a flexible assembly still require constraints to be built under the required sub-assembly.
If the sub-assembly has constraints, those constraints will act as normal but the upper level constraints will apply to the individual parts and build accordingly with Degrees of Freedom. To switch the product from a rigid assembly to a flexible assembly, right-click on the assembly and highlight the Product1 object and select.
Publishing geometrical elements is the process of making geometrical features available to different users. This operation is very useful when working in assembly design context.  This process provides a greater level of constraint usability than to unpublished elements.
The Constraints Analysis dialog box that appears displays all the information you need. The Constraints tab contains a detailed status of the assembly: the number of non-constrained components and the status of the defined constraints.

Timothy J. Suhr

Electro-Mechanical Engineering (EME) Product Committee Co-Chair

2015 COE BJ Fries Award of Merit Recipient

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Ben Noble

RE: Catia V5 Structure Design SR1
(in response to Timothy John Suhr)

Hi Timothy, 

Thanks for your comprehensive reply. You are right constraining the skeleton with the fix constraint ensures everything stays put. I had assumed when using the grid feature to create the skeleton that it would automatically fix its self but this is not the case, and I can see why now. 

In future I will always constrain the skeleton using the fix command before I create any other structural beams or plates

Thanks,

Ben

Leszek Zalewski

RE: Catia V5 Structure Design SR1
(in response to Ben Noble)

Hi Ben, 

Try this: https://www.youtube.com/watch?v=tcZ8MgQLD40