Stampable, turnable and drillable surfaces

Couple design nodes in such a way that a stampable, turnable or drillable surface is maintained.

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LINK_SHAPE

CLIENT / Applicable for Controller (SHAPE_CONTROLLER) Sensitivity (SHAPE_SENSITIVITY)
SURF_STAMP OK -
SURF_TURN OK -
SURF_DRILL OK -

Stampable surface (SURF_STAMP)

Maintaining a stampable surface during optimization involves defining a stamping direction. The stamping domain is defined using a node group. The direction defined by the CLIENT_DIR parameter specifies the stamping direction.The link condition is defined using the following parameters: 

        
          CLIENT = SURF_STAMP
          CLIENT_DIR = <x_1>,<x_2>,<x_3>
          CS = name_of_coord_system

The master nodes are found using the standard master criterion. The stamping surface is defined using the given stamping direction and the cutting edge automatically generated by SIMULIA Tosca Structure. All nodes of the node group are linked to this surface.

An additional demolding direction can be included:

         DEMOLD_DIR = <x_1>,<x_2>,<x_3>

The demolding direction has to be orthogonal to the client direction. Therefore SIMULIA Tosca Structure projects the demold vector onto a plane normal to the client direction.

Important:

  • This link condition allows the definition of stamping restrictions to arbitrary meshes. No special meshing conditions have to be taken into consideration.
  • It is possible to define stamping restrictions for initial components which are not stampable in the beginning of the optimization procedure. However, this is not recommended because the conditions for stamping are met in the first design cycle. This may lead to large node displacements and a distorted finite element mesh.

Turnable surface (SURF_TURN)

Maintaining a turnable surface during optimization involves defining a rotation axis. The domain that assures a turnable surface is defined using a node group, i.e. all nodes of the specified surface node group are checked for rotation symmetry in the given rotation axis. The link condition is defined using the following parameters: 

        
          CLIENT = SURF_TURN
          CLIENT_DIR = <x_1>,<x_2>,<x_3>
          CS = name_of_coord_system

The direction defined by the CLIENT_DIR and the origin of the coordinate system specify the exact position and direction of the rotation axis.

The master nodes are found using the standard master criteria. The turning surface is defined using the given rotation axis and the cutting edge automatically generated by SIMULIA Tosca Structure. All nodes of the node group are linked to this surface.

Important:

  • This link condition allows the definition of turning restrictions to arbitrary meshes. No special meshing conditions have to be taken into consideration.
  • The referenced coordinate system must lie exactly on the rotation axis as the algorithm always orientates the surface towards the coordinate system. If non-symmetrical effects occur during optimization, the correct position of the coordinate system has to be checked.
  • It is possible to define turning restrictions for initial components that are not turnable in the beginning of the optimization procedure. However, this is not recommended because the conditions for turning are met in the first design cycle. This may lead to large node displacements and a distorted finite element mesh.

Drillable surface (SURF_DRILL)

The drill restriction is a combination of the turning and the demolding restriction. Maintaining a drillable surface during optimization involves defining the drill axis and the drill feed. The drilling domain is defined using a node group, i.e. all nodes of the specified surface node group are checked for drilling in the given drill direction. The link condition is defined using the following parameter: 

        
          CLIENT = SURF_DRILL
          CLIENT_DIR = <x_1>,<x_2>,<x_3>
          CS = name_of_coord_system
          ANGLE = <real> (0° < angle < 45°)

The direction defined by the CLIENT_DIR and the origin of the coordinate system specify the exact position and direction of the drill axis, the angle specifies a minimum surface angle.

The shape of the drilling surface can be specified with an additional undercut tolerance. The term 'drilling surface' in this case should be interpreted in a more general sense. 

         UNDERCUT_TOL = <real> (>0)


Important:

  • This link condition allows the definition of turning restrictions to arbitrary meshes. No special meshing conditions have to be taken into consideration.
  • The referenced coordinate system must lie exactly on the rotation axis as the algorithm always orientates the surface towards the coordinate system. If non-symmetrical effects occur during optimization, the correct position of the coordinate system has to be checked.
  • It is possible to define turning restrictions for initial components that are not turnable in the beginning of the optimization procedure. However, this is not recommended because the conditions for turning are met in the first design cycle. This may lead to large node displacements and a distorted finite element mesh.