hm_collisionentitycreate

Adds entities to consider for collision detection.

Syntax

hm_collisionentitycreate entity_type mark_id dimension thickness_type thickness edge_penetration midside_nodes split_quads used_topology grouping_identifier ?offset?

Type

HyperMesh Tcl Query Command

Description

Adds input entities to consider for collision detection. This must be called after hm_collisioninit, and before any calls to hm_collisionentitycreate.

Multiple calls to this API can be made to add additional input entities to the collision detection. Note that the input entities are different from the core collision entity. These commands do not operate on those entities, only on temporary memory.

When using the collirad collision detection engine, only one call is supported for each grouping_identifier. This means that either a single call to this API has to be made with grouping_identifier as 0, or one call with grouping_identifier 1 and 2 each.

Inputs

entity_type: The type of entity to add.; Valid values for the opcode engine are nodes, surfs, solids, elems and comps (only elems in comps are considered).; Valid values for the collirad engine are comps and groups.
mark_id: The ID of the mark containing the entities to add. Valid values are 1 and 2.
dimension: Defines the dimension of elements to consider. Valid only for elems and comps. Ignored by the collirad engine.; 0 - No restriction; 2 - 2D shells only; 3 - 3D solids only
thickness_type: Defines how the thickness is applied to the input entities, in combination with thickness.; 0 - Use the value specified by thickness.; 1 - Use component thickness.; 2 - Use element thickness. Valid only for elems and comps.; Add 10 to these values to also apply the thickness on the outside of solid elements or geometry (i.e. report solid skins being close to each other, but not intruding each other). Ignored by the collirad engine.; Add 20 to these values to also apply the thickness on the inside of solid elements or geometry, reporting a normal pointing outwards (i.e. report solids intruding each other). Ignored by the collirad engine.; Add 30 to these values to also apply the thickness on the inside and outside of solid elements or geometry, reporting a normal pointing outwards (i.e. combine the two options above). Ignored by the collirad engine.; Add 40 to these values to also apply the thickness to solid elements or geometry as if their skins were shell elements (i.e. report close faces with a normal pointing outwards, intruding faces with a normal pointing inwards). This affects the opcode engine, but the collirad engine always applies this logic.; Add 100 to these values to ignore penetrations of neighboring elements due to thicknesses being greater than element sizes. This corresponds to using Iremgap 2 in Radioss contact interfaces. This is ignored by the opcode engine.; Add 200 to these values to restrict the thickness of the elements to 40% of their size. This also avoids undesired penetrations of neighboring elements due to thicknesses being greater than element sizes. This corresponds to the behavior of some LS-DYNA contacts. This is ignored by the opcode engine.; Add 300 to these values to use thickness as a thickness multiplier when using component or element thickness. This is ignored by the collirad engine.; Add 400 to these values to use thickness as an add-on thickness when using component or element thickness. This is ignored by the collirad engine.; All values are ignored for groups, for which thicknesses are applied as in the solver.
thickness: The assigned uniform thickness when thickness_flag is 0. If thickness_flag has 300 or 400 added while using component or element thickness, thi sis used as a thickness multiplier or add-on.; Used as a multiplier for real thickness in the collirad engine.
edge_penetration: Not valid for groups for which the solver logic is applied.; 0 - Do not consider edge penetrations.; 1 - Consider edge penetrations.
midside_nodes: Valid only for elems and comps.; 0 - Do not consider midside nodes.; 1 - Consider midside nodes.
split_quads: Valid only for elems and comps.; 0 - Do not split quads at the center for calculation purposes. This is the default for the opcode engine, and is not available for the collirad engine.; 1 - Split quads at the center for calculation purposes. This is the default in the collirad engine.
used_topology: This is ignored for the collirad engine.; 0 - Consider specified entities.; 1 - Consider only nodes of specified entities.; 2 - Use all edges of elements or faces.; 3 - Use only free edges of shell elements.
grouping_identifier: Entities with the same grouping identifier are not checked against each other. This is useful for performing checks "by pair". If set to 0, entities are checked against all others.
offset: Used to specify which element types to offset using solver properties.; 0 - None.; 1 - Only bar/beam elements.; 10 - Only shell elements.; 11 - Both bar/beam and shell elements.

Examples

To find intersecting surfaces from IDs 1-10:

*createmark surfs 1 1-10
hm_collisioninit
hm_collisionentitycreate surfs 1 0 1 0 0 0 0 0 0
hm_collisioncheck 0 0 1 0 0 0 0
hm_collisionend
hm_getmark surfs 1

To find penetrating surfaces from IDs 1-10, using the thickness assigned to the surface components:

*createmark surfs 1 1-10
hm_collisioninit
hm_collisionentitycreate surfs 1 0 1 0 0 0 0 0 0
hm_collisioncheck 0 0 0 1 0 0 0
hm_collisionend
hm_getmark surfs 1

To find penetrating surfaces from IDs 1-5 with a uniform thickness of 1.5, against those with IDs 6-10 and uniform thickness 2.0, considering edge penetration effects:

hm_collisioninit
*createmark surfs 1 1-5
hm_collisionentitycreate surfs 1 0 1 1.5 1 0 0 0 1
*createmark surfs 1 6-10
hm_collisionentitycreate surfs 1 0 1 2.0 1 0 0 0 2
hm_collisioncheck 0 0 0 1 0 0 0
hm_collisionend
hm_getmark surfs 1

To find penetrating elements from components with IDs 1-5 using thickness defined on elements, offset defined on shell elements:

hm_collisioninit 
*createmark comps 1 1-5
hm_collisionentitycreate comps 1 0 2 0 0 0 0 0 0 10 
hm_collisioncheck 0 1 0 0 0 0 0 0 0 0 0 0
hm_collisionend
hm_highlightmark elems 1 "h"

To find penetrating elements from all components using a thickness multiplier of 1.1 on thickness defined on elements:

hm_collisioninit 
*createmark comps 1 all
hm_collisionentitycreate comps 1 0 302 1.1 0 0 0 0 0 
hm_collisioncheck 0 1 0 0 0 0 0 0 0 0 0 1
hm_collisionend
hm_highlightmark elems 1 "h"

Errors

Incorrect usage results in a Tcl error. To detect errors, you can use the catch command:

if { [ catch {command_name...} ] } {
   # Handle error
}

Version History

11.0.130

2017.1 - Updated the option descriptions to indicate their support for the opcode vs. collirad engines. Added values 100 and 200 to thickness_type.

2019 - Added new optional argument offset. Added values 300 and 300 to thickness_type.