/MERGE/RBODY
Block Format Keyword Defines the merging of entities to a main rigid body.
Format
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
---|---|---|---|---|---|---|---|---|---|
/MERGE/RBODY/merge_ID | |||||||||
merge_title | |||||||||
main_ID | m_type | second_ID | s_type | Iflag |
Definition
Field | Contents | SI Unit Example |
---|---|---|
merge_ID | Rigid body merge
identifier. (Integer, maximum 10 digits) |
|
merge_title | Rigid body merge
title. (Character, maximum 100 characters) |
|
main_ID | Main rigid body
identifier. (Integer, maximum 10 digits) |
|
m_type | Main rigid body type flag.
(Integer) |
|
second_ID | Secondary rigid body
identifier. (Integer, maximum 10 digits) |
|
s_type | Secondary entity type flag.
(Integer) |
|
Iflag | Merge option flag.
2
(Integer) |
Comments
- Line 1 can be repeated to define multiple rigid body merges within one block.
- All secondary rigid body nodes (secondary and main) become secondary nodes of the main rigid body.
- Before merging, the inertia, mass, and center of gravity of each secondary and main rigid body is calculated based on their /RBODY properties. Next, the secondary entities are merged to the main rigid body and new rigid body properties are calculated based on the Iflag option.
- For s_type =2 (node_ID) and =3, (/GRNOD), the secondary entities can only be defined in one /MERGE/RBODY and not in any /RBODY.
- The main rigid body defined in a /MERGE/RBODY can be defined as a secondary rigid body in another /MERGE/RBODY. However, complex hierarchies should be avoided, as they can become difficult to debug.
- All kinematic conditions, initial velocity, and gravity loading applied to the secondary rigid body main node are ignored.
- The secondary rigid body sens_ID, Skew_ID, Ispher, Ikrem, surf_ID, and Ioptoff options are ignored. The merged rigid body will use the flags defined in the main rigid body.
- The merged rigid body can be activated or deactivated with /SENSOR or using the /RBODY/ON or /RBODY/OFF Engine option.
- If a secondary rigid body is defined in a time history output (/TH/RBODY), the main rigid body will automatically be included in the time history output, instead of the secondary rigid body.
- /MERGE/RBODY cannot be used with a rigid body that is the main surface of an /INTER/TYPE21 contact.