Rigid Body Element, Form 1
Description: Defines a rigid body connected to an arbitrary number of grid points.
Format:
Example:
| Field | Definition | Type | Default |
|---|---|---|---|
| EID | Element identification number. | Integer > 0 | Required |
| GNi | Identification number of grid point to which independent degrees of freedom for the element are assigned. | Integer > 0 | Required |
| CNi | Independent degrees of freedom in the global coordinate system for the rigid element at grid points GNi. See Remark 1. (Up to six unique digits may be placed in the field with no embedded blanks.) | 1 ≤ Integers ≤ 6 | Required |
| GMj | Grid point identification numbers at which dependent degrees of freedom are assigned. | Integer > 0 | |
| CMj | Dependent degrees of freedom in the global coordinate system at grid points GMj. (Up to six unique digits may be placed in the field with no embedded blanks.) | 1 ≤ Integers ≤ 6 |
Remarks:
- A dependent degree of freedom assigned by one element cannot be assigned dependent by another rigid element or MPC entry and cannot be additionally constrained (e.g., single-point constraint).
- By default, a dependent degree of freedom assigned by one element cannot be assigned dependent by another rigid element or MPC entry and cannot be additionally constrained (e.g., single-point constraint). If this behavior is desired use PARAM, AUTOFIXRIGIDSPC which when set to ON will allow the constraint of dependent degrees of freedom. (See Section 5, Parameters, for more information on AUTOFIXRIGIDSPC.)
- A degree of freedom cannot be both independent and dependent for the same element. However, both independent and dependent components can exist at the same grid point.
- Rigid elements, unlike MPCs, are not selected through the Case Control Section.
- Forces of multipoint constraint may be recovered with the MPCFORCES Case Control command.