RBE1

Bulk Data Entry Defines a rigid body connected to an arbitrary number of grid points.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
RBE1 EID GN1 CN1 GN2 CN2 GN3 CN3    
    GN4 CN4 GN5 CN5 GN6 CN6    
  "UM" GM1 CM1 GM2 CM2 GM3 CM3    
    GM4 CM4 GM5 CM5 etc.      

Example

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
RBE1 14 100 123456            
  UM 101 123 102 123        

Definitions

Field Contents SI Unit Example
EID Unique element identification number. Must be unique.

No default (Integer)

  
GNi Grid points at which independent degrees-of-freedom for the element are assigned.

No default (Integer or <PartName.number>). 6

  
CNi Independent degrees-of-freedom in the global coordinate system for the rigid element at grid point(s) GNi.  
UM Indicates the start of the dependent degrees-of-freedom.  
GMi Grid points at which dependent degrees-of-freedom for the element are assigned.

No default (Integer or <PartName.number>). 6

  
CMi Dependent degrees-of-freedom in the global coordinate system for the rigid elements at grid point(s) GMi.

No default (Integers 1 through 6 with no embedded blanks)

  

Comments

  1. The total number of components in CN1 to CN6 must equal six; furthermore, they must jointly be capable of representing and general rigid body motion of the element. The first continuation entry is not required if there are fewer than four GN points.
  2. The degree-of-freedom declared dependent on this entry may not be:
    • Included in a single point constraint (SPC or SPC1)
    • Declared a dependent degree-of-freedom on any other RBAR, RBE1, RBE2, RBE3, or RROD entry
    • Declared a dependent degree-of-freedom on an MPC set referenced by a subcase
  3. 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.
  4. Rigid elements, unlike MPCs, may not be selected for use in individual subcases; they apply to all subcases.
  5. Rigid elements are ignored in heat transfer analysis.
  6. Supported local entries in specific parts can be referenced by the use of "fully qualified references" on RBE1 entries in the model. A fully qualified reference (PartName.number) is similar to the format of a numeric reference. PartName is the name of the part that contains the referenced local entry (part names are defined on the BEGIN Bulk Data Entry in the model). number is the identification number of a referenced local entry in the part PartName. See Parts and Instances in the User Guide for detailed information on the use of fully qualified references.