RBE3 Panel

Use the RBE3 panel to create, review, and update RBE3 elements.

Location: 1D page

RBE3's are interpolation constraint elements, where the motion of a dependent node is defined as the weighted average of the motions of a group of independent nodes. The dependent degrees of freedom and weighting factors can be specified or automatically calculated based on the geometry. RBE3 elements are element config 56 and are displayed as lines between the dependent node and the independent node(s) with RBE3 displayed at the dependent node of the element.

RBE3's are typically used to distribute loads applied on the dependent node amongst the selected independent nodes.
Note: The dependent node cannot be directly constrained, as this would lead to a double-dependency for that node.

Create Subpanel

Option Action
dependent
calculate node
Create the dependent node at the weighted average (root-mean-square) location of the selected independent nodes.
nodes
Select the desired dependent nodes from your model.
independent nodes Select the desired independent nodes from your model.
dependent dofs: (checkboxes) Select the degrees of freedom to transfer from the dependent node to the independent nodes.
weight = Specify the decimal proportion (0-1) of the force and moment loads distributed from the independent nodes to the dependent node for the selected DOF's.
Note: The proportion of moment load distributed will also be affected by the geometry (distance) between the dependent and independent nodes.
elem types = Select an element type.

Update Subpanel

Use the Update subpanel to edit the connectivity, DOFs, and weight for each node of the element.
Input Action
elem Select the desired RBE3 element.
connectivity Determines which additional fields display in the third column of the panel.
  • Indicate which element you want to update by selecting it on your model, or click elem to display the extended entity selection window.
  • Change the dependent node by clicking node under dependent, then select the node that you want to be the dependent node.
  • Add additional nodes by clicking nodes under independent, then left-click to select the nodes to add to the elements.
  • Remove independent nodes by clicking nodes under independent, then right-click to select the nodes to remove from the element.
dofs Determines which additional fields display in the third column of the panel.
  • Indicate which element you want to update by selecting it on your model, or click elem to display the extended entity selection window. The current DOFs applied to each node of the RBE3 element are displayed.
  • If the change to the DOFs applies to all the nodes of the RBE3 element, select the desired DOFs and click set all.
  • If the change is to individual nodes, choose set individual or select to type.
    set individual
    Select the DOFs to apply, then select the desired nodes to which you want to apply the selected DOFs.
    select to type
    Select the DOF numbers displayed by the node that you want to change. The existing DOF values are replaced with a numeric text box; enter in the DOF numbers that you wish the node to use and then press Enter.
Note: When you update the DOFs, only legal DOF values are accepted.
weight factors Determines which additional fields display in the third column of the panel.
  • Indicate which element you want to update by selecting it on your model, or click elem to display the extended entity selection window. The weight of each node of the RBE3 element is displayed.
  • If the change to the weight applies to all the nodes of the RBE3 element, enter the desired weight in weight = and click set all.
  • If the change is to individual nodes, choose set individual or select to adjust.
    set individual
    Specify the weight in weight = and then select the desired nodes to which you want to apply the weight.
    select to adjust
    Click the weight displayed by the node that you want to change. Left-click to increment the weight, or right-click to decrement it. Alternatively, left-click-and-drag to rapidly change the value (drag upwards for higher values, and downwards for lower ones).
elem types Select a element type to change the RBE3 to.

This option determines which additional fields display in the third column of the panel. In this case, only the elem types= field displays. Valid element types depend on the current solver profile.

Command Buttons

Button Action
create Create the new RBE3 to your specifications.
update Change the selected RBE3 to use the currently defined characteristics. Once updated, you can no longer reset to the original values. You can only reset to the updated values.
reject Undo the most recent create action.
review Click review, then select a RBE3 element. The selected RBE3's characteristics display in the subpanel's entry fields.
reset Reset the entry fields to their starting values (the RBE3 element's currently assigned values, as opposed to any changes you might have made without clicking update.)