MBS Joints Panel

Use the MBS joints panel to define kinematic joints between two local coordinate systems to connect two multibody collectors. The HyperWorks entity created is an mbjoint.

Location: Analysis page > Safety module

The panel contains an organize systems option. When activated (default) during joint creation, two coordinate system collectors will be automatically created and the joint local coordinate systems will be placed in their respective collectors. Since joint local coordinate systems are usually coincident in global space (but not required), the "organize systems" option provides easy access to each joint system.

Care should be taken when creating joints without coincident joint coordinate because the exported model might not reflect the model in HyperWorks.

Joint types are defined by assigning a card image in the card image= field (in some solver interfaces, it is the type= field). If no card image is assigned, all DOFs are active.

The available joint types are dependent on the template file loaded with the solver interface.

When an mbjoint entity is created, a coordinate system hierarchy is created by:
  1. Referencing the child multibody collector's coordinate system to the joint child coordinate system.
  2. Referencing the joint child coordinate system to the joint parent coordinate system.
  3. Referencing the joint parent coordinate system to the parent multibody collector's coordinate system.

When an mbjoint entity is deleted in the Delete panel, the joint's child coordinate system is referenced to the global coordinate system.

Create Subpanel

Use the Create subpanel to create new MBS joints.
Option Action
name = Specify a name for the new joint.
card image = / type = Select a card image.
Note: In some solver interfaces this button is replaced by type =.
parent: color Select a color for the parent entity of the joint.
parent: syst Select the joint parent's coordinate system.
parent: multibody / reference space
multibody
Connect the joint to two bodies.
reference space
Connect the joint to the reference space.
mbjoint: color Select a color for the joint.
child: color Select a color for the child entity of the joint.
child: syst Select the joint child's coordinate system.
child: multibody Select the multibody collector that defines the joint's child body.
organize systs Separate the joint coordinate systems into new coordinate system collectors.

Update Subpanel

Use the Update subpanel to change the characteristics of an existing MBS joint.
Option Action
name = Select an existing MBS joint.
card image = /

type =

 Select a card image.
Note: In some solver interfaces this button is replaced by type =.
parent: syst Select the joint parent's coordinate system.
parent: multibody / reference space
multibody
Connect the joint to two bodies.
reference space
Connect the joint to the reference space.
mbjoint: color Select a color for the joint.
child: syst Select the joint child's coordinate system.
child: multibody Select the multibody collector that defines the joint's child body.

Card Image Subpanel

Use the Card Image subpanel to change the card image (or type, in some solver interfaces) assigned to an existing MBS joint.
Option Action
name = Select an existing MBS joint.
card image = /

type =

 Select a card image.
Note: In some solver interfaces this button is replaced by type =.

Command Buttons

Button Action
create Create the new MBS joint.
create/edit Create the new joint and open its assigned card image in edit mode.
update Change the selected joints to use the current input settings.
edit Edit the current MBS joint's card image.
load Load the selected MBS Joint's card image.
load/edit Load the selected MBS Joint's card image and display it in edit mode.
reject Undo the most recent joint creation or update.
reset Reset the joint's input settings to their original values.
reset all Reset all MBS joints in the model their original values.
return Exit the panel.