The Attachment node is used to define a point or a set of points on a flexible beam which can be used to connect it with other components through a joint in the Multibody Dynamics interface. All the selected points behave as if they were connected by a common rigid body.
The Attachment node is available with the Multibody Dynamics Module. The use of attachments is discussed in the Attachments section in the Multibody Dynamics Module User’s Guide.