You can specify frame rotation using different methods. These include aligned axes, standard axis, and arbitrary axis. The different methods are available through the Rigid Transform block. The choice of method depends on the model. Select the method that is most convenient for the application.
Rotation is a relative quantity. The rotation of one frame is meaningful only with respect to another frame. As such, the Rigid Transform block requires two frames to specify a transformation: base and follower. The transformation operates on the base frame. For example, a translation along the +Z axis places the follower frame along the +Z axis from the base frame. Reversing frame ports is allowed, but the transformation is reversed: the base frame is now placed along the +Z axis from the follower frame.
Rotate two frames with respect to each other by aligning any two axes of one with any two axes of the other. The figure illustrates the aligned axes method.
Rotate frames with respect to each other about one of the three base frame axes: X, Y, or Z.
Rotate two frames with respect to each other about an arbitrary axis resolved in the base frame.