Local axes of frames with offset joints

The local axes of frames with offset joints are determined as follows:

• Original axes (without offset) – Calculate local axes according to the local-1 axis, as oriented from joint i to joint j. Depending upon user specification, basic or advanced local-axes parameters are used. The local axes resolved are then displayed in the GUI.

• Local 1 – Once joints are offset, the frame may now have a local-1 axis which differs from that of the original orientation. The dot product of both the original and new local-1 axis are positive.

• Local 2 – The local-2 axis of the offset frame is parallel to the original local 1-2 plane.

• Local 3 – The local-3 axis is calculated as the cross product of the new local-1 and local-2 axes.