The dual angle and axis of a screw motion

The dual-number coordinate transformation matrix representing a screw motion through a general axis in space has been developed. A method for determining the axis and screw motion associated with a given dual-number coordinate transformation is also dealt with. Developing the dual-number matrix and determining the rotation angle from a given dual-number matrix is done in a manner analogous to that for handling simple rotations about axes intersecting the origin of the coordinate frame corresponding to the original position. By using dual-number methods, the axis of the motion may be any line in space and the translation along that axis can be considered when a screw motion has occurred.