As a result of this arrangement, {TAIL ~ rotations} of {HEAD ~ the arm} 12 about the axis 9 lengthen or shorten each helical cord 
As a result of this arrangement , { TAIL ~ rotations } of { HEAD ~ the arm } 12 about the axis 9 lengthen or shorten each helical cord
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH