The cranks confine the motion of each of {HEAD ~ the transmission rings} to a non rotary, {TAIL ~ planetary motion} 
to
The cranks confine the motion of each of { HEAD ~ the transmission rings } to a non rotary , { TAIL ~ planetary motion }
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL