In FIG 1 is shown a wave gear drive comprising an inner gear having {HEAD ~ a given number} of external teeth and an outer gear having a slightly larger number of {TAIL ~ internal teeth} 
In FIG 1 is shown a wave gear drive comprising an inner gear having { HEAD ~ a given number } of external teeth and an outer gear having a slightly larger number of { TAIL ~ internal teeth }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL