receiving {HEAD ~ an indication} from {TAIL ~ the second wireless communications device} that the second wireless communications device has reached a waypoint and sending the path data for a successive segment to the second wireless communications device in response to receiving the indication 
from
receiving { HEAD ~ an indication } from { TAIL ~ the second wireless communications device } that the second wireless communications device has reached a waypoint and sending the path data for a successive segment to the second wireless communications device in response to receiving the indication
OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH