Articulated chassis 14 is supported for over the ground travel by a pair of front wheels 22 mounted to front frame section 16, and {HEAD ~ a pair} of {TAIL ~ rear wheels} 24 mounted to rear frame section 18 
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Articulated chassis 14 is supported for over the ground travel by a pair of front wheels 22 mounted to front frame section 16 , and { HEAD ~ a pair } of { TAIL ~ rear wheels } 24 mounted to rear frame section 18
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 HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH