Device for keeping the spatial attitude of {HEAD ~ a member}, constrained to {TAIL ~ a swinging support}, with respect to a fixed element 
constrained to
Device for keeping the spatial attitude of { HEAD ~ a member } , constrained to { TAIL ~ a swinging support } , with respect to a fixed element
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH