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