{HEAD ~ A frame support structure} is automatically positioned to {TAIL ~ a frame} receiving position where the frame is placed thereon 
is automatically positioned to
{ HEAD ~ A frame support structure } is automatically positioned to { TAIL ~ a frame } receiving position where the frame is placed thereon
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH