{HEAD ~ The motion sensor} 1, wherein {TAIL ~ a position} of the adjusting bar is adjustable 
{ HEAD ~ The motion sensor } 1 , wherein { TAIL ~ a position } of the adjusting bar is adjustable
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH