A load force feeds into {HEAD ~ a PID controller} programmed with {TAIL ~ preset proportional, differential and integral parameters} 
programmed with
A load force feeds into { HEAD ~ a PID controller } programmed with { TAIL ~ preset proportional , differential and integral parameters }
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL