In an embodiment of the present invention, {HEAD ~ the control system} comprises a load measuring device, a summing junction, {TAIL ~ a logic control unit} and a process controller that encompasses a motor controller and a brake controller 
comprises
In an embodiment of the present invention , { HEAD ~ the control system } comprises a load measuring device , a summing junction , { TAIL ~ a logic control unit } and a process controller that encompasses a motor controller and a brake controller
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH