The motor controller sends out {HEAD ~ a signal} to control an electric motor and {TAIL ~ turbine} to generate the desired inspiratory and expiratory pressures 
to control
The motor controller sends out { HEAD ~ a signal } to control an electric motor and { TAIL ~ turbine } to generate the desired inspiratory and expiratory pressures
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH