This system models a Sperry A-2 automatic pilot system. For each channel a pneumatic mechanism is activated when there is a position error. It drives a pneumatic valve that controls the direction and rate of change for the hydraulic actuator (Possibly just in an on/off fashion). The channel's speed valve controls the maximum rate of change for the actuator. See excerpt from [Your Wings, 1936] at http://pantonov.com/thoughts/assen_jordanoff.img/the_sperry_autopilot.htm Additional ideas: - The available vacuum suction probably affects the resonsiveness of the pneumatic valve. - The available oil pressure probably affects the maximum rate of change for the actuator. - The JSBSim actuator component in each channel is probably redundant. sperry-autopilot/enabled-cmd-norm sperry-autopilot/heading-reference-deg sperry-autopilot/pitch-reference-deg sperry-autopilot/roll-reference-deg sperry-autopilot/heading-speed-valve-cmd-norm sperry-autopilot/pitch-speed-valve-cmd-norm sperry-autopilot/roll-speed-valve-cmd-norm sperry-autopilot/aileron-cmd-norm sperry-autopilot/elevator-cmd-norm sperry-autopilot/rudder-cmd-norm sperry-autopilot/heading/actuator-max-rate sperry-autopilot/pitch/actuator-max-rate sperry-autopilot/roll/actuator-max-rate sperry-autopilot/heading/sensitivity sperry-autopilot/pitch/sensitivity sperry-autopilot/roll/sensitivity 57.29578 attitude/heading-true-rad 57.29578 attitude/pitch-rad 57.29578 attitude/roll-rad sperry-autopilot/heading-reference-deg sperry-autopilot/sensors/heading-deg sperry-autopilot/heading/error-raw-deg LT -180.0 sperry-autopilot/heading/error-raw-deg GT 180.0 sperry-autopilot/heading/error-raw-deg sperry-autopilot/heading/error-correction-deg -1.0 sperry-autopilot/heading/sensitivity sperry-autopilot/heading/error-deg -1.0 1.0 sperry-autopilot/heading-speed-valve-cmd-norm sperry-autopilot/heading/actuator-max-rate sperry-autopilot/heading/rate-cmd-norm LT 0.0 sperry-autopilot/heading/pid LT -1.0 sperry-autopilot/heading/rate-cmd-norm GT 0.0 sperry-autopilot/heading/pid GT 1.0 sperry-autopilot/enabled-cmd-norm EQ 0.0 sperry-autopilot/heading/rate-cmd-norm 0.0 sperry-autopilot/heading/max-rate sperry-autopilot/heading/windup-trigger sperry-autopilot/heading/pid -1.0 1.0 sperry-autopilot/enabled-cmd-norm sperry-autopilot/heading/actuator-pos

sperry-autopilot/rudder-cmd-norm

sperry-autopilot/pitch-reference-deg sperry-autopilot/sensors/pitch-deg -1.0 sperry-autopilot/pitch/sensitivity sperry-autopilot/pitch/error-deg -1.0 1.0 sperry-autopilot/pitch-speed-valve-cmd-norm sperry-autopilot/pitch/actuator-max-rate sperry-autopilot/pitch/rate-cmd-norm LT 0.0 sperry-autopilot/pitch/pid LT -1.0 sperry-autopilot/pitch/rate-cmd-norm GT 0.0 sperry-autopilot/pitch/pid GT 1.0 sperry-autopilot/enabled-cmd-norm EQ 0.0 sperry-autopilot/pitch/rate-cmd-norm 0.0 sperry-autopilot/pitch/max-rate sperry-autopilot/pitch/windup-trigger sperry-autopilot/pitch/pid -1.0 1.0 sperry-autopilot/enabled-cmd-norm sperry-autopilot/pitch/actuator-pos

sperry-autopilot/elevator-cmd-norm

sperry-autopilot/roll-reference-deg sperry-autopilot/sensors/roll-deg sperry-autopilot/roll/sensitivity sperry-autopilot/roll/error-deg -1.0 1.0 sperry-autopilot/roll-speed-valve-cmd-norm sperry-autopilot/roll/actuator-max-rate sperry-autopilot/roll/rate-cmd-norm LT 0.0 sperry-autopilot/roll/pid LT -1.0 sperry-autopilot/roll/rate-cmd-norm GT 0.0 sperry-autopilot/roll/pid GT 1.0 sperry-autopilot/enabled-cmd-norm EQ 0.0 sperry-autopilot/roll/rate-cmd-norm 0.0 sperry-autopilot/roll/max-rate sperry-autopilot/roll/windup-trigger sperry-autopilot/roll/pid -1.0 1.0 sperry-autopilot/enabled-cmd-norm sperry-autopilot/roll/actuator-pos

sperry-autopilot/aileron-cmd-norm