GB1331947A - Electrical automatic pilots for ships - Google Patents

Abstract

1331947 Automatic steering control ANSCHUTZ & CO GmbH 7 Oct 1970 [14 Oct 1969] 47774/70 Heading G3R A radio navigation receiver 1 on a ship 7 produces an output signal corresponding to the phase-angle between transmissions received from two different radio stations which is compared in a controller 2 with a signal corresponding to a desired phase angle set by a knob 123 so that any error is applied to adjust the datum of heading controller 3 and thus maintain the ship on a chosen hyperbolic radio course. Heading controller 3 compares a signal from a gyro 8, responsive to the ships' heading, with a signal corresponding to a manually set heading corrected by the error signal from controller 2. Any error signal from controller 3 is applied to a controller 4 adjusting the ships rudder 6 to correct the course, follow-up signals from a transducer 5 being fed back to controller 3. Controller 2 includes a transistorized detector, responsive to fall in positioning signals which occurs deliberately and periodically while approximate but unambiguous signals are transmitted which ensures that capacitively stored values of the last accurate signals are utilized for control until accurate signals are restored. Controller 2 also includes an error indicator, recorder and alarm, a switch which is operated to suit the direction of travel and a resistance-capacity PID network the sensitivity of which is manually adjustable. On first switching on, the heading error signal is fed back from controller 3 to controller 2 through AND gates to discharge the integrations feedback capacity. Suitable phase comparison networks including resolvers or potentiometers are described and digital computation is referred to.