| 摘要 |
1493152 Automatic course control ANSCHUTZ & CO GmbH 11 April 1975 [18 April 1974] 15085/75 Heading G3R In an autopilot for a rudder steered craft e.g. a ship, the rudder is controlled at least at the beginning of a change of course operation by the sum of a course error signal and a negative signal of decreasing magnitude. As shown, for use in a ship, when the course is to be changed, switch 22, Fig. 2, is closed and capacitor 26 in auxiliary circuit 20 charges up from the course error UE and discharges at a rate determined by variable resistor 28, to form a signal Us. This signal is subtracted by operational amplifier 18 from the error signal UE, the resultant UA being used to control the position of the ship's rudder, using an averaging circuit with a dead zone and a PID controller. The system is such that the rudder is altered slowly and at a rate irrespective of the desired change in course, with minimal loss of the ship's forward speed. In alternatives, Figs. 4 and 5 (not shown), the signal Us may have different slopes, each produced by a selected one of a plurality of auxiliary circuits 20, or by selecting different values of capacitor 26 in a single auxiliary circuit. The actual ship's course may be measured by a gyro-compass. |
