Adaptive autopilot for marine vessels
US4074648A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 18, 1976 |
| Grant date | Feb 21, 1978 |
| Priority date | — |
| Expiry date | Oct 18, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05D1/0206
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An autopilot automatically adjusts the sensitivity of a ship's steering system to accommodate changes in speed as well as sea and wind conditions. The autopilot utilizes heading error, speed and speed squared signals to produce a rudder order signal for controlling rudder position. The rudder order signal is developed in a heading keeping circuit unless a heading change greater than a predetermined threshold is commanded, in which event a programmer substitutes a heading change circuit for the heading keeping circuit. The sensitivity of the heading change circuit is automatically adjusted as an inverse function of vessel speed squared, and automatic rudder order limits are established in the same circuit as an inverse function of speed. The sensitivity of the heading keeping circuit is adjusted in accordance with a signal from an automatic gain control circuit which derives a performance index J from ship's speed, heading error and rudder order signals occurring during a given measurement interval. The performance index derived during a given measurement interval is compared with the index derived in the previous interval and a counter register is set according to the results of th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.