Navigation devices
US4132113A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 16, 1977 |
| Grant date | Jan 2, 1979 |
| Priority date | — |
| Expiry date | Feb 16, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C17/26
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A navigational device consisting of a magnetic compass containing a pattern having a specified relation of black-to-white density with respect to angle, rotating with the compass card, a light source for illumination of the pattern, pairs of sensors mounted in the compass and responsive to the light intensity reflected from or transmitted through the pattern, the output from one pair of sensors being proportional to the sine of the angle made by the sensor pair zero reference line with respect to Magnetic North, and the output of the other pair of sensors being proportional to the cosine of said angle, both outputs being suitable for operation of a remote indicating compass, and various modifications thereof for making the outputs of the sensor pairs proportional to the sine and cosine of the angle between a manually settable desired heading or angle and the angle of the said sensor pair zero reference line with respect to Magnetic North. Several additional features such as off-course alarm, drift vector insertion, and compensating means for craft pitch and roll are described and claimed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.