Automatic sextant
AssigneeKuau Technology, Ltd.
InventorJohn A. Decker, Jr.
Life of this patent
Estimating the term…
Abstract
A sextant for indicating the angular separation between two objects, including two members interconnected at a pivot point, means for adjusting the angle between the members to be indicative of the angular separation between the objects, the means for adjusting including coarse and fine adjustment means, and a pair of encoders for converting the respective positions of the coarse and fine adjustment means to signals which are together indicative of the angular separation. In other aspects, there is a single encoder having a track on the sextant arc and a sensor on the tangent arm; and an indicator tells the user when the sextant has been set to the prestored altitudes of reference celestial bodies.
Claims12
In a sextant comprising an assembly having a frame and an arm interconnected at a pivot point to permit rotation of said arm relative to said frame around said pivot point to change the angular position of said arm relative to said frame,
- said arm being movable relative to said frame for coarse adjustment of angle,
- a fine adjustment mechanism connected to said assembly and having a movable element motion of which causes a predetermined corresponding amount of fine adjustment of said angular position of said arm, the improvement comprising
- a coarse adjustment encoder connected to said assembly and arranged to detect and provide signals corresponding to the coarse unit value of a final angular position of said arm relative to said frame, and
- a fine adjustment encoder connected to said assembly and arranged to detect and provide signals corresponding to the fine unit value of said final angular position, and
- means connected to said encoders for deriving from said coarse and fine unit values an indication of an altitude angle of a celestial body.
- said coarse adjustment encoder having a resolution by itself insufficient to produce an indication of said altitude angle useful in conventional navigation.
The sextant of claim 3 wherein motion of said movable element of said fine adjustment mechanism is mechanically synchronized with motion of said arm relative to said frame by a gear track on said frame.
The sextant of claim 3 wherein said fine adjustment encoder has a resolution by itself insufficient to produce an indication of said altitude angle useful in conventional navigation.
A sextant system for making altitude observations comprising
- a sextant,
- a memory for storing reference altitude signals for a plurality of celestial bodies,
- means connected to said sextant for providing angle signals corresponding to the angular setting of said sextant,
- an indicator for alerting the user that said angular setting corresponds to said reference altitude of a selected celestial body, and
- circuitry for comparing said angle signals and said reference altitude signals and for triggering said indicator.
Dependencies are inferred from the claim text.