High precision stellar pointing device for spacecraft

Claim 2

A navigation apparatus incorporated in a stellar vehicle which comprises a support carried by said vehicle, a first stellar detector fixedly mounted on said support and having an optical axis directed toward a first star, a second detector also fixedly mounted on said support and having an optical axis which is directed toward a second star, said first and second detectors being offset from each other by a fixed known angle, means to control and propel said vehicle in accordance with a desired trajectory making predetermined angles with respect to the optical axes of said fixedly mounted detectors, a pair of generators connected respectively to said first and second detectors, each said generator serving to supply data corresponding to the error between the actual trajectory being followed by said vehicle and the direction of the corresponding star, processor means connected to the outputs of said generators for computing said data, and means connecting the output from said processor means to said controlling and propelling means for said vehicle.

Claim 3

A navigation apparatus as set forth in claim 1 comprising further a shock absorber inserted between said support and said vehicle.

Claim 4

A navigation apparatus as set forth in claim 1 comprising further adjustable means for fixedly mounting said stellar detectors and self-collimating means carried by each of said stellar detectors, whereby the optical axes of said first and second stellar detectors may be directed respectively toward said first and second stars before said detector is fixedly mounted on said support.

Claim 5

A navigation apparatus as set forth in claim 1 wherein said data processor means includes a first computer receiving data from said first and second stellar detectors and formulating a presence signal of the first and second stars within range of said first and second stellar detectors.

Claim 6

A navigation apparatus as set forth in claim 4 wherein said data processor means further includes a second computer receiving data from said first and second stellar detectors and formulating error signals of said first and second stars with respect to the optical axes of said first and second stellar detectors, said error signals being then processed with signals from said fixed known angle with respect to a specific guiding axis of the stellar vehicle for formulating pointing error signals with respect to said guiding axis.

Claim 7

A navigation apparatus as set forth in claim 1 wherein each of said first and second stellar detectors comprises a telescope with two catadioptric lenses, a pyramidal mirror having an axis parallel to the optical axis of the stellar detector and provided for separating a beam of light from each of said first and second stars in four pencil-like of light and four photo-multipliers receiving said four beams of light and constituting said generators receiving data corresponding to a direction of said first and second stars with respect to the optical axes of said first and second stellar detectors.

Claim 8

A navigation apparatus as set forth in claim 6, wherein the two catadioptric lenses are mounted in a cylindrical structure by means of conical rings ensuring the centering thereof and a metallic strut with a low dilatation coefficient ensuring the mutual spacing of said lenses, the assembly being maintained by means of a flexible ring whereby resistance to shocks and accelerations is obtained.

Claim 9

A navigation apparatus as set forth in claim 6, wherein the pyramidal mirror is mounted on a support comprising means for adjusting said mirror in a position corresponding to a linear response of the photo multipliers.

Claim 10

A navigation apparatus as set forth in claim 6, wherein the photomultipliers of a stellar detector are embedded in blocks.

Claim 11

A pointing unit for a stellar vehicle comprising a cylindrical housing mounted in said stellar vehicle, a support in said housing, shock absorber means inserted between said support and said housing, said housing having two windows and ejectable hatches in front of said two windows, a first optical stellar detector fixedly mounted on said support in front of one of said two windows and having its optical axis directable toward a first star, a second optical stellar detector also fixedly mounted on said support in front of the other one of said two windows and having its optical axis directable toward a second star, said first and second detectors being offset from each other by a fixed known angle, means to control and propel said vehicle according to a desired trajectory making predetermined angles with respect to said optical axes of said fixedly mounted detectors, said first and second detectors each having a generator supplying data subsequent to ejection of said hatches corresponding to errors between the trajectory followed by said vehicle and the direction of said star, data processor means connected to the outputs of said generators for computing said data, and means connecting the output from said data processor means to said controlling and propelling means for guiding said vehicle along the desired trajectory.

Claim 12

A pointing unit for a stellar vehicle comprising a cylindrical housing mounted in said stellar vehicle, a support in said housing, shock absorber means inserted between said support and said housing, said housing having two windows and ejectable hatches in front of said two windows, a first optical stellar detector fixedly mounted on said support in front of one of said two windows and having its optical axis directable toward a first star, a second optical stellar detector also fixedly mounted on said support in front of the other one of said two windows and having its optical axis directable toward a second star, said first and second detectors being offset from each other by a fixed known angle, means to control and propel said vehicle according to a desired trajectory making predetermined angles with respect to said optical axes of said fixedly mounted detectors, said first and second detectors each having a generator supplying data subsequent to ejection of said hatches corresponding to errors between the trajectory followed by said vehicle and the direction of said star, data processor means connected to the outputs of said generators for computing said data, and means connecting the output from said data processor means to said controlling and propelling means for guiding said vehicle along the desired trajectory.

Claim 13

A pointing unit as set forth in claim 10 wherein the optical axes of said first and second stellar detectors are respectively orthogonal and substantially perpendicular to the trajectory desired to be followed by said space craft.

Claim 14

A navigation apparatus as set forth in claim 6 wherein said pyramidal mirror is mounted at one end of an elongated support member and which includes means for adjusting said mirror longitudinally of said support member to a position corresponding to a linear response of said photo-multipliers, and wherein each said photo-multiplier is located within a cylindric block, said cylindric blocks being supported in a cluster about said elongated support member upon which said pyramidal mirror is mounted.