Optical instrument tracking system

Claim 2

An automatic elevation surveying system wherein a laser beam is aligned with a movable target comprising: a support pedestal, a pivotal housing mounted on said support pedestal and including laser emitting a coherent beam mounted thereon, said housing operable to maintain said coherent beam at a predetermined attitude during rotation thereof, infrared wave detector means mounted in said housing, motor means responsive to the output of said infrared detector means for pivoting said housing toward the source of said infrared waves, and a beacon operable to emit infrared waves such that said laser beam is aligned with said movable target and such that impingement of said coherent beam on said movable target enables determination of a predetermined elevation at said movable target in response to the location of the impingement of said coherent beam on said target.

Claim 3

The surveying system of claim 1 wherein said beacon includes structure for attachment to a surveying stadia rod, whereby the coherent beam from said laser continuously impinges on said stadia rod to visually indicate said predetermined elevation at the stadia rod.

Claim 4

The surveying system of claim 1 wherein said infrared detector means comprises: at least two infrared wave detectors, circuitry for determining the relative signal amplitudes detected by said detectors, means for generating an error signal in response to said relative signal amplitudes, said motor means being operable in response to said error signal for rotating said housing in a horizontal plane.

Claim 5

The surveying system of claim 3 wherein said circuitry comprises: means for summing the signal amplitudes from said detectors, means for subtracting the signal amplitudes from said detectors, means for differentiating the summed signal amplitudes, and means responsive to the differentiated signal and the subtracted signal to generate an error signal indicative of the position of said beacon.

Claim 6

The surveying system of claim 1 and further comprising: means for sensing a loss of infrared signal received by said detector means, and means responsive to said loss of infrared signal for continuously rotating said housing until an infrared signal is again detected.

Claim 7

The surveying system of claim 1 and further comprising: means for maintaining said laser beam in a level orientation.

Claim 8

An automatic tracking elevation surveying system for maintaining a laser beam in alignment with a movable target comprising: a portable beacon for being connected to said movable target and for emitting predetermined electromagnetic waves, a support pedestal operable to be located remote from said movable target, a pivotal housing mounted on said support pedestal and including a laser for emitting a laser beam, said housing operable to maintain said laser beam in a single plane during rotation thereof, means on said housing for detecting said predetermined electromagnetic waves, motor means responsive to said detecting means for pivoting said housing to maintain said laser beam in alignment with said movable target wherein said laser beam impinges upon said target to provide elevational information at said target, means in said housing for sensing the loss of said predetermined electromagnetic waves, and means responsive to the loss of said predetermined electromagnetic waves for operating said motor means to continuously rotate said housing until said detecting means again detects said predetermined electromagnetic waves.

Claim 9

An automatic tracking elevation surveying system for maintaining a laser beam in alignment with a movable target comprising: a portable beacon for being connected to said movable target and for emitting predetermined electromagnetic waves, a support pedestal operable to be located remote from said movable target, a pivotal housing mounted on said support pedestal and including a laser for emitting a laser beam, said housing operable to maintain said laser beam in a single plane during rotation thereof, means on said housing for detecting said predetermined electromagnetic waves, motor means responsive to said detecting means for pivoting said housing to maintain said laser beam in alignment with said movable target wherein said laser beam impinges upon said target to provide elevational information at said target, means in said housing for sensing the loss of said predetermined electromagnetic waves, and means responsive to the loss of said predetermined electromagnetic waves for operating said motor means to continuously rotate said housing until said detecting means again detects said predetermined electromagnetic waves.

Claim 12

The method of claim 8 wherein said target comprises a stadia rod and said laser beam impinges on said stadia rod to indicate the desired elevation height, and whereiN said electromagnetic waves are in the infrared bank.

Claim 13

The method of claim 8 and further comprising: detecting a lack of reception of said waves at the housing, and continuously rotating the housing in a horizontal plane until said waves are again detected.