Computer-stabilized magnetic compass

Claim 2

A computer-stabilized magnetic compass system for navigating a craft, comprising in combination: means mounted on said craft for sensing the horizontal component of the earth''s magnetic flux along the longitudinal axis thereof and for producing a first output signal proportional thereto; means mounted on said craft for sensing the horizontal component of the earth''s magnetic flux along the athwartship axis thereof and for producing a second output signal proportional thereto; means mounted on said craft for producing a third output signal proportional to the vertical component of the earth''s magnetic flux; means mounted on said craft for sensing the roll thereof relative to the vertical and for producing a fourth output signal proportional to the sine of the angle thereof; means mounted on said craft for sensing the roll thereof relative to the vertical and for producing a fifth output signal proportional to the cosine of the angle thereof; means mounted on said craft for sensing the pitch thereof relative to the vertical and for producing a sixth output signal proportional to the sine of the angle thereof; means mounted on said craft for sensing the pitch thereof relative to the vertical and for producing a seventh output signal proportional to the cosine of the angle thereof; means connected to the outputs of each of the aforesaid means for producing an eighth signal proportional to the compass heading of said craft relative to magnetic north that is compensated for the roll and pitch thereof in response to the aforesaid first through seventh output signals; and means connected to the output of said last mentioned means for reading out said eighth output signal.

Claim 3

The device of claim 1 wherein said means mounted on said craft for sensing the horizontal component of the earth''s magnetic flux along the horizontal axis thereof and for producing a first output signal proportional thereto comprises a magnetometer.

Claim 4

The device of claim 1 wherein said means mounted on said craft for sensing the horizontal component of the earth''s magnetic flux along the athwartship axis thereof and for producing a second output signal proportional thereto comprises a magnetometer.

Claim 5

The device of claim 1 wherein said means mounted on said craft for producing a third output signal proportional to the vertical component of the earth''s magnetic flux comprises a manually adjustable voltage generator.

Claim 6

The device of claim 1 wherein said means mounted on said craft for producing a third output signal proportional to the vertical component of the earth''s magnetic flux comprises: a magnetometer: and means connected to said magnetometer for the maintenance thereof in such disposition as to cause it to continuously sense said vertical component of the earth''s magnetic flux.

Claim 7

The device of claim 1 wherein said means mounted on said craft for producing a third output signal proportional to the vertical component of the earth''s magnetic flux compriSes: a manually adjustable voltage generator; a magnetometer; and a selector switch having a pair of inputs and an output, with one of the inputs thereof connected to the output of said manually adjustable voltage generator, and with the other input there connected to the output of the aforesaid magnetometer.

Claim 8

The device of claim 1 wherein said fourth, fifth, sixth, and seventh output signal producing means are each accelerometers.

Claim 9

The device of claim 1 wherein said means connected to the outputs of each of the aforesaid means for producing an eighth output signal proportional to the compass heading of said craft relative to magnetic north that is compensated for the roll and pitch thereof in response to the aforesaid first through seventh output signals comprises a computer.

Claim 10

The device of claim 1 wherein said means connected to the outputs of each of the aforesaid means for producing an eighth output signal proportional to the compass heading of said craft relative to magnetic north that is compensated for the roll and pitch thereof in response to the aforesaid first through seventh output signals comprises: a first adder having a pair of inputs and an output, with one of the inputs thereof effectively connected to the output of the aforesaid first output signal producing means; subtracter having a trio of inputs and an output, with one of the inputs thereof effectively connected to the output of the aforesaid second output signal producing means; a first multiplier having a pair of inputs and an output, with one of the inputs thereof effectively connected to the output of the aforesaid third output signal producing means, with the other input thereof effectively connected to the output of the aforesaid sixth output signal producing means, and with the output thereof connected to the other input of said first adder; a second multiplier having a trio of inputs and an output, with one of the inputs thereof effectively connected to the output of the aforesaid third output signal producing means, with another of inputs thereof connected to the output of the aforesaid fourth output signal producing means, with the remaining input thereof connected to the output of the aforesaid seventh output signal producing means, and with the output thereof connected to another input of said subtracter; a third multiplier having a trio of inputs and an output, with one of the inputs thereof connected to the output of the aforesaid fourth output signal producing means, with another of the inputs thereof connected to the output of the aforesaid sixth output signal producing means, and with the output thereof connected to the remaining input of said subtracter; a first divider having a pair of inputs and an output, with one of the inputs thereof connected to the output of said first adder, with the other input thereof connected to the output of the aforesaid seventh output signal producing means, and with the output thereof connected to the remaining input of said third multiplier; a second divider having a pair of inputs and an output, with one of the inputs thereof connected to the output of said subtracter, and with the other input thereof connected to the output of the aforesaid fifth output signal producing means; a first squaring circuit connected to the output of said first divider; a second squaring circuit connected to the output of said second divider; a second adder having a pair of inputs and an output, with the inputs thereof respectively connected to the outputs of said first and second squaring circuits; a square root circuit connected to the output of said second adder; a third divider having a pair of inputs and an output, with one of the inputs thereof connected to the output of said square root circuit, and with the other input thereof connected to the output of the aforesaid first divider; a variable direct current voltage generator; a relay having a pair of inputs and an ouTput, with one of the inputs thereof connected to the output of said variable direct current voltage generator, and with the other input thereof connected to the output of the aforesaid second divider; a diode connected to the output of said relay; and a servomechanism resolver having a pair of inputs and a pair of outputs, with one of the inputs thereof connected to the output of said diode, and with the other input thereof connected to the connected to the output of the aforesaid third divider.

Claim 11

The device of claim 1 wherein said means connected to the output of said last-mentioned means for reading out said eighth output signal is a compass readout comprising: a reversible motor; and a rotatable compass card connected to the shaft of said reversible motor.

Claim 12

A computer stabilized magnetic compass system for navigating a craft, comprising in combination: means mounted on said craft for sensing the horizontal component of the earth''s magnetic flux along the longitudinal axis thereof and for producing a first output signal proportional thereto; means mounted on said craft for sensing the horizontal component of the earth''s magnetic flux along the athwartship axis thereof and for producing a second output signal proportional thereto; mounted on said craft for producing a third output signal proportional to the vertical component of the earth''s magnetic flux; means mounted on said craft for sensing the roll thereof relative to the vertical and for producing a fourth output signal proportional to the sine of the angle thereof; means mounted on said craft for sensing the roll thereof relative to the vertical and for producing a fifth output signal proportional to the cosine of the angle thereof; means mounted on said craft for sensing the pitch thereof relative to the vertical and for producing a sixth output signal proportional to the sine of the angle thereof; means mounted on said craft for sensing the pitch thereof relative to the vertical and for producing a seventh output signal proportional to the cosine of the angle thereof; a first adder having a pair of inputs and an output, with one of the inputs thereof effectively connected to the output of the aforesaid first output signal producing means; a subtracter having a trio of inputs and an output, with one of the inputs thereof effectively connected to the output of the aforesaid second output signal producing means; a first multiplier having a pair of inputs and an output, with one of the inputs thereof effectively connected to the output of the aforesaid third output signal producing means, with other input thereof effectively connected to the output of the aforesaid sixth output signal producing means, and with the output thereof connected to the other input of said first adder; a second multiplier having a trio of inputs and an output, with one of the inputs effectively connected to the output of the aforesaid third output signal producing means, with another of inputs thereof connected to the output of the aforesaid fourth output signal producing means, with the remaining input thereof connected to the output of the aforesaid seventh output signal producing means, and with the output thereof connected to another input of said subtracter; a third multiplier having a trio of inputs and an output, with one of the inputs thereof connected to the output of the aforesaid fourth output signal producing means, with another of the inputs thereof connected to the output of the aforesaid sixth output signal producing means, and with the output thereof connected to the remaining input of said subtracter; a first divider having a pair of inputs and an output, with one of the inputs thereof connected to the output of said first adder, with the other input thereof connected to the output of the aforesaid seventh output signal producing means, and with the output thereof connected to the remaining input of said third multipliEr; a second divider having a pair of inputs and an output, with one of the inputs thereof connected to the output of said subtracter, and with the other input thereof connected to the output of the aforesaid fifth output signal producing means; a first squaring circuit connected to the output of said first divider; a second squaring circuit connected to the output of said second divider; a second adder having a pair of inputs and an output, with the inputs thereof respectively connected to the outputs of said first and second squaring circuits; a square root circuit connected to the output of said second adder; a third divider having a pair of inputs and an output, with one of the inputs thereof connected to the output of said square root circuit, and with the other input thereof connected to the output of the aforesaid first divider; a variable direct current voltage generator; a relay having a pair of inputs and an output, with one of the inputs thereof connected to the output of said variable direct current voltage generator, and with the other input thereof connected to the output of the aforesaid second divider; a diode connected to the output of said relay; and a servomechanism resolver having a pair of inputs and a pair of outputs, with one of the inputs thereof connected to the output of said diode, and with the other input thereof connected to the output of the aforesaid third divider.

Claim 13

A computer stabilized magnetic compass system for navigating a craft, comprising in combination: means mounted on said craft for sensing the horizontal component of the earth''s magnetic flux along the longitudinal axis thereof and for producing a first output signal proportional thereto; means mounted on said craft for sensing the horizontal component of the earth''s magnetic flux along the athwartship axis thereof and for producing a second output signal proportional thereto; mounted on said craft for producing a third output signal proportional to the vertical component of the earth''s magnetic flux; means mounted on said craft for sensing the roll thereof relative to the vertical and for producing a fourth output signal proportional to the sine of the angle thereof; means mounted on said craft for sensing the roll thereof relative to the vertical and for producing a fifth output signal proportional to the cosine of the angle thereof; means mounted on said craft for sensing the pitch thereof relative to the vertical and for producing a sixth output signal proportional to the sine of the angle thereof; means mounted on said craft for sensing the pitch thereof relative to the vertical and for producing a seventh output signal proportional to the cosine of the angle thereof; a first adder having a pair of inputs and an output, with one of the inputs thereof effectively connected to the output of the aforesaid first output signal producing means; a subtracter having a trio of inputs and an output, with one of the inputs thereof effectively connected to the output of the aforesaid second output signal producing means; a first multiplier having a pair of inputs and an output, with one of the inputs thereof effectively connected to the output of the aforesaid third output signal producing means, with other input thereof effectively connected to the output of the aforesaid sixth output signal producing means, and with the output thereof connected to the other input of said first adder; a second multiplier having a trio of inputs and an output, with one of the inputs effectively connected to the output of the aforesaid third output signal producing means, with another of inputs thereof connected to the output of the aforesaid fourth output signal producing means, with the remaining input thereof connected to the output of the aforesaid seventh output signal producing means, and with the output thereof connected to another input of said subtracter; a third multiplier having a trio of inputs and an output, with one of the inputs thereof connected to the output of the aforesaid fourth output signal producing means, with another of the inputs thereof connected to the output of the aforesaid sixth output signal producing means, and with the output thereof connected to the remaining input of said subtracter; a first divider having a pair of inputs and an output, with one of the inputs thereof connected to the output of said first adder, with the other input thereof connected to the output of the aforesaid seventh output signal producing means, and with the output thereof connected to the remaining input of said third multipliEr; a second divider having a pair of inputs and an output, with one of the inputs thereof connected to the output of said subtracter, and with the other input thereof connected to the output of the aforesaid fifth output signal producing means; a first squaring circuit connected to the output of said first divider; a second squaring circuit connected to the output of said second divider; a second adder having a pair of inputs and an output, with the inputs thereof respectively connected to the outputs of said first and second squaring circuits; a square root circuit connected to the output of said second adder; a third divider having a pair of inputs and an output, with one of the inputs thereof connected to the output of said square root circuit, and with the other input thereof connected to the output of the aforesaid first divider; a variable direct current voltage generator; a relay having a pair of inputs and an output, with one of the inputs thereof connected to the output of said variable direct current voltage generator, and with the other input thereof connected to the output of the aforesaid second divider; a diode connected to the output of said relay; and a servomechanism resolver having a pair of inputs and a pair of outputs, with one of the inputs thereof connected to the output of said diode, and with the other input thereof connected to the output of the aforesaid third divider.

Claim 14

The invention of claim 11 further characterized by utilization apparatus means connected to the output of said servomechanism resolver for navigating the aforesaid craft.