Apparatus for providing an analog or the like of the angular velocity of a rotating body

Claim 2

Apparatus for producing a high resolution alternating output signal of a high frequency directly proportional to angular velocity, said apparatus comprising: a base; a body rotatable on said base; an articulated member fixed relative to said body; pickup means fixed relative to said base in a position for cooperation with said member to produce at least a first alternating signal of a frequency omega directly proportional to the angular velocity of said body; a source of a second alternating signal of a constant frequency Omega independent of omega ; and output means connected from said pickup means and from said source for producing a third alternating signal directly proportional to the difference between said frequencies omega and Omega .

Claim 3

The invention as defined in claim 1, wherein said articulated member includes a ring of equally spaced ferromagnetic teeth fixed relative to said body in a position concentric with the rotational axis thereof, said pickup means including first and second magnetic pickups fixed relative to said base at different positions around said ring of teeth, said second pickup being angularly spaced from said first pickup in the direction of motion of said body an angle approximately equal to theta p where theta p (n - 1/4 ) theta t n is any positive integer, and theta t is the spacing between each pair of immediately adjAcent teeth, said output means including an adder, first and second multiplicative mixers connected from the output of said first and second pickups, respectively, to two respective inputs of said adder, a 90* phase shifter, the output of said source being connected to another input of said first mixer and to the input of said phase shifter, the output of said phase shifter being connected to another input of said second mixer.

Claim 4

Apparatus for producing a high resolution alternating output signal of a high frequency directly proportional to angular velocity, said apparatus comprising: a base, a body rotatable on said base; an articulated member fixed relative to said body; pickup means fixed relative to said base in a position for cooperation with said member to produce at least a first alternating signal of a frequency omega directly proportional to the angular velocity of said body; a source of a second alternating signal of a constant frequency Omega independent of omega ; and output means connected from said pickup means and from said source for producing a third alternating signal directly proportional to the difference between said frequencies omega and Omega , said articulated member body in a position concentric with the rotational axis thereof, said pickup means including first and second magnetic pickups fixed relative to said base at different positions around said ring of teeth, said second pickup being angularly spaced from said first pickup in the direction of motion of said body an angle approximately equal to theta p where theta p (n - 1/4 ) theta t n is any positive integer, and theta t is the spacing between each pair of immediately adjacent teeth, said output means including an adder, first and second multiplicative mixers connected from the output of said first and second pickups, respectively, to two respective inputs of said adder, a 90* phase shifter, the output of said source being connected to another input of said first mixer and to the input of said phase shifter, the output of said phase shifter being connected to another input of said second mixer, a low pass filter being connected from the output of said adder, and a frequency discriminator being connected from the output of said low pass filter.

Claim 5

Apparatus for producing a high resolution alternating output signal of a high frequency directly proportional to angular velocity, said apparatus comprising: a base, a body rotatable on said base; an articulated member fixed relative to said body; pickup means fixed relative to said base in a position for cooperation with said member to produce at least a first alternating signal of a frequency omega directly proportional to the angular velocity of said body; a source of a second alternating signal of a constant frequency Omega independent of omega ; and output means connected from said pickup means and from said source for producing a third alternating signal directly proportional to the difference between said frequencies omega and Omega , said articulated member body in a position concentric with the rotational axis thereof, said pickup means including first and second magnetic pickups fixed relative to said base at different positions around said ring of teeth, said second pickup being angularly spaced from said first pickup in the direction of motion of said body an angle approximately equal to theta p where theta p (n - 1/4 ) theta t n is any positive integer, and theta t is the spacing between each pair of immediately adjacent teeth, said output means including an adder, first and second multiplicative mixers connected from the output of said first and second pickups, respectively, to two respective inputs of said adder, a 90* phase shifter, the output of said source being connected to another input of said first mixer and to the input of said phase shifter, the output of said phase shifter being connected to another input of said second mixer, a low pass filter being connected from the output of said adder, and a frequency discriminator being connected from the output of said low pass filter.

Claim 6

The invention as defined in claim 1, wherein said pickup means includes a first pickup for producing said first signal and a second pickup for producing a first auziliary alternating signal of the same frequency omega , but leading said first signal in phase by 90*, said output means including first and second multiplicative mixers connected from the outputs of said first and second pickups, respectively, first auxiliary means connected from said source for impressing a second auxiliary alternating signal of said frequency Omega on said first mixer, second auxiliary means for impressing a third auxiliary alternating signal of said freuqency Omega on said second mixer, said third auxiliary signal leading said second auxiliary signal in phase by 90*, and an adder connected from both of the outputs of said mixers.

Claim 7

Apparatus for producing a high resolution alternating output signal of a high frequency directly proportional to angular velocity, said apparatus comprising: base; a body rotatable on said base; an articulated member fixed relative to said body; pickup means fixed relative to said base in a position for cooperation with said member to produce at least a first alternating signal of a frequency omega directly proportional to the angular velocity of said body; a source of a second alternating signal of a constant frequency Omega independent of omega ; and output means connected from said pickup means and from said source for producing a third alternating signal directly proportional to the difference between said frequencies omega and Omega , said pickup means including a first pickup for producing said first signal and a second pickup for produciNg a first auxiliary alternating signal of the same frequency omega , but leading said first signal in phase by 90*, said output means including first and second multiplicative mixers connected from the outputs of said first and second pickups, respectively, first auxiliary means connected from said source for impressing a second auxiliary alternating signal of said frequency Omega on said first mixer, second auxiliary means connected from said source for impressing a second auxiliary alternating signal of said frequency Omega on said first mixer, second auxiliary means for impressing a third auxiliary alternating signal of said frequency Omega on said second mixer, said third auxiliary signal leading said second auxiliary signal in phase by 90*, and an adder connected from both of the outputs of said mixers, a low pass filter and a frequency discriminator being connected in that order from the output of said adder.

Claim 8

Apparatus for producing a high resolution alternating output signal of a high frequency directly proportional to angular velocity, said apparatus comprising: base; a body rotatable on said base; an articulated member fixed relative to said body; pickup means fixed relative to said base in a position for cooperation with said member to produce at least a first alternating signal of a frequency omega directly proportional to the angular velocity of said body; a source of a second alternating signal of a constant frequency Omega independent of omega ; and output means connected from said pickup means and from said source for producing a third alternating signal directly proportional to the difference between said frequencies omega and Omega , said pickup means including a first pickup for producing said first signal and a second pickup for produciNg a first auxiliary alternating signal of the same frequency omega , but leading said first signal in phase by 90*, said output means including first and second multiplicative mixers connected from the outputs of said first and second pickups, respectively, first auxiliary means connected from said source for impressing a second auxiliary alternating signal of said frequency Omega on said first mixer, second auxiliary means connected from said source for impressing a second auxiliary alternating signal of said frequency Omega on said first mixer, second auxiliary means for impressing a third auxiliary alternating signal of said frequency Omega on said second mixer, said third auxiliary signal leading said second auxiliary signal in phase by 90*, and an adder connected from both of the outputs of said mixers, a low pass filter and a frequency discriminator being connected in that order from the output of said adder.

Claim 9

The invention as defined in claim 5, wherein said filter has a cutoff frequency between about Omega and the maximum of the difference frequency, ( Omega - omega ).

Claim 10

A single sideband modulator comprising: first means for producing a first output signal approximately proportional to U1 where U1 U sin omega t, U is a constant, omega is a radian frequency, and t is time; second means for producing a second output signal approximately proportional to U2 where U2 U cos omega t; third means for producing a third output signal approximately proportional to UH1a where UH1a UH sin ( Omega t + gamma ), UH is a constant, Omega is a radian frequency, and gamma is a constant; fourth means for producing a fourth output signal approximately proportional to UH2a where UH2a UH cos ( Omega t + gamma ); fifth means connected from said first and third means for producing a fifth signal approximately proportional to the first product U1UH1a; sixth means connected from said second and fourth means for producing a sixth signal approximately proportional to a second product U2UH2a; seventh means connected from said fifth and sixth means for producing a seventh signal approximately proportional to the sum of said first and second products, said sum being equal to UM4a + UM5a UUH cos (( Omega - omega ) t + gamma ) where UM4a U1UH1a, and UM5a U2UH2a; a low pass filter having an input lead and an output lead; and a frequency discriminator having an input lead and an output lead, said seventh means having an output lead, said filter input lead being connected from said seventh means output lead, said frequency discriminator input lead being connected from said filter output lead.

Claim 11

A single sideband modulator comprising: first means for producing a first output signal approximately proportional to U1 where U1 U sin omega t, U is a constant, omega is a radian frequency, and t is time; second means for producing a second output signal approximately proportional to U2 where U2 U cos omega t; third means for producing a third output signal approximately proportional to UH1a where UH1a UH sin ( Omega t + gamma ), UH is a constant, Omega is a radian frequency, and gamma is a constant; fourth means for producing a fourth output signal approximately proportional to UH2a where UH2a UH cos ( Omega t + gamma ); fifth means connected from said first and third means for producing a fifth signal approximately proportional to the first product U1UH1a; sixth means connected from said second and fourth means for producing a sixth signal approximately proportional to a second product U2UH2a; seventh means connected from said fifth and sixth means for producing a seventh signal approximately proportional to the sum of said first and second products, said sum being equal to UM4a + UM5a UUH cos (( Omega - omega ) t + gamma ) where UM4a U1UH1a, and UM5a U2UH2a; a low pass filter having an input lead and an output lead; and a frequency discriminator having an input lead and an output lead, said seventh means having an output lead, said filter input lead being connected from said seventh means output lead, said frequency discriminator input lead being connected from said filter output lead.

Claim 12

The invention as defined in claim 7, wherein the frequency Omega is substantially larger than the largest expected frequency omega .

Claim 13

The invention as defined in claim 8, wherein said low pass filter has a cutoff frequency between about the highest expected difference frequency, ( Omega - omega ), and the lowest expected sum frequency, ( Omega + omega ).

Claim 14

The invention as defined in claim 1, including a frequency discriminator responsive to said third alternating signal.

Claim 15

The invention as defined in claim 2, including a frequency discriminator responsive to the output of said adder.

Claim 16

The invention as defined in claim 4, including a frequency discriminator responsive to the output of said adder.

Claim 17

Apparatus for producing a high resolution alternating output signal of a high frequency directly proportional to angular velocity, said apparatus comprising a base; a body rotatable on said base; an articulatEd ferromagnetic member fixed relative to said body, said articulated member including a ring of equally spaced ferromagnetic teeth fixed to said body in a position concentric with the rotational axis thereof; a first magnetic pickup fixed relative to said base in a position for cooperation with said member to produce a first alternating signal of a first frequency directly proportional to the angular velocity of said body; a first source of a second alternating signal of a constant second frequency; a second source of a third alternating signal of said first frequency operably synchronously with said first pickup, said third signal being 90* out of phase with said first signal; and output means connected from said first pickup and said second and third sources for producing a fourth alternating signal directly proportional to the difference between said first and second frequencies, said output means including first and second multiplicative mixers connected from the respective outputs of said first pickup and said second source, said output means including first auxiliary means connected from said first source for impressing a first auxiliary alternating signal of said second frequency on said first mixer, said output means including second auxiliary means for impressing a second auxiliary alternating signal of said second frequency on said second mixer, said first and second auxiliary signals being 90* out of phase with each other, said output means including an adder connected from both of the outputs of said mixers.

Claim 18

Apparatus for producing a high resolution alternating output signal of a high frequency directly proportional to angular velocity, said apparatus comprising a base; a body rotatable on said base; an articulatEd ferromagnetic member fixed relative to said body, said articulated member including a ring of equally spaced ferromagnetic teeth fixed to said body in a position concentric with the rotational axis thereof; a first magnetic pickup fixed relative to said base in a position for cooperation with said member to produce a first alternating signal of a first frequency directly proportional to the angular velocity of said body; a first source of a second alternating signal of a constant second frequency; a second source of a third alternating signal of said first frequency operably synchronously with said first pickup, said third signal being 90* out of phase with said first signal; and output means connected from said first pickup and said second and third sources for producing a fourth alternating signal directly proportional to the difference between said first and second frequencies, said output means including first and second multiplicative mixers connected from the respective outputs of said first pickup and said second source, said output means including first auxiliary means connected from said first source for impressing a first auxiliary alternating signal of said second frequency on said first mixer, said output means including second auxiliary means for impressing a second auxiliary alternating signal of said second frequency on said second mixer, said first and second auxiliary signals being 90* out of phase with each other, said output means including an adder connected from both of the outputs of said mixers.

Claim 19

The invention as defined in claim 13, wherein said second source includes a second magnetic pickup angularly spaced from said first pickup and fixed relative to said base in a position for cooperation with said articulated member to produce said third signal.

Claim 20

The invention as defined in claim 14, wherein a frequency discriminator is provided that is responsive to the output of said adder.

Claim 21

The invention as defined in claim 13, wherein a frequency discriminator is provided that is responsive to the output of said adder.