Abstract High sensitivity rotation rate measurement is accomplished by means of a magnetic surface wave Sagnac effect sensor. An annular or ring-shaped member constituting a magnetic surface transmission medium is combined with a closely proximate (but separate) electromagnetic wave/magnetic surface wave transducer. The annular member is in a fixed inertial frame and rotatable about its major axis. The transducer is in a fixed frame relative to rotation of the annular member and induces magnetic surface waves on the transmission medium in response to an electromagnetic wave input. A magnetic field producing means positioned in fixed relationship to the transmission medium effects both clockwise and counterclockwise flow of the magnetic surface waves. The transducer also produces electromagnetic wave signals in response to the clockwise and counterclockwise magnetic surface waves. Rotational movements of the annular member relative to the transducer effects a circulation time difference between the clockwise and counterclockwise magnetic surface waves. The resulting electromagnetic wave signals are detected and processed as a measure of the rotation rate of the annular member.
A magnetic surface wave rotation rate sensor comprising an annular magnetic surface wave transmission medium, said transmission medium being rotatable about its major axis and in a fixed inertial frame, magnetic field producing means positioned in fixed relationship to said transmission medium and adapted to induce clockwise and counterclockwise flow of magnetic surface waves propagating thereon, transducer means positioned in close proximity to said transmission medium and being in a fixed frame relative to rotation thereof, said transducer means being adapted to generate magnetic surface waves on said transmission medium in response to an electromagnetic wave input and to generate first and second electromagnetic wave output signals in response to clockwise and counterclockwise magnetic surface waves propagating on said transmission medium, a source of electromagnetic wave energy connected to said transducer means, and detector means connected to said transducer means adapted to process said first and second electromagnetic wave output signals as a measure of relative motion between said transmission medium and said transducer means.
Claim 2
Dependent Claim
165 words
A magnetic surface wave rotation rate sensor comprising an annular magnetic surface wave transmission medium, said transmission medium being rotatable about its major axis and in a fixed inertial frame, magnetic field producing means positioned in fixed relationship to said transmission medium and adapted to induce clockwise and counterclockwise flow of magnetic surface waves propagating thereon, transducer means positioned in close proximity to said transmission medium and being in a fixed frame relative to rotation thereof, said transducer means being adapted to generate magnetic surface waves on said transmission medium in response to an electromagnetic wave input and to generate first and second electromagnetic wave output signals in response to clockwise and counterclockwise magnetic surface waves propagating on said transmission medium, a source of electromagnetic wave energy connected to said transducer means, and detector means connected to said transducer means adapted to process said first and second electromagnetic wave output signals as a measure of relative motion between said transmission medium and said transducer means.
Claim 3
Dependent Claim
29 words
A magnetic surface wave rotation rate sensor as defined in claim 1 wherein said magnetic surface wave transmissioN medium comprises first and second juxtaposed concentric bands of ferrimagnetic material.
Claim 4
Dependent Claim
36 words
A magnetic surface wave rotation rate sensor as defined in claim 1 wherein said magnetic surface wave transmission medium comprises a circular domain wall defined in a ferrimagnetic sheet member by said magnetic field producing means.