Systems and methods for obstructing magnetic flux while shielding a protected volume

An apparatus configured for substantially obstructing at least one magnetic flux path between an ambient space and a protected volume, the protected volume being capable of containing a navigation grade nuclear magnetic resonance gyroscope, the apparatus comprising:

• an inner shield, substantially three-dimensionally enclosing the protected volume in order to prevent passage of magnetic flux to the protected volume;
• an outer shield, substantially three-dimensionally enclosing the inner shield in order to prevent passage of magnetic flux to the protected volume;
• and
• a wiring board located adjacent to and outside at least one of the inner and outer shielding means, wherein the wiring board is configured to provide an electrical connection to the protected volume while impeding magnetic flux between the ambient space and the protected volume in order to protect the navigation grade nuclear magnetic resonance gyroscope, when located in the protected volume, from magnetic fields, such that an orthogonal external magnetic field penetrates the apparatus to reach the protected volume at less than five parts per million of an applied internal magnetic field within the protected volume.

A method of substantially obstructing at least one magnetic flux path between an ambient space and a protected volume, the protected volume being capable of containing a navigation grade nuclear magnetic resonance gyroscope, the method comprising:

• substantially three-dimensionally enclosing the protected volume within an inner shield, the inner shield having at least one inner shield aperture extending therethrough in order to allow external access to the protected volume, in order to prevent passage of magnetic flux to the protected volume;
• substantially three-dimensionally enclosing the inner shield within an outer shield, the outer shield having at least one outer shield aperture extending therethrough in order to allow internal access from the ambient space, in order to prevent passage of magnetic flux to the protected volume;
• and
• impeding magnetic flux between at least one inner shield aperture and at least one outer shield aperture in order to protect the navigation grade nuclear magnetic resonance gyroscope, when located in the protected volume, from magnetic fields, such that an orthogonal external magnetic field reaches the protected volume at less than five parts per million of an applied internal magnetic field within the protected volume.

A system configured for substantially obstructing at least one magnetic flux path between an ambient space and a protected volume, the protected volume being capable of containing a navigation grade nuclear magnetic resonance gyroscope, the system comprising:

• an inner shielding means, substantially three-dimensionally enclosing the protected volume in order to prevent passage of magnetic flux to the protected volume, the inner shielding means having at least one inner shield aperture extending therethrough in order to allow external access to the protected volume;
• an outer shielding means, substantially three-dimensionally enclosing the inner shielding means in order to prevent passage of magnetic flux to the protected volume, the outer shielding means having at least one outer shield aperture extending therethrough in order to allow internal access from the ambient space;
• and
• obstruction means impeding magnetic flux between at least one inner shield aperture and at least one outer shield aperture in order to protect the navigation grade nuclear magnetic resonance gyroscope, when located in the protected volume, from magnetic fields, such that an orthogonal external magnetic field penetrates the apparatus to reach the protected volume at less than five parts per million of an applied internal magnetic field within the protected volume.