Systems and methods are disclosed for generating temperature compensated acceleration data in analog and digital format from a torque balance accelerometer (TBA). During manufacture of the TBA, a calibration process is used for measuring a TBA scale factor and offset. After collecting scale and offset data, said data is loaded into the memory of the TBA. Field operation of the device includes: sensing a current temperature, retrieving the closest scale and offset correction factors from memory of the TBA, and performing linear interpolation to generate a temperature-compensated output for the TBA.

A magnetic circuit assembly for an accelerometer includes an excitation ring that includes a base portion defining oppositely facing first and second sides, a ring portion extending from the second side of the base portion to define a ring recess, a first metallic inlay recessed into the first side of the base portion in which the first metallic inlay includes a material different than that of the base portion, a second metallic inlay recessed into the second side of the base portion in which the second metallic inlay includes a material different than that of the base portion, and a magnet received within the ring recess and attached to the second metallic inlay.

Systems and methods are disclosed for generating temperature compensated acceleration data in analog and digital format from a torque balance accelerometer (TBA). During manufacture of the TBA, a calibration process is used for measuring a TBA scale factor and offset. After collecting scale and offset data, said data is loaded into the memory of the TBA. Field operation of the device includes: sensing a current temperature, retrieving the closest scale and offset correction factors from memory of the TBA, and performing linear interpolation to generate a temperature-compensated output for the TBA.

One embodiment includes a gyroscope system. The system includes a sensor system comprising a vibrating-mass and electrodes each arranged to provide one of a driving force and a force-rebalance to the vibrating-mass in each of three orthogonal axes. The system also includes a gyroscope controller that generates a drive signal provided to a first electrode of the electrodes to provide the driving force to facilitate an in-plane periodic oscillatory motion of the vibrating-mass along a first axis of the three orthogonal axes. The gyroscope controller also generates a force-rebalance signal provided to each of a second electrode and a third electrode of the plurality of electrodes associated with a respective second axis and a respective third axis of the three orthogonal axes to calculate a rotation of the gyroscope system about the respective second axis and the respective third axis of the three orthogonal axes.

The present disclosure discloses a vertical superconducting magnetic mass-spring oscillator with an adjustable natural frequency, comprising: a proof mass, a negative-stiffness superconducting coil and a positive-stiffness superconducting coil; the negative-stiffness superconducting coil is mounted at an opening of a semi-closed space of the proof mass, so that a part of magnetic lines of the negative-stiffness superconducting coil are in a compressed state in a closed space of the proof mass, and the other part of the magnetic lines of the negative-stiffness superconducting coil are in an expanded state outside the closed space of the proof mass; a vertical magnetic repulsive force applied to the proof mass by the negative-stiffness superconducting coil varies with a displacement of the proof mass from an equilibrium position, with the variation magnitude proportional to the displacement and the variation direction the same as the displacement direction; and the positive-stiffness superconducting coil is mounted in the semi-closed space of the proof mass, and a vertical magnetic repulsive force applied to the proof mass by the positive-stiffness superconducting coil varies proportionally to the displacement of the proof mass from the equilibrium position, with the variation direction opposite to the displacement direction. The present disclosure realizes that the natural frequency of the superconducting mass-spring oscillator is adjustable, and meanwhile, the cross-coupling effect of horizontal and vertical degrees of freedom of the proof mass can be reduced.

A magnetic circuit assembly for an accelerometer includes an excitation ring that includes a base portion defining oppositely facing first and second sides, a ring portion extending from the second side of the base portion to define a ring recess, a first metallic inlay recessed into the first side of the base portion in which the first metallic inlay includes a material different than that of the base portion, a second metallic inlay recessed into the second side of the base portion in which the second metallic inlay includes a material different than that of the base portion, and a magnet received within the ring recess and attached to the second metallic inlay.

A method for rebalancing a group of accelerometers in a gravity gradiometer instrument (GGI) includes the steps of defining and implementing a number of groupwise actuation constrainment modes based on a design of the gravity gradiometer instrument and its accelerometers. Implementing one constrainment mode comprises differentially scaling and distributing a single electrical current to multiple accelerometers' rebalance circuitry to cancel a specific acceleration effect experienced by the group of accelerometers or gradiometer as a whole. Superposition of a number of such modes enables rebalancing the full acceleration environment experienced by the group of accelerometers, given negligible local differential acceleration effects specific to, say, an individual accelerometer of the assembly. Mathematically, the multiple of constrainment modes are encapsulated by an actuation or constrainment modal influence matrix, arranged one mode per column of the matrix, and the electrical currents of respective modes are encapsulated in a vector listing of currents.

An example transducer includes an upper magnetic circuit assembly including an upper excitation ring, a lower magnetic circuit assembly including a lower excitation ring, and a proof mass assembly positioned between the upper and lower magnetic circuit assemblies. A coefficient of thermal expansion (CTE) of the proof mass assembly is lower than a CTE of each of the upper and lower excitation rings. The transduces also includes an outer support structure coupled to an outer surface of each of the upper and lower excitation rings, and the outer support structure includes at least one cutout configured to reduce a circumferential stiffness of the outer support structure.

An example accelerometer includes a first excitation ring comprising a first material having a first coefficient of thermal expansion (CTE), a second excitation ring comprising the first material having the first CTE; and a proof mass assembly disposed between and in contact with the first excitation ring and the second excitation ring. The proof mass assembly comprises a second material having a second CTE, wherein a difference between the first CTE and the second CTE is equal to or less than 0.5 parts per million per degree Celsius (ppm/ C.).

In some examples, an accelerometer system includes a first excitation ring comprising: a first housing; and a first cover removably attached to the first housing, wherein the first housing and the first cover define a first recess. The accelerometer system also includes a second excitation ring comprising: a second housing; and a second cover removably attached to the second housing, wherein the second housing and the second cover define a second recess. The accelerometer system also includes a proof mass assembly; and processing circuitry located within one or both of the first recess and the second recess, wherein the first excitation ring and the second excitation ring shield the processing circuitry from harmful levels of radiation existing outside of the accelerometer system, and wherein the processing circuitry is configured to maintain a proof mass of the proof mass assembly in a null position.