Patent classifications
G01P15/132
ACCELEROMETER FORMING A RECESS ENCLOSING AN ELECTROMAGNETIC COIL
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.
VIBRATION RECTIFICATION ERROR CORRECTION CIRCUIT, PHYSICAL QUANTITY SENSOR MODULE, STRUCTURE MONITORING DEVICE, AND CORRECTION VALUE ADJUSTMENT METHOD OF VIBRATION RECTIFICATION ERROR CORRECTION CIRCUIT
A vibration rectification error correction circuit includes a first correction circuit that obtains a digital value based on a signal to be measured output from a sensor element configured to measure a physical quantity and corrects a vibration rectification error of the digital value by a correction function based on a product of values obtained by biasing the digital value.
High-precision magnetic suspension accelerometer
A high-precision magnetic suspension accelerometer for measuring the linear acceleration of a spacecraft is provided, comprising a magnetically shielded vacuum chamber system, a magnetic displacement sensing system, a magnetic suspension control system and a small magnetic proof mass. A optical coherence displacement detection technique is utilized for precisely measuring the position and the posture of the small magnetic proof mass in real time, and a magnetic suspension control technique is utilized for precisely controlling the position and the posture of the small magnetic proof mass to be brought back to the origin, so as to keep the small magnetic proof mass in the center of the systemic inner chamber. When the spacecraft is subject to a non-conservative force, the magnitude and direction of the acceleration can be precisely measured via the measurement of currents in the position control coils due to the acceleration of the spacecraft proportional to the currents of the position control coils. The accelerometer of the invention can avoid the technical bottleneck of high-precision machining, is easy to be produced and can achieve more high-precision measurement of the acceleration vector.
Accelerometer
Accelerometers as disclosed herein include a proof mass assembly and an accelerometer support. In some examples, a combined height and a combined coefficient of thermal expansion (CTE) of the materials of the accelerometer support is configured to substantially match a CTE of material of the non-moving member with a height substantially similar to the combined height of the accelerometer support. In some examples, the accelerometer support is configured to connect to a center raised pad of the proof mass assembly and maintain a capacitance gap between a capacitance plate on a proof mass of the proof mass assembly and a portion of the non-moving member.
VIBRATING-MASS GYROSCOPE SYSTEM
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.
High-precision pendulous accelerometer
Provided is a quartz pendulous accelerometer including a quartz meter configured to sense an acceleration signal, convert the acceleration signal into an inertia torque, and convert the inertia torque into a quartz meter output signal; a readout apparatus configured to convert the meter output signal into an input signal recognizable by a pulse generating apparatus; and a pulse generating apparatus configured to perform control algorithm conversion, oversampling and digital quantization on the input signal to obtain a quantized current pulse, which is converted into an electromagnetic pulse torque for balancing the inertia torque.
Reducing bias in an accelerometer via current adjustment
An accelerometer includes a first stator, a second stator, a proof mass assembly disposed between the first stator and second stator, and a controller. The first stator includes a first magnet and the second stator includes a second magnet. The proof mass assembly includes a first coil configured to receive a first amount of current and a second coil configured to receive a second amount of current. The controller is configured to distribute the first amount of current to the first coil and the second amount of current to the second coil. The first amount of current is different than the second amount of current.
Reducing bias in an accelerometer via a pole piece
An accelerometer includes an upper stator, a lower stator, and a proof mass assembly disposed between the upper and the lower stator. At least one of the upper stator or the lower stator includes an excitation ring, a magnet coupled to the excitation ring, and an asymmetric pole piece coupled to a top surface of the magnet. The asymmetric pole piece covers at least a portion of the top surface of the magnet such that a center of magnetic flux associated with the at least one of the upper stator or the lower stator is aligned with a center of mass of the proof mass assembly.
HIGH-PRECISION PENDULOUS ACCELEROMETER
Provided is an accelerometer, and particularly to a quartz pendulous accelerometer, including a quartz meter, which is configured to sense an acceleration signal, convert the acceleration signal into an inertia torque and convert the inertia torque into a quartz meter output signal; a readout apparatus, which is configured to convert the meter output signal into an input signal recognizable by a pulse generating apparatus; a pulse generating apparatus, which is configured to perform control algorithm conversion, oversampling and digital quantization on the input signal to obtain a quantized current pulse, where the quantized current pulse is converted into an electromagnetic pulse torque for balancing the inertia torque. By means of a circuit design and a system stability design of the present disclosure, digital feedback is realized while quantizing a feedback current is implemented. Negative feedback is realized by adopting an oversampling technique, so that the linearity, the dynamic precision etc. of a closed-loop system are realized. In addition, applying a SDM achieves quantized noise shaping so as to realize purposes of low noise and digital quantity output.
Reducing hysteresis effects in an accelerometer
In some examples, the disclosure describes an accelerometer having improved hysteresis effects, the accelerometer including a proof mass assembly including a proof mass, a support structure, and a flexure flexibly connecting the proof mass to the support structure to allow the proof mass to move about the plane defined by the support structure. Some examples may include at least one thin film lead including an electrically conductive material on the flexure, where the at least one thin film lead provides an electrical connection between an electrical component on the support structure and an electrical component on the proof mass, and where the at least one thin film lead comprises at least one of a yield strength greater than pure gold or a thermal expansion coefficient less than pure gold.