A force balanced instrument, such as an accelerometer, employs a pendulous mass having combined electrostatic pickoff and forcing plates on opposite sides thereof. The plates provide a constant attractive force in successive periods acting alternatively on opposing sides of the sensitive element. Force balance is achieved by controlling the duty cycle so that the difference in duration between each of the parts of a full cycle is a linear measure of acceleration. Voltage on each of the forcing plates is sensed independently immediately after each is charged with a fixed charging pulse which provides a fixed force level aver the duration of the part cycle. The two successive voltage simples are stored, and the difference between them integrated to control the duty cycle of a pulse width modulator, which itself controls the duration of application of the alternately directed forces applied by the respective plates to the pendulous mass.

Force balance instrument with electrostatic charge control

A rotation rate sensor is described that operates on the principle of a resonant vibration gyrometer and is excited by an amplitude-regulated oscillator loop. This sensor is used for instance to ascertain the yaw speed of a vehicle. The effect of Coriolis acceleration is evaluated, which is a measure for the current yaw speed. To monitor the operability of the sensor and the associated electronics, an integrated self-test function is used, which as a so-called BITE function introduces a defined interference variable after actuation of a test input. This defined interference variable leads to an estimatable output voltage, whose occurrence is evaluated for error detection.

Device for ascertaining a rate of rotation

A signal validation system measure direct current drift and noise in sensor signals from redundant sensors utilizing a parity-space algorithm. Parity vector signals produced by the parity-space algorithm are averaged to provide a direct current (DC) drift signal. An instantaneous noise signal is found by subtracting the direct current drift signal from a parity vector signal for one of the samples of the sensor signals. The RMS value of the instantaneous noise signals are averaged to provide sensors noise signals

System for determining dc drift and noise level using parity-space signal validation

Certain embodiments of the invention may include systems, methods, and apparatus for detecting shifts in redundant sensor signals. According to an example embodiment of the invention, a method is provided for detecting and indicating a shift in redundant sensor signals. The method can include receiving a sensor channel closeness signal for two or more redundant sensors, receiving a spike confidence signal for at least one of the two or more redundant sensors, receiving a spike duration signal for the at least one of the two or more redundant sensors, determining a shift confidence based at least in part on the received sensor channel closeness signal, the received spike confidence signal, and the received spike duration signal, and outputting the shift confidence.

Systems, methods, and apparatus for detecting shifts in redundant sensor signals

The present invention provides an electro-static floating type gyro device comprising: a gyro mechanism having a gyro rotor and plural adjacent pairs of electro static support electrodes for supporting said gyro rotor; a posture control circuit for generating complementary posture control voltages for controlling a posture of the gyro rotor, wherein the complementary posture control voltages applied to the adjacent pairs of electro static support electrodes are alternated in time.

Electro-static floating type gyro device

The rotor suspension electronics of an electrostatic gyro suspension system is required to perform flawlessly to sustain the life of the gyro Transient abnormalities as short as one millisecond duration will cause the spinning rotor to come in contact with the surrounding electrodes and result in destruction of the gyro Thus, not infrequently after a catastrophic dropped rotor incident no trace of the fault is evident upon ensuing check of the system To remedy this problem a built in test (BIT) system is used to provide fault isolation The test circuitry is built into the navigation system electronics and integrated with the system program The fault isolation electronics comprise sensor circuits to monitor functional subdivisions of the electronic suspension system for signal abnormality and a processing circuit which receives the sensor circuit outputs and identifies the primary source of the fault The faults are detected and the source is flagged at the time of occurance The output of the fault isolation electronics is a latched coded readout which is fed to the nagivation computer for memory storage and any appropriate follow-up system action, such as power shutdown After initialization by the computer, the fault isolation function is an automatic operation by the electronic circuitry

Paul H. Ito

Papers

Transient test of suspension electronics for gyroscope