Abstract: Micromachined vibratory gyroscope and method in which the vibrating masses are coupled electronically, e.g. by electronically adjusting the resonance frequency of one or more of the masses so that all of the masses have the same resonance frequency.

Abstract: Inertial rate sensor and method in which a drive signal is applied to a rate sensing element, a pickup circuit is coupled to the rate sensing element for providing an output signal corresponding to movement of the rate sensing element, digital logic calibrates the rate sensor and detects the occurrence of faults in the rate sensor, the rate sensing element is utilized as a frequency reference for providing a system clock signal for the digital logic, a fixed phase relationship is maintained between vibration of the rate sensing element and the system clock signal, the system clock signal is filtered to eliminate responses to spurious transitions during a period following application of operating power to the sensor, and the digital logic is reset in synchronization with the system clock signal.

Abstract: Inertial rate sensor and method in which a drive signal consisting initially of a square wave and thereafter a sine wave is applied to a vibratory rate sensing element, a pickup circuit is coupled to the rate sensing element for providing an output signal corresponding to movement of the rate sensing element, the magnitude of the drive signals is adjusted to set a scale factor which determines the sensitivity to movement of the rate sensing element, and a signal in the drive circuit is monitored to detect a failure.

Abstract: Inertial rate sensor and method in which in which a single output terminal is utilized for delivering a rate output signal during normal operation, interfacing with an external computer during a programming mode, and for providing a warning in the event of a failure. Access to the programming mode is permitted only when a predetermined sequence of conditions is met, and accidental initiation of the programming mode is virtually impossible. Compensation data is stored redundantly at two locations in an internal memory, and the data is read from both locations and compared to verify its validity. Signals are monitored at different points to detect the occurrence of failures.

Abstract: An integrating voltage-to-frequency converter and method for converting a DSB-SC signal into a frequency-encoded signal. The DSB-SC signal is demodulated using an up/down counter, the count direction of which is alternatively switched in synchronism with the phase polarity of a reference carrier signal for the DSB-SC signal. The converter includes an integrator, a comparator, and means for rebalancing the integrator circuit. Means for tracking and storing a partial-bit analog signal level at the output of the integrator are provided, where the partial-bit analog signal level is obtained just prior to a phase transition of the reference carrier signal. The count of the up/down counter is corrected thereby to account for the partial-bit analog signal information.

Abstract: A DSB-SC signal is demodulated using an up/down counter, the count direction of which is alternately switched in synchronism with the polarity of a reference carrier signal for the DSB-SC signal. The converter includes an integrator, a comparator and a charge-rebalancing current source to reset the integrator. Correction of the court value of the up/down counter is obtained by tracking and storing a partial-bit analog signal. The partial-bit analog signal corresponds to and is obtained from the output of the integrator just prior to the pahse transition of the reference carrier signal. A capacitor samples the partial-bit analog signal information and subsequently transfers that information to the integrator input. The transfer of a charge of twice the magnitude and opposite polarity to the integrator compensates for the partial bit analog signal as it is detected by the up/down counter. A digital system for converting the partial-bit analog signal to a binary code word is provided.

Abstract: Servoed accelerometer with isolated voltage torquing having first and second grounds, a servoed accelerometer having a torque coil, and an amplifier for driving said torque coil. The amplifier has inverting and non-inverting junctions. The second ground is coupled to the non-inverting junction of the amplifier. A torque signal supply is coupled to the first ground. A transformer is provided for coupling the torque signal supply to the non-inverting junction of the amplifier and serves to isolate the torque signal supply from the non-inverting input of the amplifier so that the amplifier and polarity of the torque signal are preserved.

Abstract: The technique for replacing certain components in a linear accelerometer with an arrangement compatible with all of the other components making up the accelerometer is disclosed herein. The components that are replaced include a potentiometer and mechanical acceleration sensing means which cooperate with one another and which operate on a DC excitation voltage for producing an initial voltage dependent on both the acceleration sensed and the excitation voltage. The arrangement replacing these latter components include acceleration sensing means operating on the same DC excitation voltage for producing an initial voltage which is dependent on the acceleration but which is independent of the excitation voltage and means for adding a percentage of the excitation voltage to this latter voltage for providing a voltage which is dependent on both the acceleration sensed and the excitation voltage, thereby making the arrangement compatible with those components in the accelerometer which have not been replaced.