Patent ID: 6553835
Filing Date: 2003-04-29
Classification: G01C

Abstract:
In an inertial rate sensor: a vibratory rate sensing element having a natural frequency of resonance, a drive circuit for applying a drive signal to the rate sensing element, a pickup circuit coupled to the rate sensing element for providing an output signal corresponding to movement of the rate sensing element, digital logic for calibrating the rate sensor and detecting the occurrence of faults in the rate sensor, means utilizing the rate sensing element as a frequency reference for providing a system clock signal for the digital logic, means for maintaining a fixed phase relationship between vibration of the rate sensing element and the system clock signal, means for filtering the system clock signal to prevent clock pulses from being generated in response to spurious transitions in a waveform from which the clock signal is derived, and means for resetting the digital logic in synchronization with the system clock signal.