Gyro Sensor Operation:
The internal control electronics of the sensor maintain a constant set frequency which is
applied to the oscillation elements causing a calculated vibration to occur. The frequency is
also simultaneously monitored by the phase detector.
The vibration passes up to the pick-up elements of the tuning fork causing them to vibrate
and be suspended in a free floating state, easily influenced by rotational movement.
When the vehicle turns, the free-floating upper ends of the tuning fork flex. This generates a
millivoltage signal proportional to the turn.
The signal amplifier receives the signal and passes it on to the phase detector which com-
pares it to the original set frequency.
The phase detector determines what direction the vehicle has turned and passes the result
on to the frequency filter.
Since the piezo gyro sensor is also picking up other vibrational movements in the vehicle, the
frequency filter isolates the pertinent yaw signals and provides a DC voltage signal proportional
to the left/right turning movement of the vehicle.
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On-Board Monitor and Navigation Systems