Construction of Acceleration Sensor Using a Coupled Vibrator

We describe an acceleration sensor comprised of a detection structure constructed from a pair of adjacent vibration bars with resonance frequencies closely aligned to the drive resonance and which are connected to, and placed in opposite directions from each other, in the load direction. Using this structure, acceleration can be easily calculated by differential detection of the oscillation amplitude signals of each of the two vibration bars. The volume of the sensor is made of stainless steel (SUS304). The volume of the experimental sample is about $80\times 90\times 8$ mm3, and the resonance frequency and quality factor are about 770 Hz and 145, respectively. The sensor characteristics are measured using the gravitational field, and the acceleration is changed by rotating the sensor around the axis along the length of the vibrator.