Abstract
This study presents a novel approach to static load measurement that addresses a limitation inherent to single piezoelectric elements. We propose a sensor design utilizing a piezoelectric vibrator constructed by bonding two identical piezoelectric elements; one element is excited at its resonant frequency, while the other generates voltage by responding to the induced vibration. When a load is applied to the sensor body, the external force significantly alters the mechanical impedance of the vibrator, causing a rapid drop in sensor voltage. However, the sensor voltage saturates very quickly with even a small load, resulting in an extremely limited measurable load range. To address this drawback, we developed a load application method using an elastic body with a load-dependent shape. This elastic body mediates the load application, causing the mechanical impedance of the vibrator to change gradually in response to increasing load. This approach allows for control over sensor voltage characteristics, including both measurement range and linearity.
