On the feasibility of using measurements of charge and effective capacitance for simultaneous position and force self-sensing of piezoelectric actuators

In this study a new relationship between effective capacitance, position, and force of a piezoelectric actuator is presented. This relationship in combination with an existing constitutive relationship between charge, position, and force, can pave the way for simultaneous sensorless position and force identification. A test setup is built to study the feasibility of using the proposed relationship. Satisfying experimental correlation between effective capacitance, force, and position has been achieved using a second order Taylor series.