An actuator system includes an actuator device comprising at least one piezoelectric member, a driving system, and an actuator controller. The driving system drives the at least one piezoelectric member at a driving frequency. The actuator controller monitors at least one parameter of the actuator device and the direct driving system to determine an operational mechanical resonant frequency of the actuator device based on the at least one parameter. The actuator controller adjusts the driving frequency based at least in part on the determined operational mechanical resonant frequency.