Introduction to piezo motors In todays world piezoelectric motors are used everywhere. Locks, cameras, medical applications such as fluid control… Their driving capabilities with high accuracy and speed are attractive to a great deal of todays industry. Here an overview will be given on the working principles of piezo motors and of some of the available piezo motors made by the larger companies.
Quasi-static and ultrasonic piezo motors Roughly, piezo motors can be divided in two groups; quasi-static and ultrasonic. Quasi-static is based on either the clamping principle or the inertial principle. In the clamping principle, the slider or rotor is passed on by two sets of clamping and driving actuators step by step. The set of actuators moving in the driving direction are the ones clamping the object, while the other set is moving backwards preparing for the next clamp moment.
Inertial principle of piezo motors The inertial principle is based on inertia and the difference between static and dynamic friction coefficients. During the first and slower phase of the movement, there is no slippage occurring. In the second phase, the actuator moves in the opposite direction with much greater speed causing the slider to slip due to its inertia
Ultrasonic piezo motors use resonant frequencies to move objects. They can also be divided into two groups: Standing wave and traveling wave.