2. Main piezomotor structures

2.1 General principles

The operating principle of piezomotors is based on the exploitation of mechanical deformations generated by the piezoelectric (or even piezomagnetic) effect, to drive a moving part in translation or rotation. The uniform nature of the desired translational or rotational movement means that the energy conversion performed in the motor takes place in two stages. The electromechanical conversion provided by the piezoelectric transducer with alternating deformation must be accompanied by a purely mechanical conversion, aimed at transforming the initial vibratory motion into uniform motion. Since the micrometric amplitude of the vibrations involved means that traditional articulated mechanical links (e.g. a connecting rod and crank system) are not possible, this mechanical...