Piezoelectric actuator with traveling wave waveguide

A novel design of traveling wave piezoelectric actuator with a special waveguide is investigated in the paper. Actuator consists of cylinder type waveguide and piezo ceramic ring. Waveguide has conical hole inside. Such configuration of the waveguide allows increasing amplitudes of the traveling wave vibrations. Electrodes of piezoceramic ring are divided into four equal sections. Four electric signals with shifted phases byπ/2 are used for the excitation. Numerical simulation was carried out to optimize the shape and dimensions of the waveguide and to maximize oscillation amplitudes at the contact surface of the waveguide. Mathematical model of the contact interface between stator and rotor was developed. A prototype piezoelectric actuator was made and experimental investigation was performed. Results of numerical and experimental investigation are discussed.