Sensitivity of Piezoelectric Stack Actuators

Area of Science:

• Mechanical Engineering
• Materials Science
• Electrical Engineering

Background:

• Piezoelectric actuators exhibit nonlinear hysteresis, complicating their dynamic analysis.
• Understanding actuator sensitivity is crucial for precise control and application design.

Purpose of the Study:

• To investigate the sensitivity of a mass-attached piezoelectric stack actuator.
• To analyze the nonlinear dynamics and develop an analytical model for piezoelectric actuators.

Main Methods:

• Defining sensitivity as the force spectrum output from a single-frequency voltage input.
• Modeling nonlinear dynamics as a cascade of nonlinear hysteresis and linear mechanical subsystems.
• Deriving analytical solutions for nonlinear differential equations.

Main Results:

• Nonlinear transformation maps single-frequency input to multiple-frequency output (driving frequency and odd harmonics).
• Steady-state sensitivity depends on the mechanical subsystem's response to the force spectrum.
• Maximum sensitivity occurs near the mechanical subsystem's natural frequency.

Conclusions:

• The proposed analytical model accurately describes piezoelectric actuator nonlinear dynamics.
• The model is validated by numerical simulations and experimental data.
• This framework aids in the analysis and design of various piezoelectric actuator configurations.