Note: An improved low-frequency correction technique for piezoelectric force sensors in high-speed nanopositioning...

Area of Science:

• Sensor Technology
• Control Systems Engineering
• Nanotechnology

Background:

• Piezoelectric sensors offer high sensitivity but suffer from high-pass responses, limiting low-frequency control applications.
• Existing methods for low-frequency correction often introduce additional complexity and first-order responses.
• Integral control is challenging with piezoelectric sensors due to their inherent frequency limitations.

Purpose of the Study:

• To develop a simplified low-frequency correction method for piezoelectric sensors.
• To enable direct application of integral control for enhanced sensor performance.
• To demonstrate simultaneous damping and tracking control in nanopositioning stages.

Main Methods:

• Utilized the piezoelectric sensor as an electrical component within a filter circuit for low-frequency correction.
• Implemented a first-order response correction, avoiding second-order complexities.
• Defined the cut-off frequency based on the buffer circuit's input resistance.

Main Results:

• Achieved a simplified, first-order low-frequency response from the piezoelectric sensor.
• Successfully demonstrated simultaneous damping and tracking control.
• Validated the method's effectiveness in a high-speed vertical nanopositioning stage.

Conclusions:

• The proposed simplified method effectively overcomes the low-frequency limitations of piezoelectric sensors.
• This technique simplifies control system design by avoiding complex correction methods.
• The approach is suitable for high-performance applications like nanopositioning.