Integral force feedback control with input shaping: Application to piezo-based scanning systems in ECDLs

Area of Science:

• * Control Systems Engineering
• * Mechanical Engineering
• * Optical Engineering

Background:

• * Piezo-based scanning systems face challenges with hysteresis and dynamic behavior, limiting scanning speed.
• * Existing control methods struggle to fully address mechanical resonance and non-linearity.
• * Tunable external cavity diode lasers require high-speed, precise scanning for optimal performance.

Purpose of the Study:

• * To develop a hybrid control system integrating integral force feedback (IFF) and input shaping.
• * To overcome hysteresis and dynamic non-linearities in piezo-based scanning systems.
• * To increase the scanning speed of tunable external cavity diode lasers.

Main Methods:

• * Analysis of flexible hinges and piezoelectric actuators to establish a dynamic model.
• * Implementation of integral force feedback (IFF) using a force sensor and integral controller for damping.
• * Application of time-domain input shaping based on minimum-acceleration trajectory planning to control resonance.

Main Results:

• * Integral force feedback (IFF) effectively eliminated hysteresis in the scanning systems.
• * Mechanical resonance was significantly reduced, though initial residual vibrations were observed.
• * The hybrid IFF and input shaping approach demonstrated effectiveness in controlling non-linearity and resonance.

Conclusions:

• * The proposed hybrid control system successfully addresses limitations in piezo-based scanning.
• * Combining IFF with input shaping enhances system stability and performance.
• * The developed approach enables higher scanning speeds for applications like tunable lasers.