Sliding Mode Observer with Gain Tuning Method for Passive Interferometric Fiber-Optic Gyroscope.

Area of Science:

• Optoelectronics
• Control Systems Engineering
• Inertial Navigation

Background:

• Interferometric fiber-optic gyroscopes (IFOGs) are crucial for measuring angular velocity.
• Passive IFOGs offer advantages by eliminating the need for optical phase modulators.
• Sliding mode observers (SMOs) are robust control techniques applicable to dynamic systems.

Purpose of the Study:

• To evaluate the performance of a sliding mode observer (SMO) for a passive interferometric fiber-optic gyroscope (IFOG).
• To demonstrate a passive IFOG implementation using a 3x3 directional coupler, avoiding phase modulators.
• To analyze the gain tuning method for the IFOG-SMO system.

Main Methods:

• Design and evaluation of an experimental setup generating two out-of-phase signals for the SMO.
• Implementation of a passive IFOG-SMO using a 3x3 optical fiber directional coupler.
• Simulations to analyze system gain dependence on sigmoid factor and sample rate.

Main Results:

• Successful operation of the passive IFOG-SMO system.
• Demonstrated capability to measure both large and small amplitude angular velocities.
• Expansion of the full-scale measurement range for the IFOG.

Conclusions:

• The developed passive IFOG-SMO system is effective for angular velocity measurement.
• This work represents the first reported evaluation of sliding mode control for IFOGs.
• The system offers a promising approach for passive IFOGs without phase modulators.