Global exponential attitude tracking for spacecraft with gyro bias estimation

Area of Science:

• Spacecraft attitude dynamics and control
• Nonlinear observer design
• Robust control systems

Background:

• Spacecraft attitude tracking is crucial for mission success.
• Gyro sensor bias and measurement noise degrade performance.
• Existing controllers face topological constraints and unwinding issues.

Purpose of the Study:

• To develop a robust global attitude tracking controller for spacecraft.
• To accurately estimate and compensate for gyro sensor bias.
• To improve robustness against measurement noise and prevent the unwinding phenomenon.

Main Methods:

• Contraction analysis for global stability.
• Nonlinear observer for exponential bias estimation.
• Exponentially convergent attitude tracking controller with bias correction.
• Switching variable with hysteresis to remove topological constraints.

Main Results:

• The proposed controller achieves exponential convergence for attitude and bias estimation.
• Demonstrated robustness against measurement noise and time-varying bias.
• Enhanced energy efficiency by preventing the unwinding phenomenon.
• Simulations show superior performance compared to existing methods.

Conclusions:

• The developed controller effectively addresses global attitude tracking under biased measurements.
• The integration of a nonlinear observer and hysteresis switching enhances system reliability.
• This approach offers a significant improvement for spacecraft attitude control applications.