Study on dual rate-loop cascade control for LOS stabilization of gyro inertia platform

Considering the shortcomings of single rate-loop servo control composed of rate gyro for LOS stabilization of opto-electronic tracking system, a dual rate-loop cascade control structure is presented, which uses the DC tachometer to constitute the analog inner loop, and the rate gyro to constitute the digital outer loop. The functions of rejecting friction disturbance and insulating carrier turbulence are designed respectively. The system performances of disturbance rejection and robustness are analyzed and compared with single rate-loop control. The inner loop adopts PI algorithm and the outer loop adopts a time optimal self-tuning PID algorithm. The experimental results show that the proposed method reaches the system required stability, reduces error and reduces carrier disturbance under certain gyro noise level and acceleration sensitivity.