Abstract: A novel active disturbance rejection control method is proposed to satisfy the high requirement of speed, accuracy and robustness of attitude control system for kinetic energy interceptor in space interception mission. Firstly, the attitude dynamics model of the kinetic energy interceptor is established and converted into the second order state equation of attitude tracking error. Secondly, based on the idea of small error, large gain and large error, small gain, a new nonlinear function is designed. Then, the tracking differentiator, the extended state observer and the nonlinear controller are respectively designed based on the nonlinear function. By taking the prescribed performance function that converges at a specified time as the expected signal of the tracking differentiator, the attitude error can converge to the expected value according to the prescribed performance function, and the convergence time can be predetermined. Finally, the pseudo rate pulse modulator is used to pulse the continuous control torque. Numerical simulations demonstrate that the proposed control method exhibits precise attitude control and robust resilience against external disturbances.

Key words: kinetic energy interceptor, nonlinear function, active disturbance rejection control, pseudo rate pulse modulator