Modeling and active disturbance rejection controller design of spin missiles

Missile spins can reduce the disturbance caused by asymmetric body, the eccentric of mass and other problem, and can also lead to the attitude control of missile being more complicated. Dynamic model of a spin missile is established in quasi-body coordinates. The system is divided into inner and outer subsystems through time-scale separation principle. And the controllers of inner loop and the outer loop are both designed by the active disturbance rejection controller (ADRC). The main idea of ADRC is putting the uncertainty of the model, parameters perturbation and unmodelled dynamic as a system of total disturbance, and observing it through the extended state observer, and compensating to system timely. Simulation shows that the system in the conditions of parameters change and disturbance exist can maintain a good dynamic performance.