Study on attitude tracking and active vibration suppression of a flexible spacecraft based on fractional order sliding mode control

A complex controller is proposed for flexible spacecraft attitude tracking control, in which the advantages of fuzzy adaptive scheme, fractional control, sliding mode control, and active vibration compensation are all combined. First, a general nonlinear system form with the integrated disturbance is deduced from the traditional flexible spacecraft attitude control model. The integrated disturbance is approximated by the fuzzy adaptive theory and the universal approximation. A fractional order sliding mode controller is designed by the fractional order control theory and the sliding mode control, and the stability of the whole system is proved by Lyapunov theory and fractional stability theory. Second, a flexible mode compensator with strain rate feedback is given for flexible mode of spacecraft based on the control method of piezoelectric intelligent materials. Finally, numerical simulations are carried out to verify the analytical results and the effectiveness of the fuzzy adaptive fractional sliding mode controller.