Precise attitude control of multirotary-joint solar-power satellite

A filtered hyperbolic tangent switching iterative learning control is proposed to obtain high-precision attitude tracking control of multirotary-joint solar-power satellite. Simulations are carried out considering the effects of gravity gradient torque, solar radiation pressure, microwave reactive torque, and measurement noise. According to simulation results, the proposed controller can reduce the periodic attitude errors by about 25 times smoothly and adapts to the slow variation of the sun direction. Nonperiodic disturbance and measurement noise from the previous period are filtered out successfully by the filter. Furthermore, the sensitivity of the proposed controller to measurement noise is reduced greatly by reducing the weights of feedback control.