Sounding rocket’s attitude control algorithm using higher order sliding modes with differential thrusting technique

Abstract

Focusing on improving the accuracy of ‘Kunpeng’ sounding rocket’s upper service platform, a higher order sliding mode controller with differential thrusting technique is proposed. Sliding mode control is a Lyapunov-based algorithm that provides global stability. Due to the insensitivity to unknown model uncertainties and external disturbances, it is suitable for improving the robustness and accuracy of the upper service platform. Higher Order Sliding Mode (HOSM) control is even more powerful than the classical sliding mode control. It can effectively reduce the chattering phenomenon by moving the switching to the higher derivatives of the control. Meanwhile, the differential thrusting technique can break the solenoid valve’s minimum pulse width limit. It fires opposite valves with slightly different durations to generate millisecond pulse force equivalently. The technique provides a necessary basis for achieving high-precision control. Three channel’s attitude controllers are designed based on the proposed algorithm. Finally, simulation shows that the controllers have achieved a better performance than the improved pseudo rate modulators used in ‘Kunpeng-1B’ sounding rocket. The simulation and statistical results demonstrate the effectiveness of the designed controllers.