Time-Synchronized Attitude Tracking Control for a Hypersonic Re-Entry Vehicle System With System Uncertainties and Disturbances

The dynamic and complex nature of hypersonic re-entry vehicle (HRV) systems poses significant challenges in achieving precise attitude control, especially when confronted with system uncertainties and disturbances. In addressing these challenges, the proposed study concentrates on devising and applying a time-synchronized attitude tracking control strategy. By introducing a time-synchronized convergence (TSC) strategy, the aim is to ensure that the attitude states of the HRV can be precisely tracked within fixed time constraints. Furthermore, the strategy is designed to attain the simultaneous convergence of all state variables to the origin, effectively mitigating the interrelated coupling challenges encountered in the system. To address the problem of system uncertainties and disturbances, a time-synchronized disturbance observer (TSDOB) is proposed. In addition, the TSC method also ensures that the direction of the control command remains consistently opposite to the system state without generating any redundant motion components in other directions, thereby reducing excess energy consumption. The rigorous stability analysis for the time-synchronized stable (TSS) of the HRV system is demonstrated. In the end, simulations comparing fixed-time stable and TSS are conducted to validate the benefits of the proposed control method.