High Precision Attitude Control Technology of Vertical Landing Returning Rocket

Aiming at the control difficulties in the recover phase of a vertical landing of returning rocket, such as static unstable shape, elastic deformation of large slenderness ratio arrow body, liquid storage phenomenon for zero-pole, large interference of sudden change of aerodynamic shape during the deployment of landing, large-scale attitude adjustment, etc. Requirements and constraints of the critical vertical landing phase on the control system are analyzed comprehensively in this paper. Moreover, a high-precision attitude control scheme for vertical landing phase is put forward, that include parametric optimization design for large static instability and slosh-polar zero structure, nonlinear smooth gain scheduling, and high precision attitude control algorithm based on ESO. Simulations show that the design requirements can be accomplished by schemes proposed.