High-Precision Adaptive Predictive Entry Guidance for Vertical Rocket Landing

摘要

The vertical landing and recovery of rockets are now considered an important solution in the field of reusable launch vehicles. This paper focuses on guided atmospheric entry to reach an expected landing site before landing with powered descent. Using the characteristic of predictive algorithms that the onboard model can be changed easily, a new predictive entry guidance algorithm based on the dual-channel attitude control of a low-lift entry vehicle is proposed. Because the accuracy of the predictive guidance entirely depends on the discrepancies between the onboard dynamic model and the real environment while the rocket enters the atmosphere, an onboard adaptive identification method of aerodynamic deviation is added to decrease the methodological error. Simulation results show that the adaptive predictive entry guidance performance is no longer dependent on knowledge of aerodynamic and density dispersion. The adaptive aerodynamic fitting method repeatedly adapts the onboard model to varied environments in real time, decreasing the traditional predictive algorithms' guidance error from kilometer-to meter-scale precision.