针对可重复使用运载器再入返回的标称轨迹跟踪问题,结合轨迹在线更新策略,设计了一种基于动态逆方法的轨迹跟踪控制律。通过改进闭环解析解提高了轨迹在线生成算法的精度和快速性,将生成的高度—速度剖面转化为阻力—速度剖面,并在跟踪标称轨迹过程中更新标称轨迹以消除航程跟踪误差的影响。为了跟踪阻力—速度剖面,基于动态逆理论设计了轨迹跟踪控制律,并引入积分环节消除稳态误差,实现了对标称轨迹的准确跟踪,且跟踪误差具有全局收敛性。仿真结果表明,该轨迹跟踪控制律具有良好的跟踪性能,能够提高再入制导系统的自适应性。
A dynamic inverse tracking control law of nominal trajectory for Reusable Launch Vehicle re-entry is designed based on on-board trajectory reconfiguration strategy. The closed-loop analytical solution is modified to improve both accuracy and rapidity of on-board trajectory generation algorithm. The r - V profile obtained by on-board trajectory generation is transformed into D - V profile for tracking. The nominal trajectory is regenerated and updated on line to eliminate the flight range error. A dynamic inverse tracking control law is designed while an integration element is introduced to eliminate the steady-state error. The nominal trajectory can be tracked precisely and the tracking error has global convergence. The numerical simulation shows that the proposed tracking control law has good tracking performance and the guidance system has adaptability to different re-entry missions.