针对目前大多数跳跃式再入制导方案在初次再入段采用数值预测⁃校正算法存在的计算量较大、在线应用困难的问题，提出了一种新的跳跃式再入标称轨迹制导方案。整条标称轨迹通过离线轨迹规划算法得到。在初次再入段，采用非线性预测控制算法来跟踪阻力加速度⁃能量剖面，将预测跟踪误差表示为依赖于控制量的截断泰勒展开式，然后寻找使得特定目标函数最小的控制量。进入二次再入段，采用类似于阿波罗末段制导的线性反馈跟踪方式，PID控制器系数通过插值得到。最后，在考虑各种误差的情况下进行了500次蒙特卡洛仿真，仿真结果表明制导律的精度较高，鲁棒性较好。%In most of the mature skip entry guidance schemes, such as PredGuid and NSEG for CEV reentry, numerical predictor⁃corrector algorithm is used for the guidance of the first entry phase. Nu⁃merical predictor⁃corrector algorithm is of high accuracy and is flexible and autonomous, but it is too computation intensive to be applied online. A new guidance scheme using a reference trajectory for skip entry was proposed in this paper. The whole reference trajectory was obtained by off⁃line trajec⁃tory planning algorithm. In the first reentry phase, a nonlinear predictive control algorithm is used to track the drag⁃versus⁃energy profile. The predicted tracking error was expressed as a truncated Tay⁃lor series dependent on the control. The control was then selected to minimize a cost function related to the predicted error. In the second reentry phase, the reference trajectory was tracked by a linear feedback control algorithm which was used in Apollo final phase. The gain coefficient of PID control⁃ler was obtained by interpolation. Finally, the new guidance scheme was tested by the simulation of 500 entry cases with all kinds of errors. Simulation results indicate that the new guidance has high accuracy and notable robustness.
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