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This paper presents a skip entry guidance algorithm that uses a numerical predictor–corrector and a patched corridor for low-lifting capsules returning from the Moon. The longitudinal and lateral channels are assumed to be decoupled. The bank angle magnitude profile is parameterized using piecewise linear segments with respect to a normalized energy. The shape of the bank-vs-energy profile is determined using a single piecewise-defined variable. The predicted longitudinal bias is nullified using a false position method. The adverse effects of aerodynamic and atmospheric uncertainties are mitigated using an on-board estimating strategy during the trajectory prediction. A patched corridor is devised to manage the lateral state based on analytical derivations and reasonable approximations. The sign of the bank angle is reversed when the boundary of the patched corridor is violated. Dispersed simulations are implemented in a three-degree-of-freedom dynamical context, and the results demonstrate the high performance of the proposed guidance algorithm under stressful testing conditions. [ABSTRACT FROM AUTHOR]

This paper investigates the synchronization problems of multiple reaction–diffusion memristive neural networks (MRDMNNs) with known or unknown parameters and switching topologies via distributed control. In complex environment, the proposed system may face switching topologies, diffusion effects, external disturbance, parameter mismatch or uncertainty, so designing security control laws to synchronize the proposed system is a enormous challenge. The parameter mismatch terms herein are extended to be unbounded, which is different from the general boundedness hypothesis. Since the parameter mismatch term would be known or unknown, we design a novel parameter-dependent controller for the known condition and a novel parameter-independent adaptive controller for the unknown condition respectively. By constructing new Lyapunov functions, using some properties of M-matrix and robust control method, the synchronization errors will all converge into a bound set via the two designed nonlinear controllers. And we are able to select appropriate control parameters to control the upper bound. Moreover, the obtained theorems can determine the feedback control gains, which can be used for security control. Finally, two numerical simulations are given to support the obtained theoretical results. [ABSTRACT FROM AUTHOR]