The path planning for high-speed unmanned surface vehicle raises more complicated requirements to reduce sailing time and save energy. In this article, a new predictive artificial potential field is proposed using time information and predictive potential to plan a smoother path. The principle of artificial potential field with vehicle dynamics and reachability in local minimum is studied. According to global and local path planning, the most state-of-the-art traditional artificial potential field and its drawback are analysed at first. Then we proposed predictive artificial potential field with three modifications: angle limit, velocity adjustment and predictive potential to improve the feasibility and flatness of the generated path. In addition, we compare the performance between traditional artificial potential field and predictive artificial potential field, where predictive artificial potential field successfully restricts the maximum turning angle, cuts short sailing time and intelligently avoids obstacle. From the simulation results, we also verify that predictive artificial potential field can solve concave local minimum problem and enhance the reachability in special scenario. Therefore, the more reasonable path generated by predictive artificial potential field reduces sailing time and helps conserve more energy for unmanned surface vehicle.

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In order to solve the problem of insufficient aerodynamic moment caused by thin air in the re-entry stage of hypersonic vehicle, this paper establishes an attitude angle model of hypersonic vehicle with reaction control system (RCS), and derives its affine linear model to decoupled the internal and external loop. According to the dead zone and saturation characteristics of RCS thruster, a control method to convert continuous moment into discrete switching instruction using pulse width modulation (PWM) is proposed. Since the number of thrusters is usually redundant, the installation matrix of thrusters in the body coordinate is established, and the command moment is coordinately distributed to the individual thrusters. Then a double-loop sliding mode controller (DSMC) is designed to achieve attitude stability and trajectory tracking. Finally, the simulation results show that DSMC has higher maneuverability, fewer thruster switches and stronger robustness to interference.