根据水面无人艇运动学和基础控制特性提出一种局部危险规避算法. 采用分层策将动态窗口分解为艏向窗口和线速度窗口，使用切线法和弧线法分别从艏向窗口和线速度窗口中求出规避角速度和线速度，并引入角速度缓冲模型以提升规划过程中艇体的稳定性. 仿真实验验证了算法具有规避能力强和稳定性高的特点，并由湖试实艇实验验证了算法对实艇的基础控制特性具有良好的适应性，能引导水面无人艇在实际环境中实现有效安全的危险规避.
This paper proposes a local obstacle avoidance algorithm for unmanned surface vehicles (USV).It is designed based on the kinetic and basic motion control characteristics of USV. The heading window and linear velocity window are obtained from the dynamic window by using a hierarchical strategy. The angular
velocity and linear velocity are obtained from the heading window and linear velocity window with the tangent method and the curve method. For stability of the vessel, a buffering model of angular velocity is designed. Simulation shows that the proposed algorithm has strong capability of obstacle avoidance and high stability.Results of on-boat experiment demonstrate that the algorithm is suitable for the basic control of actual boats,and can guide USV to realize obstacle avoidance in real environment.
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