Energy-optimal Path Planning Algorithm for Unmanned Surface Vessel Based on Reinforcement Learning
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摘要: 针对无人水面艇路径规划时存在洋流、障碍物等外部干扰的问题, 提出一种改进的基于强化学习的无人水面艇能耗最优路径规划算法。首先, 建立多个随机涡流组成的二维洋流模型和无人水面艇平面运动学模型; 其次, 依据洋流和无人水面艇相对速度关系, 计算路径点是否可达; 然后, 利用改进的奖励函数、动作集和状态集求解全局最优路径, 并采用B样条法进行平滑; 最后, 在2种典型环境下进行了数值仿真。仿真结果表明,该算法可规划出一条能耗最优且平滑的路径, 验证了算法的有效性和最优性。Abstract: To address path planning for unmanned surface vessels(USVs) in ocean environments affected by physical disturbances, such as ocean currents and obstacles, an energy-optimal algorithm based on improved reinforcement learning is proposed. First, a two-dimensional ocean-current model comprising multiple random vortices and a plane kinematic model of the USV is established. Then, the study determined whether a waypoint is reachable using the relative velocity relationship between the USV and the ocean current. An improved reward function, an action set, and a state set are used to obtain a global optimal path, and the B-spline method is applied to smooth the plan. Finally, numerical simulations are performed in two typical environments. The simulation results show that a path with optimal energy consumption and smoothness can be planned based on the proposed algorithm.
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表 1 仿真结果对比
Table 1. Comparison of simulation results
环境 算法 时间/s 大转向角个数 路径长度/m 情况1 直接路径 224 0 378 粒子群算法 207 3 453 传统算法 228 3 583 文中算法 183 0 454 情况2 直接路径 224 0 378 粒子群算法 217 1 428 传统算法 242 7 588 文中算法 191 0 451 -
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