A Coverage Path Planning Method with Reinforcement Learning Considering Manufacturing Process Uncertainty
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摘要: 机器人扫描测量系统在汽车质量检测领域获得广泛应用,尤其数模环境下基于仿生优化算法的视点采样与路径规划研究取得较大进展。然而,基于名义数模环境的路径规划结果难以适用实际不确定性检测环境。为此,本文提出基于改进的蒙特卡洛树搜索的视点自适应采样方法,在线生成工业机器人运动轨迹。通过车门内板案例的对比分析,验证本文方法的有效性,为实现不确定制造环境下工艺路径的在线规划提供理论依据。Abstract: The robotic scanning system has been widely used in the quality inspection field of automobiles, especially the studies of viewpoint sampling and path planning based on the genetic optimization algorithm in the model-based environment. However, the path planning results based on the nominal models are difficult to apply to the actual inspection environment. To address this problem, a viewpoint adaptive sampling method is proposed based on an improved Monte Carlo tree search, and industrial robot motion trajectories are planned online. Finally, the case of the car door inner panel was used to illustrate the effectiveness of the method.
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Key words:
- optical inspection /
- coverage path planning /
- manufacturing deviation /
- motion planning
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算法1: 蒙特卡洛树搜索(MTCS) 输入: 初始视点位置信息S0 输出: 根据当前节点的状态, 选择最佳子节点S0′ 1: create root node v0 with state S0 2: for i=1: max-iteration: 3: v←TreePolicy(v0) 4: Δ←SimulatePolicy(s(v)) 5: BackUp(v, Δ) 6: end for 7: S0′ ←BestChild(v0) 算法2:树策略(TreePolicy) 输入:当前节点v 输出:当前节点的子节点v′ 1:while v is not terminal: 2:if v is not fully expanded 3:choose v′ from untried s(v) 4:v′ satisfy f(S, a0, a1, …, ai-1) 5:Return (v′) 6:else 7:v′→BestChild(v) 8:Return(v) 算法3:回溯函数(BackUp) 输入:当前节点v,默认策略模拟结果Δ 输出:更新被选择的节点信息 1:while v is not empty: 2:N(v)←N(v)+1 3:Q(v)←Q(v)+Δ 4:v←parent of v 表 1 扫描仪参数
Table 1. Parameters of the scanner
参数 数值 DOF/mm [780, 1 010] FOV 0.330 6 可视角/(°) 60 近端视场 374×374 远端视场 500×500 表 2 基于两种方法的机器人运动时间对比
Table 2. Comparison result Inspection time for full coverage based on two methods
s 场景 方法 实验值 平均值 1 2 3 4 5 1 本文方法 20.57 19.81 20.03 20.60 21.12 20.43 GA 21.27 21.27 21.27 21.27 21.27 21.27 2 本文方法 20.36 20.52 20.32 20.91 20.65 20.55 GA 21.29 21.29 21.29 21.29 21.29 21.29 3 本文方法 21.80 20.27 22.70 21.47 22.43 21.73 GA 22.87 22.87 22.87 22.87 22.87 22.87 4 本文方法 19.29 21.60 20.18 19.67 19.09 19.97 GA 22.39 22.39 22.39 22.39 22.39 22.39 5 本文方法 21.80 21.70 21.72 21.16 21.67 21.61 GA 25.59 25.59 25.59 25.59 25.59 25.59 -
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