倾角约束条件下的机器人喷涂轨迹优化

Optimization of robot spraying trajectory under the constraint of tilt angle

目的:提高机器人针对自由曲面进行倾斜喷涂时的涂层厚度均匀性。方法:提出了一种以喷枪姿态和移动速度为变量的倾角喷涂轨迹优化方法。首先建立了喷枪倾斜喷涂时的涂层增长模型,然后用边界盒子法生成待加工面上的喷涂轨迹,并且采用插补的方法获得以涂层厚度均匀性为目标的喷涂轨迹优化模型,最后用改进的遗传算法求解获得每条轨迹上喷枪姿态和移动速度的最优值。结果:前两次仿真实验中,仅优化喷枪的移动速度,曲面上的涂层最大厚度差分别为34.0μm和54.0μm,而同时对喷枪的姿态和移动速度进行优化,涂层最大厚度差为5.6μm。结论:喷枪倾斜喷涂时,对喷枪姿态和移动速度同时进行优化,可以更好的提高涂层均匀性。

Aims: This paper aims to improve the uniformity of the coating thickness when the robot was sprayed at an angle on a free surface. Methods: A tilt spray trajectory optimization method with the variables of gun attitude and travel speed was proposed. A coating growth model was first constructed when the gun was sprayed at a tilt. Then the spray trajectory on the surface to be processed was generated using the boundary box method;and an interpolation method was used to obtain an optimized model of the spray trajectory with the goal of coating thickness uniformity. Finally, an improved genetic algorithm solution was used to obtain the optimal values of gun attitude and travel speed on each trajectory. Results: In the first two simulation experiments, only the travel speed of the gun was optimized and the results obtained were that the maximum coating thickness difference on the surface was 34.0 μm and 54.0 μm, respectively. However, when both the gun attitude and the travel speed were optimized, the maximum coating thickness difference was 5.6 μm. Conclusions: When sprayed at a tilt, better coating uniformity can be achieved if both the gun attitude and the travel speed are optimized.