Study on Optimization Method of Skin Error in Mirror Machining via Real-time Compensation
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摘要: 针对传统的飞机蒙皮镜像加工误差补偿方法收敛速度慢, 在大进给高速加工中很难完成较好的补偿效果的问题, 提出了一种蒙皮镜像加工误差实时补偿优化方法。该方法基于双点弦截法, 借助超声波测厚仪前两次获得的蒙皮壁厚与程序切削深度, 计算下一点的补偿值, 并通过控制镜像铣补偿轴运动实现加工误差补偿, 有效的提升了飞机蒙皮镜像铣的补偿效果, 减小了加工误差。最后通过有限元仿真和试验证明了该方法的优越性, 最大加工误差降低了41.67%, 总体加工误差降低了41.96%。Abstract: Aiming at the traditional error compensation method for aircraft skin in mirror machining has slow convergence speed and is difficult to achieve good compensation effect in large feed high-speed machining, a real-time compensation optimization method for skin error in mirror machining is proposed. Based on the two-point chord section method, with the help of the skin wall thickness and program cutting depth obtained by the ultrasonic thickness gauge twice before, the compensation value of the next point is calculated, and the machining error compensation is realized by controlling the motion of the compensation axis in mirror machining, which effectively improves the compensation effect of the aircraft skin in mirror milling and reduces the machining error. Finally, the superiority of this method is proved by using the finite element simulation and experiment. The maximum machining error is reduced by 41.67%, and the overall machining error is reduced by 41.96%.
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Key words:
- aircraft skin /
- mirror milling /
- double point chord section method /
- error compensation
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表 1 精加工参数
参数 数值 参数 数值 转速 8 000 r/min 刀具直径 20 mm 进给 1 500 mm/min 刀具刃数 2 切削宽度 12 mm 刀具螺旋角 0 切削深度 0.5 mm 浮动支撑力 75 N 目标壁厚 1.5 mm 水压 250 kPa -
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