Machining Method for Coating on Huge Revolution Surfaces

Abstract

Abstract:

This paper proposed a real-time machining method, which processed the foam coating on the surface of aircraft to be uniform in thickness,and with thin wall aluminum easily deforming cylindrical tankage. Non-contact distance measuring sensor was placed before the cutter. NC cutter path could be generated directly from discrete measured data points obtained with the measuring sensor. The machining problem for the thin-walled workpiece that was easy to be deformed was solved. In the period of cutter come to the measured points, data points acquisition, data processing and NURBS interpolation calculation should be finished. NURBS fast fitting method, micro-line and NURBS mixed interpolation were proposed based on fitting errors to meet the real-time machining requirements. Finally, experimental results verified the effectiveness of the machining method.

Key words: coating machining; , NURBS; , measured data point; , tool path generation

摘要：

针对航天领域中某大型易变形薄壁工件旋转曲面表面的涂层仿形加工问题，提出一种高效的实时加工方法。将距离传感器安装于刀具前方一定角度处，加工时，传感器先检测金属曲面外形数据，以测量的离散数据点计算刀具进给轨迹进而控制刀具进给，从而实现高效率的涂层加工，解决易变形薄壁工件表面涂层的仿形加工难题。在实时加工点到达测量点的时间段内，系统完成数据采集、数据处理和刀具轨迹计算。为提高运算实时性，提出对NURBS曲线进行近似拟合的轨迹快速生成方法，以拟合误差为依据将轨迹分成NURBS曲线段和折线段，在误差大的拟合点以直线段连接。最后，通过加工实验证明该加工方法高效、实用。

关键词: 涂层加工, NURBS, 测点数据, 刀轨计算

CLC Number:

TP391.7

Chen Zhihong, Fang Hairong, Fang Yuefa. Machining Method for Coating on Huge Revolution Surfaces[J]. China Mechanical Engineering, 2014, 25(23): 3195-3199,3238.

陈志鸿, 房海蓉, 方跃法. 大型旋转曲面表面涂层仿形加工方法[J]. 中国机械工程, 2014, 25(23): 3195-3199,3238.

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