中点误差控制刀位算法的改进
|
摘要
中点误差控制刀位算法通过引入抬刀量的概念,将刀具抬离曲面极小的距离,然后调整前倾角与侧偏角以提高刀具与曲面的贴合程度来获得较大加工行宽。文中提出一种将刀触点处侧偏角进行预处理的方法,以避免因一行刀轨内侧偏角不光顺带来的刀轨波动问题。首先对曲面进行分析并选取采样点,然后对采样点处进行刀位优化算得最优侧偏角,以采样点处侧偏角值构造侧偏角二维渐变模型,通过该模型可以计算曲面上任意刀触点处的侧偏角,再通过优化抬刀量和前倾角实现刀触点处行宽最大化。以某航空发动机叶片叶身曲面为例进行了刀位优化。实验结果表明,该方法生成加工刀轨较光顺,证实了该算法的有效性。
Cutter lifting amount is introduced in middle-point-error-control tool path generation method in this paper.Cutter is lifted a tiny distance from the surface,the incline angle and tilts angle are adjusted to achieve a wider machining width.This paper presents a method which can pretreat tilt angle to avoid the fluctuation of tool path due to the nonsmooth tilt angle on tool path.Firstly,we analyze the surface and select the sample points,then calculate the optimal tilt angle via the optimization of tool position on sample points where the gradual model is established.By calculating the tilt angle on every tool position,the uplift amount and incline angle is well-optimized to gain the maximum width on the tool position.This method is verified through generating the smooth tool path of a blade of an aero-engine.
Cutter lifting amount is introduced in middle-point-error-control tool path generation method in this paper.Cutter is lifted a tiny distance from the surface,the incline angle and tilts angle are adjusted to achieve a wider machining width.This paper presents a method which can pretreat tilt angle to avoid the fluctuation of tool path due to the nonsmooth tilt angle on tool path.Firstly,we analyze the surface and select the sample points,then calculate the optimal tilt angle via the optimization of tool position on sample points where the gradual model is established.By calculating the tilt angle on every tool position,the uplift amount and incline angle is well-optimized to gain the maximum width on the tool position.This method is verified through generating the smooth tool path of a blade of an aero-engine.
引文
[1]JENSEN C G.ANDERSON D C.Accurate tool placement and orientation for finished surface[J].Machining J.Design and Manufacture,1993(3):251-261.
[2]KRUTH J P,KLEWAIS P.Optimization and dynamic adaptation of the cutter inclination during five-Axis milling of sculptured surfaces[J].CIRP Annals-Manufacturing Technology,1994,43(1):443-448.
[3]陈涛,钟毅芳,周济.自由曲面5轴数控加工刀位轨迹的生成算法[J].机械工程学报,2001,37(12):100-103.
[4]WARKENTIN A,BEDIS,ISMAILF.Five-axismilling of spherical surfaces[J].International Journal of Machine Tools and Manufacture,1996,36(2):229-243.
[5]WARKENTIN A,ISMAIL F,BEDI S.Multi-point tool positioning strategy for 5-axis machining of sculptured surfaces[J].Computer Aid Geometric Design,2000,17(1):83-100.
[6]WARKENTIN A,ISMAIL F,BEDI S.Comparison between multi-point and other 5-axis tool positioning strategies[J].International Journal of Machine Tools&Manufacture,2000,40:185.
[7]张洪.从增大行距宽度减少波纹度的角度看型面加工发展的方向[C]//型面加工与检测论文集,1982:7-11.
[8]倪炎榕,马登哲,张洪,等.圆环面刀具五坐标数控加工复杂曲面优化刀位算法[J].机械工程学报,2001,37(2):87-91.
[9]倪炎榕.环面刀具五坐标数控加工复杂曲面优化刀位计算与图形显示[D].北京:北京航空航天大学,1999:23-30.
[10]金曼.五坐标刀位优化端点误差控制算法研究[D].北京:北京航空航天大学,2006:26-41.
[11]金曼,张俐,陈志同,等.圆环面刀具五坐标加工端点误差控制刀位优化[J].北京航空航天大学学报,2006,32(9):1125-1128.
[12]王瑞秋,金曼,陈五一,等.端点误差控制刀位算法的改进[J].航空学报,2007,28(2):438-444.
[13]陈志同,乐毅,徐汝锋.中点误差控制宽行加工算法[J].机械工程学报,2011,47(1):117-123.
[14]乐毅.五坐标宽行加工的刀轨光顺技术研究[D].北京:北京航空航天大学,2007:37-40.
[15]徐汝锋,陈五一,陈志同.基于经线划分的非圆截面环形刀具刀位优化算法[J].航空学报,2010,31(2):410-417.
[16]倪小军.点云数据精简及三角网格面快速重构技术的研究与实现[D].苏州:苏州大学,2010:29-30.
[2]KRUTH J P,KLEWAIS P.Optimization and dynamic adaptation of the cutter inclination during five-Axis milling of sculptured surfaces[J].CIRP Annals-Manufacturing Technology,1994,43(1):443-448.
[3]陈涛,钟毅芳,周济.自由曲面5轴数控加工刀位轨迹的生成算法[J].机械工程学报,2001,37(12):100-103.
[4]WARKENTIN A,BEDIS,ISMAILF.Five-axismilling of spherical surfaces[J].International Journal of Machine Tools and Manufacture,1996,36(2):229-243.
[5]WARKENTIN A,ISMAIL F,BEDI S.Multi-point tool positioning strategy for 5-axis machining of sculptured surfaces[J].Computer Aid Geometric Design,2000,17(1):83-100.
[6]WARKENTIN A,ISMAIL F,BEDI S.Comparison between multi-point and other 5-axis tool positioning strategies[J].International Journal of Machine Tools&Manufacture,2000,40:185.
[7]张洪.从增大行距宽度减少波纹度的角度看型面加工发展的方向[C]//型面加工与检测论文集,1982:7-11.
[8]倪炎榕,马登哲,张洪,等.圆环面刀具五坐标数控加工复杂曲面优化刀位算法[J].机械工程学报,2001,37(2):87-91.
[9]倪炎榕.环面刀具五坐标数控加工复杂曲面优化刀位计算与图形显示[D].北京:北京航空航天大学,1999:23-30.
[10]金曼.五坐标刀位优化端点误差控制算法研究[D].北京:北京航空航天大学,2006:26-41.
[11]金曼,张俐,陈志同,等.圆环面刀具五坐标加工端点误差控制刀位优化[J].北京航空航天大学学报,2006,32(9):1125-1128.
[12]王瑞秋,金曼,陈五一,等.端点误差控制刀位算法的改进[J].航空学报,2007,28(2):438-444.
[13]陈志同,乐毅,徐汝锋.中点误差控制宽行加工算法[J].机械工程学报,2011,47(1):117-123.
[14]乐毅.五坐标宽行加工的刀轨光顺技术研究[D].北京:北京航空航天大学,2007:37-40.
[15]徐汝锋,陈五一,陈志同.基于经线划分的非圆截面环形刀具刀位优化算法[J].航空学报,2010,31(2):410-417.
[16]倪小军.点云数据精简及三角网格面快速重构技术的研究与实现[D].苏州:苏州大学,2010:29-30.