Positioning Algorithm for 5-axis Machining of
Ruled Surfaces Based on Radius and Angle Offset

XI Guang¹  WU Guangkuan^{1, 2}  ZHENG Jiansheng¹

(1. School of Energy & Power Engineering, Xi’an Jiaotong University, Xi’an 710049;
2. Institute of Water Resources and Hydro-electric Engineering, Xi’an University of Technology, Xi’an 710048)

Abstract: An analytical model for 5-axis flank milling ruled surfaces tolerance is built considering curvature of the baseline. A new concept angle offset is advanced based on studying the relationship between tool axis vector and generatrix, the offset angle evaluate equation is obtained. Radius and angle(R&A) offset algorithm is put forward and applied to calculate tool location data for 5-axis flank milling ruled surfaces to improve the error distribution of the whole milled surface and eliminate the tolerance caused by the different direction of the normal vector, which make sure two baseline of the surface machined precisely. The influences of parameters such as length of generatrix, angle of two normal vectors of generatrix end point to the error distribution are analyzed by an example. The error distribution index of radius offset algorithm and R&A offset algorithm is contrasted, and the result shows that the latter one has higher precision and sounder process technology.

Key words: Ruled surface  Numerical machining  Radius and angle offset algorithm  Error

CLC No: TP391.73

国家高技术研究发展计划资助项目(863计划, 2002AA503020). Received 20070510, received in revised form 20071122

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