Variable feedrate interpolation of NURBS Toolpath

Authors: Yuwen Sun Jianfeng Zhou Dongming Guo

Publish Date: 2013/10/13

Volume: 26, Issue: 5, Pages: 757-776

PDF Link

Abstract

Variable feedrate interpolation algorithms for fiveaxis parametric toolpath are very promising but still rather limited currently In this paper an offline feedrate scheduling method of dual NURBS curve is presented with geometric and kinematical constraints For a given dual parametric curve the feedrates of sampling points are first scheduled sequent with confined feedrate of cutter tip and machine pivot chord error normal acceleration and angular feedrate Then the feedrate profiles of angular feed acceleration sensitive regions of the path are adjusted using a bidirectional scanning algorithm After that a linear programming method is used to adjust the feedrate profiles of linear feed acceleration sensitive regions and control the linear feed acceleration of both cutter tip and machine pivot within preset values Further a NURBS curve is used to fit the feedrates of sampling points Finally illustrative examples are carried out to validate the feasibility of the proposed feedrate scheduling method The results show that the proposed method has the ability of effectively controlling the angular feed characters of cutter axis as well as the chord error and linear feed characters of cutter tip and machine pivot and it has potential to be used in high accuracy and high quality fiveaxis machining

Keywords: