Open AccessResearch on Error Modeling and Identification Technology of CNC Camshaft Grinder
Author(s) -
Haohao Tao,
Jinwei Fan,
Xiaojun Jia,
Jianhua Yin,
Guochao Qi
Publication year - 2019
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/612/3/032120
Subject(s) - camshaft , machining , machine tool , kinematics , coordinate system , grinding , transformation matrix , rigid body , computer science , control theory (sociology) , homogeneous coordinates , multibody system , numerical control , constraint (computer aided design) , trajectory , control engineering , algorithm , mechanical engineering , engineering , mathematics , computer vision , geometry , artificial intelligence , physics , control (management) , classical mechanics , quantum mechanics , astronomy
Taking certain type of CNC camshaft grinders as the research object, through the analysis of its structure and movement to determine a total of 21 error parameters, a model describing the motion relations between adjacent body coordinate systems containing the error parameters was established. The machine movements were classified into two kinematic chains: the “bed-workpiece” and “bed-tool”. The topological structure of the machine tool was built and then the multi-body system theory was applied to model the errors of the machine tool. Body coordinate systems and motion reference coordinate systems were set up on each moving body and the corresponding transformation matrix was derived by joining the motion relation models between adjacent body coordinate systems. In order to achieve precision machining in the case of the existence of influential errors, a constraint equation Pw = Pt was put forward and solved. A mathematical model of the X-C axis linkage during camshaft grinding was proposed to work out the grinding point coordinates in the workpiece coordinate system and tool coordinate system. Three kinds of measurement methods were provided to identify 15 error parameters affecting the camshaft machining by using a cue instrument, which provides necessary conditions to research the machine tool error compensation.