Dynamic and geometric error assessment of an XYC axis subset on five-axis high-speed machine tools using programmed end point constraint measurements

This paper presents a technique for assessing the volumetric errors on a five-axis machine tool for motion involving two linear axes and one rotary axis at selected feed rates using data from two sources. The first source of data is obtained through a programmed end point constraint procedure with measurement of the 3D volumetric positioning errors between a point on the tool holder and another fixed to the machine table reference frame. The tests involve maintaining the nominal coincidence of these two points whilst exercising the three axes. The second source of data is the position feedback signal from the encoder provided by the machine controller. Tests were carried out at low and high feed rates to evaluate the effect of geometric and dynamic errors. Polynomial functions are used to represent and then predict the geometric errors. The predicted geometric errors are then added to the dynamic errors provided by the servo errors from position feedback signals and propagated to the tool centre point and are compared with the measured volumetric errors. It shows that the influence of the geometric errors are dominant at low feed, whereas the effects of the servo errors of the linear axes become dominant as the feed increases, reaching 80% of the total error at a feed of 10,000 mm/min.

[1]  Wolfgang Knapp,et al.  Model-based ‘Chase-the-Ball’ Calibration of a 5-Axes Machining Center , 2006 .

[2]  J. J. Aguilar,et al.  Development and calibration of self-centring probes for assessing geometrical errors of machines , 2009 .

[3]  John M. Hollerbach,et al.  Self-calibration of single-loop, closed kinematic chains formed by dual or redundant manipulators , 1988, Proceedings of the 27th IEEE Conference on Decision and Control.

[4]  Aun-Neow Poo,et al.  Error compensation in machine tools — a review: Part I: geometric, cutting-force induced and fixture-dependent errors , 2000 .

[5]  J.R.R. Mayer,et al.  Modeling and experimental validation of machine tool motion errors using degree optimized polynomial including motion hysteresis , 2011 .

[6]  Dong-Woo Cho,et al.  Proposition for a Volumetric Error Model Considering Backlash in Machine Tools , 1999 .

[7]  Clément Fortin,et al.  Tool path error prediction of a five-axis machine tool with geometric errors , 2002 .

[8]  J.R.R. Mayer,et al.  Assessment of machine tool trunnion axis motion error, using magnetic double ball bar , 2006 .

[9]  Ralph C. Veale,et al.  Error Compensation of Coordinate Measuring Machines , 1985 .

[10]  H.-T. Yau,et al.  NC simulation with dynamic errors due to high-speed motion , 2004 .

[11]  Masaomi Tsutsumi,et al.  Identification and compensation of systematic deviations particular to 5-axis machining centers , 2003 .

[12]  S. Weikert,et al.  R-Test, a New Device for Accuracy Measurements on Five Axis Machine Tools , 2004 .

[13]  David M. Levine,et al.  Intermediate Statistical Methods and Applications: A Computer Package Approach , 1982 .

[14]  P. G. Ciarlet,et al.  Exercices d'analyse numérique matricielle et d'optimisation , 1982 .

[15]  J. A. Yagüe,et al.  Self-centering probes with parallel kinematics to verify machine-tools , 2006 .

[16]  Raghunath Venugopal.  THERMAL EFFECTS ON THE ACCURACY OF NUMERICALLY CONTROLLED MACHINE TOOLS (NUMERICAL METHODS, EXPERIMENTAL) , 1985 .

[17]  Yoshiaki Kakino,et al.  Diagnosis And Compensation Of Motion Errors In NC Machine ToolsBy Arbitrary Shape Contouring Error Measurement , 1970 .

[18]  J.R.R. Mayer,et al.  Single setup estimation of a five-axis machine tool eight link errors by programmed end point constraint and on the fly measurement with Capball sensor , 2009 .

[19]  W. T. Lei,et al.  Double ballbar test for the rotary axes of five-axis CNC machine tools , 2007 .

[20]  P. G. Ciarlet,et al.  Introduction a l'analyse numerique matricielle et a l'optimisation , 1984 .