Mechanical model and contouring analysis of high-speed ball-screw drive systems with compliance effect

The compliance effect of a high-speed ball-screw feed-drive system is modelled in this work. A mechanical model of a ball-screw feed drive system including the motor, ball-screw, coupling, supporting bearing, linear guide and machine structure was developed. It was found that at high acceleration, the mechanical compliance caused a significant contouring error. Smoothing the acceleration and deceleration control input command did improve the transient deviation in the contouring error. However, the steady state error caused by the elastic elongation in the mechanical elements was not improved. It was also shown that the inertia force of the slide and saddle comprised the dominant loading on a high speed machine tool drive mechanism. A topology structure optimisation method is proposed to reduce the moving weight. This method can help the designer efficiently reduce the moving weight of a machine tool axis in a systematic way. More than a 30% weight reduction was demonstrated in a spindle carrier structural design.

[1]  Ming-Jen Kuo,et al.  NURBS machining and feed rate adjustment for high-speed cutting of complex sculptured surfaces , 2001 .

[2]  Yoram Koren,et al.  Advanced Controllers for Feed Drives , 1992 .

[3]  Yusuf Altintas,et al.  High speed CNC system design. Part III: high speed tracking and contouring control of feed drives , 2001 .

[4]  Frank J. Bartos.  Electric servos do more with less , 1997 .

[5]  Hsi-Yung Feng,et al.  Integrated tool path and feed rate optimization for the finishing machining of 3D plane surfaces , 2000 .

[6]  I. Ali,et al.  Advanced Interpolation Techniques for N.C. Machines , 1993 .

[7]  Manfred Weck,et al.  Sharp Corner Tracking Using the IKF Control Strategy , 1990 .

[8]  Atsushi Matsubara,et al.  High Speed and High Acceleration Feed Drive System for NC Machine Tools , 1996 .

[9]  Jiri Tlusty,et al.  Effect of low-friction guideways and lead-screw flexibility on dynamics of high-speed machines , 1995 .

[10]  Mizuho Ninomiya,et al.  Analysis of linear guide and ball screw stiffness , 1999 .

[11]  Wei-Yao Hsu,et al.  Design and analysis of a tripod machine tool with an integrated Cartesian guiding and metrology mechanism , 2004 .

[12]  T. Tsujisawa,et al.  High-accuracy path-tracking by multi-axis coordination in CNC machines , 1994, Proceedings of IECON'94 - 20th Annual Conference of IEEE Industrial Electronics.

[13]  Masayoshi Tomizuka,et al.  High-speed end milling using a feedforward control architecture , 1996 .

[14]  An-Chen Lee,et al.  New direct velocity and acceleration feedforward tracking control in a retrofitted milling machine , 1999 .