| The high speed machining (HSM) requires that the feed drives of CNC machine tools have high speed and high acceleration. In such operation condition, the dynamic characteristic of the drive framework will have an important influence on machining quality and efficiency and challenge current control methods in machine tool. Therefore, the dynamic behavior of the drive framework should be researched deeply and considered in the servo control and the CNC motion command. A new feed drive, Drive at Center of Gravity (DCG), is researched as an object, including its dynamic behavior and high precision motion control strategy. The main contributions of this dissertation are shown as follows:The perfect DCG could eliminate the turnover vibration and distortion to get a smooth movement, which is proved theoretically by building the dynamic model of DCG in this thesis. The effect of changeable design parameters on the dynamic performance of DCG is analyzed by building parameter model. The results provide important design principles for DCG. A whole dynamic simulation platform of high speed feed drive is built based on UG and ADAMS. The validity of simulation model is validated using experimental mode analysis. The motion simulation results comparing a DCG with a traditional feed drive indicate that DCG has an outstanding advantage to restrain the vibration in a high acceleration. Especially in the corner of the contour, the DCG acquires preponderant precision. The experiments in the DCG platform validate the characteristic.A numerical analysis to the torsion vibration of time-varying rotor-screw feed drive system on the basis of finite element method is presented to get an insight for the effect of in-time moving position of the table and changeable work-piece mass on the free vibration characteristic of the system. The results obtained demonstrate that the natural frequencies are notably changed with the position change of the table movement.Considering the torsion dynamic of rotor-screw system, the mathematic model of servo drive system that utilizes IIR notch filter to compensate the torsion vibration of first two orders is built. Moreover, the effects of changing torsion modes on notch filter are analyzed. In order to adapt the changing modes, adaptive notch filters that are based on gain scheduling and neural net respectively are presented. Example analysis validates the two adaptive notch filters. Combining the geometrical and kinematic constraint conditions of NURBS interpolation and little line interpolation with the physical constraint conditions that are based on the dynamic characteristic of machine tool feed drive, the mixed constraint conditions are built for the motion command. Look-ahead control and autonomic scheduling are realized according to the mixed constraint conditions during the interpolaton process. The presented interpolation algorithms that are applied in the HNC-22MF CNC system are validated experimentally. The results indicate that the algorithms are viable.A mechatronic integrated simulation model for a CNC feed drive that takes example by DCG platform is building. Based on an improved evaluation method of dynamic performance for feed drives proposaled by this thesis, a two-stage tuning method of servo parameter is presented. A case study shows that this method simplifies the test process effectively in the experimental platform. Moreover, the dynamic performances comparing a DCG with a traditional feed drive are simulated. The results indicate that DCG can realize higher position loop gain and higher velocity loop gain, namely has a higher servo control bandwidth.
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