建立了考虑刀杆柔性的球头铣刀铣削振动模型，探讨了交变轴向力对刀杆固有频率的影响。考虑刀具动态变形和工件表面波纹对切削厚度的再生反馈，建立了球头刀铣削动力学模型，对铣削中的动态铣削力和刀杆振动进行了仿真，证明了离线仿真可以对铣削过程动特性做出预测。

为提高铣削加工的安全性和生产效率，有必要在加工实际进行之前准确地预测切削过程的物理信息，如铣削力、刀具振动等。给出了球头铣刀刃线几何模型，采用理论切削力分析与实验—系数识别相结合的方法建立了新的螺旋刃球头铣刀的铣削力模型。对不同切削条件下的铣削力进行了仿真，与实验测量数据吻合良好，证明离线仿真可以对铣削力做出较准确的预测。

In order to implement active control during surface grinding, a workpiece micro-positioning table utilizing a piezoelectric translator has been developed. The workpiece table has a working area of 100´100 mm and a nominal working range of 45 mm. The resolution of the workpiece table is less than 20 nm and the natural frequency is 579.2 Hz. The rigidity of the workpiece table under the open loop condition is approximately 17 N/mm. Under the closed loop condition, the rigidity is better than 400 N/mm. The design of the workpiece table is presented together with considerations to achieve the high dynamic characteristics, where the maximum acceleration is up to 33g (g is the acceleration of gravity). The dynamic models of the piezoelectric translator and the workpiece table have been established. Experimental testing has been carried out, verifying the performance of the workpiece table and the established dynamic models for the workpiece micro-positioning table. Ó 2001 Elsevier Science Ltd. All rights reserved.

A micro-positioning table for precision machining applications is developed utilizing a piezoelectric translator to generate high speed precision motions with accelerations up to 33.51 g. The piezoelectric translator is preloaded by four springs such that the moving part in the table keeps contact with the translator. The contact between the translator and the moving part is of the hertz contact type. It is a typical design for high performance micro-positioning devices. It is found that the hertz contact may not be maintained and detachment occurs when implementing large step motions. The detachment phenomenon is analyzed and the models to determine the separation time and the maximum overshoot are established. It is found that the stiffness of the preloading springs and the distance of compression for preloading are the key parameters of the detachment. A pseudo-step command signal design is proposed to use as a solution in order to conveniently reduce the overshoot without compromising the settling time. Experimental tests have been carried out, verifying the established models for the micro-positioning device.