Development of Ultra high Precision Automatic Assembly System using Piezoelectric Actuators

本研究的目的是利用压电致动器产生的冲击力建立物体在摩擦约束下的定位策略，并利用该策略开发一种超高精度装配系统。主要研究成果如下：(1)研制了一种由压电作动器驱动的脉冲惯性力驱动的运动机构，验证了其在摩擦约束下精确运动物体的能力。(2)研制了一种能够控制三维运动(X、Y和旋转)的定位机构，并进行了定位实验。利用一种新的自适应控制策略和线性规划方法进行了定位实验。研制了一种超高精度机床主轴上的工件定位装置，并对其性能进行了验证。结果表明，利用压电致动器产生的冲击力实现超高精度的对准是非常有效的。由于这些实验是在接近工业装配操作的实际条件下进行的，因此这些结果有望应用于工业装配操作。

The aim of this research is to establish positioning strategy of an object under frictional constrain utilizing impulive force generated by piezoelectric actuators and to develop a ultrahigh precise assembly system using it. The research results can be summed up as follows :(1) A motion mechanism driven by impulsive inertial force by piezoelectric actuator is developed and its ability to move a object precisely under frictional constrain is verifed.(2) A positioning mechanism which is capable of controlling three dimensional motion (X,Y,and Rotation) is developed and positioning experiments are carried out. Positioning experiments are carred out utilizing a newly proposed control strategy with adaptive control and linear programming method. It was possible to align a workpiece at the minimum resolution of the positioning sensor.(3) A workpiece positioning device for positioninig workpiece on the main spindle of a ultrahig precision machine tool is developed and its performance is verified. It was possible to align a workpiece at the resolution below 500 nanometer.Those results show that a positioning system of a workpiece using impulsive force generated by piezoelectric actuator is quite effective in workpiece alignment at ultrahigh precision level. Since, those experiments are carried out in close condition to the actual assembly operation in industries, it is expected that those results will be applied to industrial assembly operations.