Analysis on simplified engineering model and vibration feature of spherical micromanipulator

A spherical micromanipulator achieves rotations with 3-DOFs of the micro-ball with the relative displacements brought by the frictions between the ruby balls and the micro-ball on the top of piezoelectric tubes. The two-masses simplified engineering model of the stick-slip principle is established under the condition of simplifying spherical higher pair joints. The model of forced vibration and self-excitation oscillation on stick-slip movement is established by dividing the two-masses simplified engineering model and the composite theory of the forced vibration and self-excitation oscillation is presented. The model is demonstrated by simulations. The experiment is also done, and the validity of the model is further proved by the results. At last, the defects of simple driving are discussed, which provides reference to micromanipulator control.