Abstract: In order to understand the trajectory of the screen in space clearly, according to the rigid body dynamics theory, the trajectory equation of the mesh in space was deduced. With the help of virtual prototyping technique and the virtual prototyping technology, the trajectories of the points on mesh were simulated. When the exciting forces do not pass through the body’s centroid and are placed on both sides of the body, the movement of arbitrary point on the mesh is the synthetic motion combined with translation along coordinate axis and the rotation around this axis. Through adjusting the relative position between polarized block and the centroid of the vibrating screen, the arbitrary point on mesh was moved like an ellipse with ellipticities unequal to each other, and the amplitude of screen at the entrance reached 2mm, which is conducive to material stratification.