A vibrating metal strip, driven by piezoelectric ceramics, can rotate a cluster of small particles around a fixed node. Under appropriate driving conditions, the rotation becomes stable and the rotational radius of the cluster of small particles can reach the edge of the structure. This paper is focused on the analyses on the mechanisms of this phenomenon by Finite Element Method. First, the Finite Element Analysis code ANSYS was used to simplify the experimental structure and a preliminary analysis was performed. Then, based on the preliminary analysis, the structure of the metal strip was modified and reanalyzed. The finite element analytical results showed that the driving mechanism of the rotation of a cluster of particles is the traveling waves around nodes which were caused by non-uniform vibrations at the root of wedged plate structure, and the number of valid nodes is closely related to the width of the wedged plate.