Development of promising acoustic levitation technique by alternating acoustic focal spots rapidly

Among many non-contact particle manipulation methods, acoustic levitation (AL) is most popular since it is not restricted by the characteristics of the target material. However, existing AL's structures still have some disadvantages which limited their potential further applications. Take the application of acoustic twin tweezer for example, complex calculations make them difficult to be commercialized. Therefore, in this paper, an innovative method is proposed to implement the AL more intuitively and freely. Through switching two adjacent focal points rapidly, it is possible to generate an acoustic trap with low-density sound field on specific position. The object would be hold in this trap and could be moved by changing the position of the trap. In this paper, serval acoustic levitating experiments have been conducted to verify the proposed method. Besides, acoustic field simulation was also performed to visualize and quantify the presence of acoustic trap. The experimental results including levitating one object, two object, and transportation of a single target have proved the levitating capability of the proposed method. Moreover, the results of simulation also proved that the proposed approach could successfully create acoustic traps.