Abstract

Near-field acoustic levitation (NFAL) is an innovative contactless handling technology with extensive potential in precision manufacturing and microelectromechanical systems. Despite its promise, challenges persist in addressing low levitation force and inevitable vibration issues in noncontact positioning and handling processes. This study introduces methods to enhance levitation force and reduce vibrations in NFAL systems through multiple regions of air-film compensation, specifically compensating the annular- and central-regions, respectively. Soft materials are strategically placed in the levitation plate's circular and annular grooves to avoid altering the radiator's resonant frequency. The governing equations of the squeeze film are formulated to analyze the levitation force and vibration amplitude. Numerical simulations and experimental validations demonstrate that annular-region compensation uses soft materials to create "seal ring" and "wedge shape" effects, enhancing the air-film pressure and average levitation force. Central-region compensation employs soft materials to minimize pressure differences and gradients of levitation force within the solution domain. These results confirm that NFAL systems via air-film compensation can effectively enhance different performances, providing a viable solution to current limitations.