Design of ultrasonic standing wave levitation support for three-dimensional printed filaments

Fused deposition modeling (FDM) three-dimensional (3D) printing is the process of forming a part by depositing molten thermoplastic materials layer by layer. Support structures need to be added below the overhangs or bridges in 3D printing. This paper proposes an idea for support-free FDM printing by studying the method of filament levitation. In this paper, an ultrasonic phased array device is designed, and different slender objects with length much longer than the sound wavelength are levitated in the air by multiple standing wave points. Experiments show that slender objects can be stably held at the sound pressure nodes in the standing wave field. After adding the ultrasonic field in FDM printing, the maximum deformation of single filament due to gravity on the bridge structure decreases from 5 to 2 mm. This proves that it is feasible for an ultrasonic phased array system to play an important role in the field of support-free FDM printing.