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.

中文翻译：

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三维印花长丝超声驻波悬浮载体的设计

熔融沉积建模（FDM）三维（3D）打印是通过逐层沉积熔融的热塑性材料来形成零件的过程。需要在3D打印中的悬垂或桥下添加支撑结构。通过研究灯丝悬浮法，提出了一种无支撑的FDM印刷的思想。本文设计了一种超声相控阵装置，通过多个驻波点将不同长度比声波长长得多的细长物体悬浮在空中。实验表明，纤细的物体可以稳定地保持在驻波场的声压节点处。在FDM打印中添加超声场后，由于桥结构上的重力而导致的单丝最大变形从5毫米减小到2毫米。