RoboFDM: A Robotic System for Support-Free Fabrication Using FDM

Abstract

This paper presents a robotic system - RoboFDM that can print 3D models without adding support structure, which is considered as the major restriction to the flexibility of 3D printing. The hardware of RoboFDM consists of a robotic arm providing 6-DOF motion to the platform of material accumulation and an extruder forming molten filaments of polylactic acid (PLA). The fabrication of 3D models in this system follows the principle of fused decomposition modeling (FDM). Different from conventional FDM, an input model fabricated by RoboFDM is printed along different directions at different places. A new algorithm is developed to decompose models into support-free parts that can be printed one by one in a collision-free sequence. The support-free printing directions of all parts are determined simultaneously while computing the model decomposition. Experiments have been successfully taken on our RoboFDM system to print general freeform objects in a support-free way.