  With the rapid development of powder-based additive manufacturing,
depowdering, a process of removing unfused powder that covers 3D-printed parts,
has become a major bottleneck to further improve its productiveness.
Traditional manual depowdering is extremely time-consuming and costly, and some
prior automated systems either require pre-depowdering or lack adaptability to
different 3D-printed parts. To solve these problems, we introduce a robotic
system that automatically removes unfused powder from the surface of 3D-printed
parts. The key component is a visual perception system, which consists of a
pose-tracking module that tracks the 6D pose of powder-occluded parts in
real-time, and a progress estimation module that estimates the depowdering
completion percentage. The tracking module can be run efficiently on a laptop
CPU at up to 60 FPS. Experiments show that our depowdering system can remove
unfused powder from the surface of various 3D-printed parts without causing any
damage. To the best of our knowledge, this is one of the first vision-based
robotic depowdering systems that adapt to parts with various shapes without the
need for pre-depowdering.
