SUBJECT: M.S. Thesis Presentation
BY: Michael Carrillo
TIME: Tuesday, May 10, 2022, 9:00 a.m.
PLACE: MRDC Building, 4211
TITLE: Monitoring Laser Powder Bed Fusion Recoater Blade Vibrations for Collision Avoidance
COMMITTEE: Dr. Christopher Saldana, Co-Chair (ME)
Dr. Katherine Fu, Co-Chair (ME)
Dr. Thomas Kurfess (ME)


Laser powder bed fusion (LPBF) relies on the precise spreading of powder by the recoating blade to build the next layer of material. One of the issues during fabrication is the thermal warping of parts which can collide with the recoating blade and cause print failure. As parts gradually thermally warp, the distance from the recoater blade to the parts decreases. Most LPBF machines have safety mechanisms in place to detect high current in the driver motor of the recoater blade when part is obstructing the recoat path. This safety mechanism, however, detects when the blade has already collided with the thermally warped part which damages both the part and the recoater blade. Previous research has shown the ability to detect vibrations on the recoating arm due to parts thermally warping and approaching the recoater blade. The distance from the parting being printed and the recoater blade is not known in previous research. This thesis aims at mapping how far parts must be to cause vibrations. By linking the distance from the part to the recoater blade to the vibrations, an early detection system can have more confidence in preventing a crash. Earlier detection of a collision helps the user make an informed decision to mitigate damage and loss of productivity.