In-Line Height Measurement Technique for Directed Energy Deposition Processes

Directed energy deposition (DED) is a family of additive manufacturing technologies. With these processes, metal parts are built layer by layer, introducing dynamics that propagate in time and layer-domains, which implies additional complexity consequently, the resulting part quality hard to predict. Control deposit thickness height critical issue since it impacts on geometrical accuracy, process stability, overall product. Therefore, online feedback control for DED processes with proper sensor strategies required. This work presents novel vision-based triangulation technique through an off-axis located CCD camera synchronized 640 nm wavelength pulsed illumination laser. Image processing machine vision techniques allow in-line measurement right after solidification. The linearity precision proposed setup validated off-and in-process trials laser (LMD) process. Besides, performance developed inspection system has also been tested Arc based compared against experimental weld bead characterization data. In this last case, additionally allowed width contact angles, first runs multilayer buildups.