Abstract: Estimation algorithms, methods, and systems are provided that estimate the internal temperatures inside of a part being built using powder bed fusion (PBF). Closed-loop state estimation is applied to the problem of monitoring temperature fields within parts during the PBF build process. A simplified linear time-invariant (LTI) model of PBF thermal physics with the properties of stability, controllability and observability is presented. In some aspects, Model Predictive Control (MPC) may be used as an expanded application of an Ensemble Kalman Filter (EnKF) methods to control the PBF process. MPC is used to forecast the PBF build process behavior N time steps into the future and identifies inputs that drive the temperature of a corresponding node in a mesh of n nodes towards a predetermined target temperature.

Abstract: Estimation algorithms, methods, and systems are provided that estimate the internal temperatures inside of a part being built using a Finite Element Method (FEM)-based thermal model of Powder Bed Fusion (PBF) heat transfer. Closed-loop state estimation is applied to the problem of monitoring temperature fields within parts during the PBF build process. The PBF laser is very small, therefore, so too are the FEM elements nearby the laser. Thus, as the PBF laser moves, a region of high mesh density moves along with it as it progresses over a geometry. In an aspect, regions of high mesh density are predetermined for each time step according to a predefined schedule of laser movements.

Abstract: Estimation algorithms, methods, and systems are provided that estimate the internal temperatures inside of a part being built using powder bed fusion (PBF). Closed-loop state estimation is applied to the problem of monitoring temperature fields within parts during the PBF build process. A simplified linear time-invariant (LTI) model of PBF thermal physics with the properties of stability, controllability and observability is presented. In some aspects, an Ensemble Kalman Filter is applied to the model. Linear time-varying (LTV) systems are also contemplated.

Abstract: Estimation algorithms, methods, and systems are provided that estimate the internal temperatures inside of a part being built using powder bed fusion (PBF). Closed-loop state estimation is applied to the problem of monitoring temperature fields within parts during the PBF build process. A simplified linear time-invariant (LTI) model of PBF thermal physics with the properties of stability, controllability and observability is presented. In some aspects, an Ensemble Kalman Filter is applied to the model. Linear time-varying (LTV) systems are also contemplated.