• Ertveldt, Julien
• Guillaume, Patrick
• Sanchez Medina, Jorge
• Hinderdael, Michaël

Abstract

<p>Real-time control of melt pool temperature, deposition width, and height has shown to deliver significant improvements in both material properties and part geometry during the laser based directed energy deposition process. For accurate controller design a mathematical model of the complex DED process is required. In this paper an experimental frequency-domain system identification approach to autonomously obtain a transfer-function model with multi-spectral camera-based melt pool intensity and temperature as input, and laser power as output, are considered in a linear framework. A Maximum-Likelihood frequency domain approach in the stochastic output-error framework is used. It was concluded that both intensity and temperature can be used to model the dynamics of the melt pool, with very little difference between both. Validation of the model on a sine excitation showed general good agreement but also the presence of nonlinear distortions due to the influence of the chosen toolpath.</p>

Topics

• Deposition
• impedance spectroscopy
• melt
• directed energy deposition