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arXiv · 2611.07704

Towards Track Height Control in Additive Manufacturing on Porous Substrates: An Approach for System Identification and Controller Selection

Abstract

Additive manufacturing is transforming the creation of materials and parts, enabling the design and manufacturing of multifunctional parts with tailored properties. One compelling example is the combination of a porous core and a non-porous surface, which offers significant advantages in terms of weight reduction, material efficiency, strength and wear resistance. Directed Energy Deposition (DED) processes enable the transition from porous core to non-porous part surface by closing the pores. However, the surface-layer of porous substrates presents a substantial challenge to achieving consistent track heights during DED, directly impacting the final part geometry and performance. Therefore, precise control of the deposition process is crucial for realising the full potential of the multifunctional parts. In order to address this challenge, this work presents a conceptual approach for track height control during Laser-based Directed Energy Deposition (DED-LB) on porous substrates. First, the DED-LB process and the associated measurement setup are explained, along with a discussion of their limitations. The focus then shifts to the control problem, beginning with system identification to characterise the process dynamics. Subsequently, a selection of control strategies is investigated, as well as their compatibility with the process. This research provides a foundational step toward reliable additive manufacturing on porous substrates, and thus toward producing multifunctional parts.

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Amelie Schatull, Torge Kolditz, Simon Kleinschmidt, Annika Raatz, Jörg Seewig. 2026-11-05. Towards Track Height Control in Additive Manufacturing on Porous Substrates: An Approach for System Identification and Controller Selection. https://arxiv.org/abs/2611.07704

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