Adaptive Rastering Algorithm for Freeform Extrusion Fabrication Processes


An adaptive rastering algorithm has been developed to reduce the 'horizontal' staircase error and/or fabrication time for freeform extrusion fabrication processes of 3D 'solid' parts. It analyses the geometry of each layer and changes the width of each line of the raster adaptively in order to reduce the staircase error and/or increase productivity. For each line, the maximum width that results in a staircase error smaller than a predefined threshold is determined for decreasing the fabrication time, increasing the dimensional accuracy, or both. To examine the efficacy of the proposed technique, examples are provided in which staircase errors and fabrication times are compared between uniform and adaptive rastering methods for each part. The results show a considerable improvement in accuracy and/or fabrication time for all parts studied when using the adaptive rastering algorithm.


Mechanical and Aerospace Engineering


This work was supported by the National Energy Technology Laboratory of the U. S. Department of Energy's Office of Fossil Energy [DE-FE0012272]; the Intelligent Systems Center at the Missouri University of Science and Technology.

Keywords and Phrases

Algorithms; Errors; Extrusion; Fabrication; Adaptive slicing; Dimensional accuracy; Fabrication process; Fabrication time; Freeforms; Geometrical error; Rastering; Staircase effect; Stairs; Adaptive rastering; Extrusion-based additive manufacturing

International Standard Serial Number (ISSN)

1745-2759; 1745-2767

Document Type

Article - Journal

Document Version


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© 2015 Taylor & Francis, All rights reserved.

Publication Date

01 Oct 2015