An Evolutional Algorithm for Automatic 2D Layer Segmentation in Laser-aided Additive Manufacturing

TL;DR

This paper introduces an autonomous evolutionary algorithm for automatic 2D layer segmentation in laser-aided additive manufacturing, significantly improving efficiency and solution diversity for complex geometry toolpath planning.

Contribution

It presents the first automatic segmentation method for LAAM layers using an evolutional computation approach, enhancing efficiency and solution variety.

Findings

Validated effectiveness through case studies

Roughing-finishing strategy improves performance

Multi-processing increases solution diversity

Abstract

Toolpath planning is an important task in laser aided additive manufacturing (LAAM) and other direct energy deposition (DED) processes. The deposition toolpaths for complex geometries with slender structures can be further optimized by partitioning the sliced 2D layers into sub-regions, and enable the design of appropriate infill toolpaths for different sub-regions. However, reported approaches for 2D layer segmentation generally require manual operations that are tedious and time-consuming. To increase segmentation efficiency, this paper proposes an autonomous approach based on evolutional computation for 2D layer segmentation. The algorithm works in an identify-and-segment manner. Specifically, the largest quasi-quadrilateral is identified and segmented from the target layer iteratively. Results from case studies have validated the effectiveness and efficacy of the developed algorithm. To further improve its performance, a roughing-finishing strategy is proposed. Via multi-processing, the strategy can remarkably increase the solution variety without affecting solution quality and search time, thus providing great application potential in LAAM toolpath planning. To the best of the authors knowledge, this work is the first to address automatic 2D layer segmentation problem in LAAM process. Therefore, it may be a valuable supplement to the state of the art in this area.