AM optimization framework for part and process attributes through geometric analysis

In additive manufacturing (AM) processes, part and process attributes are often optimized with build orientation/tool-path direction. Both of them may alter the layer topology and tool-path pattern which implicitly affect the part and process attributes. However, optimizing either build orientation or tool-path direction independently undermines the hierarchical relationship in the AM process plan and may produce a sub-optimal solution. In this paper, an integrated framework is proposed to quantify their combined effect on the part and process attributes by analyzing the generated geometry. The proposed methodology is designed on the basis of the layer geometries to ensure manufacturability and minimize fabrication complexity in AM processes. The objective function is formulated with weighted attributes and the weights are optimized by Hypothetical Equivalents and Inequivalents Method (HEIM). Both build orientation and tool-path/deposition direction are concurrently optimized using a Genetic Algorithm (GA). The proposed algorithm is implemented on two free form shaped objects and the process converges within a reasonable number of iterations. The outcome is also compared with an exhaustive search method. (C) 2016 Elsevier B.V. All rights reserved.