Out-of-Plane Geometric Error Prediction for Additive Manufacturing

Additive Manufacturing (AM) is a promising direct manufacturing technology and geometric accuracy of AM built products is crucial to fulfill the promise of AM. The prediction of the out-of-plane or z direction geometric errors has been a daunting task for AM. Although Finite Element Method simulation has been extensively applied to predict 3D deformation and distortion, improving part accuracy purely based on such simulation still needs significant methodology development. We have been establishing an alternative strategy that can be predictive and transparent to specific products and AM processes. Successful results have been accomplished in our previous work to predict the in-plane (x-y plane) geometric errors. In this study we aim to extend the methodology to the out-of-plane geometric error prediction. We provide a novel spatial deviation formulation in which both in-plane and out-of-plane errors are placed under a consistent mathematical framework. The derived predictive model for out-of-plane errors is validated through experimentation using a stereolithography process.