Predictive modeling of in-plane geometric deviation for 3D printed freeform products

Although 3D printing or additive manufacturing (AM) holds great promise as a direct manufacturing technology, the dimensional geometric accuracy remains a critical issue, especially for freeform products with complex geometric shapes. Efforts have long been attempted to improve the accuracy of AM built freeform products. But there is a lack of generic methodology transparent to specific AM processes. This study fills the gap by establishing a general model predicting the in-plane (x-y plane) geometric deviations of AM built freeform products. Built upon our previous predictive model and optimal compensation study for cylinder and polyhedron shapes, this work makes a breakthrough by directly predicting arbitrary freeform shape deviations from CAD design. Experimental investigation using stereolithography process successfully validates the proposed methodology, which indicates the prospect of optimal compensation for freeform products built by a varieties of AM processes.