Design and Simulation of Multi-Tiered 4D Printed Objects

Abstract:
4D printing refers to the 3D printing of models which deform over time in response to some stimulus. This process can be used to create objects with heavily curved geometries by first printing them flat, then subsequently warping them to a desired final shape. Most work in 4D printing involves flat, single-layer, effectively two dimensional initial printed configurations, which limits the print's ability to warp and curve in both directions. As a step to address these limitations, we propose a novel modeling and simulation framework for 4D printed, multi-tiered grids. These grids consist of multi-layered, interconnected nodes that differentially shrink at each layer in order to create curvatures in either direction. These nodes can all be assigned curvature and size values independently, giving grids the ability to create complex surfaces. Bezier patches and triangle mesh models can be used as targets to generate grids that closely mimic the geometry of the input surface after stimulation. Under forward simulation, nodes within grids are able to recreate distances and curvatures measured on target surfaces within approximately 1% tolerance, and full grids closely resemble their desired shapes.