Design for 4D printing: A voxel-based modeling and simulation of smart materials

In the wake of the breakthrough being by additive manufacturing (AM), there is another rapidly growing manufacturing progress: 4D printing (4DP). It is basically AM with, inter alia, smart materials (SMs). Owing to the stimulus-responsive behaviors of these materials, the parts so manufactured are imbued with the ability to change. 4DP is being given huge research efforts regarding its manufacturing aspects. However so little is made to let designers explore the so uncovered design space. Compared to DFAM, what could be called Design for 4D printing (DF4DP) does lag far behind. In this artide, a modeling framework for simulating SMs and conventional materials behaviors on a voxel basis is proposed: this allows for arranging materials in any distribution and rapidly evaluating the behavior of the distribution. Homogeneous and heterogeneous objects made of conventional materials and SMs were modeled and simulated. The modeled SMs were limited to non-programmable shape changing SMs including: piezoelectric material, electro-/magneto-/photostrictive materials and hydrogel. A printed smart valve and a theoretical actuator (both from other publications) were used as test cases. These simulations have a speed reasonable for the design iterations needed in conceptual design phase and they yield results in good agreement with physics. (C) 2019 The Authors. Published by Elsevier Ltd.