Programming material compliance and actuation: hybrid additive fabrication of biocomposite structures for large-scale self-shaping

Abstract

We present a hybrid approach to manufacturing a new class of large-scale self-shaping structures through a method of additive fabrication combining fused granular fabrication (FGF) and integrated hygroscopic wood actuators (HWAs). Wood materials naturally change shape with high forces in response to moisture stimuli. The strength and simplicity of this actuation make the material suitable for self-shaping architectural-scale components. However, the anisotropic composition of wood, which enables this inherent behavior, cannot be fully customized within existing stock. On the other hand, FGF allows for the design of large physical parts with multi-functional interior substructures as inspired by many biological materials. We propose to encode passively actuated movement into physical structures by integrating HWAs within 3D-printed meta-structures with functionally graded stiffnesses. By leveraging robotic manufacturing platforms, self-shaping biocomposite material systems can be upscaled with variable resolutions and at high volumes, resulting in large-scale structures capable of transforming from flat to curved simply through changes in relative humidity.

Cross-Sectional 4D-Printing: Upscaling Self-Shaping Structures with Differentiated Material Properties Inspired by the Large-Flowered Butterwort (Pinguicula grandiflora)

“…Cross-sectional structures could also be integrated with conventional bilayers, which enables the design of structures with programmed shape deformations in the XY, XZ, and YZ planes. Furthermore, the applications of 4D-printing can be expanded on a large scale [ 50 ] by combining cross-sectional structures with other structural and hygroscopic material systems, such as hygroscopic wood elements. Upscaling 4D-printed structures requires further considerations in terms of their structural integrity.…”

Review of advanced techniques for manufacturing biocomposites: non-destructive evaluation and artificial intelligence-assisted modeling

“…Also, Coriolis Composites [174] has developed CAD Fibre and CAT Fibre, which consist of programming, simulation and post-processing modules of AFP. AFP simulation with CAD Fibre software works based on CATIA version 5, it can be used for designing molds and then importing the mold files into the simulation interface [175]. In addition to these, FiberGrafiX was developed by Entech [176] to perform AFP simulation in studying the various process parameters.…”

A perspective on plant robotics: from bioinspiration to hybrid systems

“…To implement nastic movements, which are still observable in fossil scales of pine cone [34,54], hygroscopic materials [55] and hydrogels are used in engineering [56][57][58]. Correa et al [34,59,60] and Cheng et al [37,[61][62][63] use moisture-responsive swelling materials in their systems to demonstrate adaptive shading and self-erecting structures. Plant and especially root growth has inspired various growing robots, which use material deposition (as in 3D printing) [8,[64][65][66] or pneumatic expanding systems to move, grow, burrow, and navigate [9,17,26,67].…”