Electrothermally controlled origami fabricated by 4D printing of continuous fiber-reinforced composites

Active origami capable of precise deployment control, enabling on-demand modulation of its properties, is highly desirable in multi-scenario and multi-task applications. While 4D printing with shape memory composites holds great promise to realize such active origami, it still faces challenges such as low load-bearing capacity and limited transformable states.

Recently, researchers from the Computational design and fabrication group (CodeFab) at the Southern University of Science and Technology (SUSTech) reported a fabrication-design-actuation method of continuous fiber-reinforced composites for creating precisely controlled electrothermal origami with excellent mechanical performance and spatiotemporal controllability. The electrothermal origami can be reconfigured to arbitrary configurations by manipulating activation parameters.

The joint research team, led by Prof. Yi XIONG and Prof. Qi GE at SUSTech, has published their research findings in Nature Communications. The article is entitled “Electrothermally controlled origami fabricated by 4D printing of continuous fiber-reinforced composites”.

4D printing of electrothermal origami

The electrothermal origami is fabricated by an FDM-based (Fused Deposition Modelling) 3D printer designed for continuous carbon fiber-reinforced shape memory polymer composites. The process involves melting shape memory polymer and impregnating it into fibers, followed by coextrusion on the printing platform to create patterns of each layer according to the predetermined printing path. A single continuous carbon fiber-reinforced shape memory polymer composite bead is deposited on the inner surface of the hinge to provide localized Joule heating, thereby triggering shape-shifting. Moreover, fibers also play other roles, fibers in the stiff panels are used for reinforcement and in the hinges for reinforcement and heat conduction.

4D printing of continuous fiber-reinforced shape memory polymer electrothermal origami composite. Credit: Southern University of Science and Technology

Precise control of the electrothermal origami

The research investigates the impact of continuous carbon fiber's electrical time on the shape-shifting behavior of the electrothermal origami and establishes a multi-physics simulation model that considers electrical, thermal, and mechanical effects for its deployment control process. The electrothermal origami can be locked in an intermediate state during the free recovery process by controlling the duration of the electrical current input. This phenomenon is facilitated by the unique attributes of continuous carbon fibers, which can rapidly reach high temperatures upon activation and cool down quickly upon deactivation. The research also exhibits the spatiotemporal controllability (localized control, unfolding angle control, and sequence control) of precisely controlled electrothermal origami using airplane-shaped origami as an example. The airplane-shaped origami can be deployed in a complex stepwise routine. This approach allows for selective and localized Joule heating to trigger the precise deployment of specific hinges at different times without coupling with others.

FEA and experimental shape-shifting behavior of airplane-shaped electrothermal origami structure. Credit: Southern University of Science and Technology

Reconfigurability of the precisely controlled electrothermal origami

This precisely controlled electrothermal origami has reconfigurability. By applying diverse electrical inputs guided by the multi-physical simulation, the precisely controlled electrothermal origami strip structure can be deployed into multiple configurations, including single-floor, double-floor, and metamaterials unit configurations. Additionally, control of the actuation sequence for the precisely controlled electrothermal origami strip structure can provide additional functionalities, i.e., grasping, which is also demonstrated in this work.

Reconfigurable precisely controlled electrothermal origami. Credit: Southern University of Science and Technology

Multifunctional electrothermal Miura-origami based on precise control

The research also demonstrates a few potential applications taking advantage of the capabilities of on-demand modulation for properties, i.e., geometrical and mechanical properties, of this precisely controlled electrothermal origami. A Miura-origami unit is designed and printed, whose mechanical properties can be tuned by manipulating activation parameters. Its stiffness and strength can be varied by an order of magnitude, forming a large performance space. By combining the deployable Miura-origami units with different geometry designs, a variable thickness wing with reconfigurable geometry and inversely designable airfoil for multiple flight scenarios can be realized. Moreover, these precisely controlled electrothermal Miura-origami units also can be digitally arrayed to form combinatory digital architected material. The combinatory digital architected material can effectively decouple the deformation constraints between interconnected building blocks and greatly increase the deformability and programmability of materials. Its mechanical performance can be modulated by simultaneously considering geometric design and deployment control.

Reference: “Electrothermally controlled origami fabricated by 4D printing of continuous fiber-reinforced composites” by Yaohui Wang, Haitao Ye, Jian He, Qi Ge, Yi Xiong., 14 March 2024, Nature communications.

DOI: https://doi.org/10.1038/s41467-024-46591-3