Hinged Adaptive Fiber-Rubber Composites Driven by Shape Memory Alloys—Development and Simulation

Abstract

Adaptive structures based on fiber-rubber composites with integrated Shape Memory Alloys are promising candidates for active deformation tasks in the fields of soft robotics and human-machine interactions. Solid-body hinges improve the deformation behavior of such composite structures. Textile technology enables the user to develop reinforcement fabrics with tailored properties suited for hinged actuation mechanisms. In this work, flat knitting technology is used to create biaxially reinforced, multilayer knitted fabrics with hinge areas and integrated Shape Memory Alloy wires. The hinge areas are achieved by dividing the structures into sections and varying the configuration and number of reinforcement fibers from section to section. The fabrics are then infused with silicone, producing a fiber-rubber composite specimen. An existing simulation model is enhanced to account for the hinges present within the specimen. The active deformation behavior of the resulting structures is then tested experimentally, showing large deformations of the hinged specimens. Finally, the simulation results are compared to the experimental results, showing deformations deviating from the experiments due to the developmental stage of the specimens. Future work will benefit from the findings by improving the deformation behavior of the specimens and enabling further development for first applications.

Investigation and Validation of a Shape Memory Alloy Material Model Using Interactive Fibre Rubber Composites

“…The glass fibres (GFs) used in this work have a fineness of 272 Tex and were assigned to an orthotropic elastic material model with the elastic modulus in the main fibre direction, and the second and third directions were defined for numerical stability. The model parameters used for this work are considered from the previous works in the line of project from Lohse et al [ 41 , 46 ] and are shown in Table 1 and Table 2 .…”

Construction, modeling, and control of a three‐beam prototype using interactive fiber rubber composites

“…One approach to creating soft structures is the integration of textile actuators based on SMAs into fiber-reinforced elastomer composites [9,10]. Fiber-reinforced polymers (FRPs) provide design freedom, allowing tailored combinations of matrix and reinforcement fibers for specific applications.…”

Experimental and Numerical Investigation of 3d Printed Elastomeric Composite With Integrated Sma Actuator

“…Lohse et al [8] developed a novel type of actively deformable composites by knitting SMA Zhenbi Wang, Achyuth R. Annadata, Anja Winkler, Rainer Barth, Anett Endesfelder, Chokri Cherif, Martina Zimmermann, Niels Modler wires into glass fiber fabrics and impregnating them with liquid silicone rubber. By adjusting the knitting pattern, they were able to modify the stiffness of the composite material [13]. Driven by SMA wires, the material structure with flexible middle section and stiff sides can achieve a jointlike motion [13].…”

“…By adjusting the knitting pattern, they were able to modify the stiffness of the composite material [13]. Driven by SMA wires, the material structure with flexible middle section and stiff sides can achieve a jointlike motion [13]. Mersch et al [14] overbraided the SMA wire with copper wires and polyamide yarns, which formed a core-sheath structure, and sewed it onto a glass fiber woven in a U-shaped pattern using a tailored fiber placement (TFP) machine, and finally impregnated the textile with silicone.…”

“…The temperature of the SMA wire can be monitored by the resistance change of the copper wire in the braid tube wrapped around the SMA wire to achieve closed-loop control. In [8,13,14], SMA wires were fully integrated into the matrix material to create a soft intelligent composite. This eliminates the need for subsequent installation of SMA wires and allows for more complex movements by adjusting the configurations of different components within the composite material.…”