Investment micro-casting 3D-printed multi-metamaterial for programmable multimodal biomimetic electronics

Biometric electronics have gained considerable attention in self-sensing, three-dimensional (3D) designs, mechanical drive, and multi-function integration. By leveraging these anisotropic capabilities into devices, metamaterial offers a promising pathway to exciting performance-oriented units. However, such distinctive mismatches in forming processes and inherent material properties are severely restricted in achieving cross-scaled microstructures, causing compatibility issues among well-defined bio-functions and fabrication. Herein, we propose an investment micro-casting 3D printing strategy for custom-molding multi-metamaterials without process barriers. This approach handles the bottlenecks of the hierarchical template replacement in ultra-hydrophobicity microchannels for the free assembly of more than 20 types of challenging-to-form materials. A series of piezoelectric metamaterials are programmed with broadband ranges, imitating nerve distribution that has human-feel touch, bending, and recognition. Our work benefits the stiffness self-perception in dynamic grabbing manipulation, broadening the application of multimodal electronics in bio-embodied robots.