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Inspired by the mineralization process of bone, we have investigated mineralization on piezoelectric samples immersed in a solution with mineral ions. We have utilized polyvinylidene fluoride as a piezoelectric material and 10× simulated body fluid as a mineral solution. Three synthetic material systems were developed and characterized using scanning electron microscopy, X-ray diffraction, nanoindentation, and scratch testing. With these techniques, we provide insights into how the characteristics of the mineralization protocol affect the microstructure, chemical composition, crystal structure, and mechanical properties of the minerals. Increasing the solution temperature from 25°C to 50°C resulted in a greater packing density, roughly 10 times the stiffness and 4 times the fracture toughness. Collagen surface treatment resulted in roughly 7 times the stiffness along with potential anisotropy in the fracture toughness. Lastly, calcium phosphate minerals appear to pack in low-density and high-density phases on the piezoelectric scaffolds. 

Abstract Mechanically guided, 3D assembly has attracted broad interests, owing to its compatibility with planar fabrication techniques and applicability to a diversity of geometries and length scales. Its further development requires the capability of on‐demand reversible shape reconfigurations, desirable for many emerging applications (e.g., responsive metamaterials, soft robotics). Here, the design, fabrication, and modeling of soft electrothermal actuators based on laser‐induced graphene (LIG) are reported and their applications in mechanically guided 3D assembly and human–soft actuators interaction are explored. Over 20 complex 3D architectures are fabricated, including reconfigurable structures that can reshape among three distinct geometries. Also, the structures capable of maintaining 3D shapes at room temperature without the need for any actuation are realized by fabricating LIG actuators at an elevated temperature. Finite element analysis can quantitatively capture key aspects that govern electrothermally controlled shape transformations, thereby providing a reliable tool for rapid design optimization. Furthermore, their applications are explored in human–soft actuators interaction, including elastic metamaterials with human gesture‐controlled bandgap behaviors and soft robotic fingers which can measure electrocardiogram from humans in an on‐demand fashion. Other demonstrations include artificial muscles, which can lift masses that are about 110 times of their weights and biomimetic frog tongues which can prey insects.