Numerous plants evolve ingeniously microcantilever-based hairs to ultra-sensitively detect out-of-plane quasi-static tactile loads, providing a natural blueprint for upgrading the industrial static mode microcantilever sensors, but how do the biological sensory hairs work mechanically? Here, the action potential-producing trigger hairs of carnivorous Venus flytraps ( Dionaea muscipula ) are investigated in detail from biomechanical perspective. Under tiny mechanical stimulation, the deformable trigger hair, composed of distal stiff lever and proximal flexible podium, will lead to rapid trap closure and prey capture. The multiple features determining the sensitivity such as conical morphology, multi-scale functional structures, kidney-shaped sensory cells, and combined deformation under tiny mechanical stimulation are comprehensively researched. Based on materials mechanics, finite element simulation, and bio-inspired original artificial sensors, it is verified that the omnidirectional ultra-sensitivity of trigger hair is attributed to the stiff-flexible coupling of material, the double stress concentration, the circular distribution of sensory cells, and the positive local buckling. Also, the balance strategy of slender hair between sensitivity and structural stability (i.e., avoiding disastrous collapse) is detailed revealed. The unique basic biomechanical mechanism underlying trigger hairs is essential for significantly enhancing the performance of the traditional industrial static mode microcantilever sensors, and ensure the stability of arbitrary load perception.
Ling Cai,Guangxue Chen,Junfei Tian,Bin Su,Minghui He
Ionic skin with a high performance has been extensively explored due to its ability to convert external stimuli into obvious electrical signals for wearable electronics and intelligent detection. However, due to the unmatched Young’s moduli between the elastic substrate and the conductive layer, rapidly manufacturing durable ionic skin with ultrasensitivity over a wide range of pressures is still a great challenge. Here, we report a new strategy of 3D printing polymerizable deep eutectic solvent (PDES) for the manufacture of highly sensitive bioinspired ionic skin over a wide range of pressures via photopolymerization shrinkage formed submicrometer-scale protrusions on bioinspired skin structures. The 3D patterned poly(PDES) ionic skin (interlocked pyramid type with submicrometer protrusions) can realize “all-in-one” ability with high transparency, compressibility, and intrinsic conductivity, displaying ultrabroad range pressures (0.6 Pa–2 MPa) with superhigh sensitivity (348.28 KPa–1) and high electrical durability (at 0.35 MPa for 45 000 cycles). Furthermore, these excellent abilities allow as-prepared ionic skins to serve as visually detected pressure sensors for precision instruments, providing great potential in flexible wearable monitoring equipment and human-computer interaction.
危险品化学品经营许可证（带存储）