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Abstract 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.

Abstract Integrating sensors and other functional parts in one device can enable a new generation of integrated intelligent devices that can perform self‐sensing and monitoring autonomously. Applications include buildings that detect and repair damage, robots that monitor conditions and perform real‐time correction and reconstruction, aircraft capable of real‐time perception of the internal and external environment, and medical devices and prosthetics with a realistic sense of touch. Although integrating sensors and other functional parts into self‐sensing intelligent devices has become increasingly common, additive manufacturing has only been marginally explored. This review focuses on additive manufacturing integrated design, printing equipment, and printable materials and stuctures. The importance of the material, structure, and function of integrated manufacturing are highlighted. The study summarizes current challenges to be addressed and provides suggestions for future development directions.

Abstract A comparative study on the influence of different manufacturing methods (selective laser melting and hot rolling) on the microstructure, mechanical and thermal behaviours of tungsten (W) was presented for the first time. The results indicated that the selective laser melting (SLM) W exhibited a finer grain sizes, a lower strength ductility, hardness and thermal conductivity compared to hot-rolled W. The main reason for this result was that the laser underwent rapid heating and cooling when it was used to melt W powder with high energy density, resulting in large internal stress in the sample after manufacturing. Subsequently, the internal stress was released, leading to the generation of micro-cracks at the grain boundaries, thereby affecting the performance of SLM W samples. In addition, the higher fraction of high-angle grain boundaries (HAGBs) of SLM W was found to be the key factor for intrinsic brittleness. Because the HAGBs are the preferred crack paths, which could promote crack propagation and decrease fracture energy.

Anisotropic surfaces with special wettability under various temperatures are of both fundamental interest and practical importance in many fields. However, little attention has been paid to the surfaces at temperatures between room temperature and the boiling point of water, which is partially due to the lack of a suitable characterization technique. Here, using the MPCP (monitoring of the position of the capillary’s projection) technique, the influence of the temperature on the friction of a water droplet on the graphene-PDMS (GP) micropillar array (GP-MA) is investigated. The friction forces in the orthogonal directions and the anisotropy in the friction decrease when the GP-MA surface is heated up, based on the photothermal effect of graphene. The friction forces also decrease along the pre-stretching direction but increase in the orthogonal direction when the stretching is increased. The change in the contact area, the Marangoni flow inside a droplet, and the mass reduction are responsible for the temperature dependence. The findings strengthen our fundamental understanding of the dynamics of drop friction at high temperatures and could pave the way for the design of new functional surfaces with special wettabilities.

Abstract Integrated sensor–actuators with exciting functionalities, such as action self‐sensing, position self‐sensing, posture self‐sensing, or active sensing, are promising for applications in biomedical device, human–machine interaction, intelligent self‐protection devices, and humanoid robots. Despite recent progress, it remains challenging to achieve a macroscopical integrated sensor–actuator in a material system with microstructures. To address this critical challenge, a 4D printing bioinspired microstructure strategy is reported to design a high‐performance integrated sensor–actuator capable of simultaneous actuation and sensation. Decoupled thermal stimulation and strain sensation is achieved by combining nanocarbon black/polylactic acid composites with bioinspired gradient microgap structures. As a result, printed integrated sensor–actuators can actively touch objects triggered by thermal stimulation and self‐sense the touching state through the resistance change. It is anticipated that the basic design principle underlying this behavior can be used to develop integrated sensor–actuators of various shapes and functionalities to meet desirable applications.