Mechanistic cutting force model has the potential for monitoring micro-milling tool wear. However, the existing studies mainly consider the linear cutting force model, and they are incompetent to monitor the micro-milling tool wear which has a significant nonlinear effect on the cutting force due to the cutting-edge radius size effect. In this study, a nonlinear mechanistic cutting force model considering the comprehensive effect of cutting-edge radius and tool wear on the micro-milling force is constructed for micro-milling tool wear monitoring. A stepwise offline optimization approach is proposed to estimate the multiple parameters of the model. By minimizing the gap between the theoretical force expressed by the nonlinear model and the force measured in real-time, the tool wear condition is online monitored. Experiments show that, compared with the linear model, the nonlinear model has significantly improved cutting force prediction accuracy and tool wear monitoring accuracy.

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.

This study focused on the fabrication and characterization of ammonium metatungstate hydrate (AMT) combined with cobalt(III) acetylacetonate (Co(acac)3)-loaded electrospun micro-nanofibers. The morphologies, structures, element distribution, through-pore size, and through-pore size distribution of AMT/Co(acac)3-loaded PAN/PS micro-nanofibers were investigated by a combination of field emission scanning electron microscopy (FESEM), flourier transformation infrared (FTIR) spectroscopy, energy disperse spectroscopy (EDS), through-pore size analyzer, and so on. These micro-nanofibers have many advantages in their potential application as electro-catalysts. The porous and large thorough-pore will benefit for effective electrolyte penetration, in addition to promoting gas bubbles evolving and releasing from catalyst surface timely.

Flapping wing micro aerial vehicles (FWMAVs) are recognized for their significant potential in military and civilian applications, such as military reconnaissance, environmental monitoring, and disaster rescue. However, the lack of takeoff and landing capabilities, particularly in landing behavior, greatly limits their adaptability to the environment during tasks. In this paper, the purple stem beetle (Sagra femorata), a natural flying insect, was chosen as the bionic research object. The three-dimensional reconstruction models of the beetle’s three thoracic legs were established, and the adhesive mechanism of the thoracic leg was analyzed. Then, a series of bionic design elements were extracted. On this basis, a hook-pad cooperation bionic deployable landing mechanism was designed, and mechanism motion, mechanical performance, and vibration performance were studied. Finally, the bionic landing mechanism model can land stably on various contact surfaces. The results of this research guide the stable landing capability of FWMAVs in challenging environments.

The current research on the removal mechanism of ultra-precision polishing lacks various microscopic understandings of material removal and the process of surface material migration, which hinders the development of ultra-precision polishing technology, especially field constrained abrasive polishing. In order to clarify effects of abrasives at the atomic level on material removal in the field constrained abrasive polishing, a three-dimensional molecular dynamics model is conducted to study the mechanics of ultra-precision polishing on an aluminum (Al) specimen with a diamond abrasive. In order to simulate the real polishing environment, a double abrasive polishing system is designed. The mechanism of material removal was studied by observing the surface topography, surface damage, and coordination number of the working area during polishing. The influence factors of material removal were also investigated by changing the initial velocity, incidence angle, initial force, and relative position of the double abrasives. The results show that the transverse distance and the longitudinal distance between the double abrasives make a slight difference to the number of phase transformation atoms in the double abrasive polishing system, which is directly proportional to the initial velocity, the initial force, the distance between the specimen and its closest abrasive in the Z direction, and the distance between the double abrasives in the Z direction and inversely proportional to the incident angle of the double abrasives. Finally, it is found that the force on the abrasives is the main factor that determines the removal efficiency of the field constrained abrasive polishing.

In engineering, cracks are typically regarded as defects due to enormous stress amplification at tip of the crack. Conversely, scorpion ingeniously utilizes the “risky” near-tip stress field of a crack-shaped slit to accurately detect weak vibration signal without causing catastrophic crack propagation from the slit tip. The present paper focuses on the balance strategy between structural safety and sensing accuracy of slit-based mechanical sensilla. We performed a detailed structural and mechanical property study of tissue around the slit wake utilizing a complementary combination of various experimental methods. The results indicate that there is a special thin surface membrane covering the slit wake and the elastic moduli of the membrane and exoskeleton are 0.562 GPa and 5.829 GPa, respectively. In addition, the ratio of bending stiffness between exoskeleton and membrane tissue is about 8 × 10⁴. The theoretical and simulation analysis show that the surface membrane—with appropriate elastic modulus and bending stiffness—can achieve different forms of deformation with the change of slit width for protecting the mechanosensory structure without sacrificing the sensing accuracy. This finding offers a crucial theoretical basis for the further design of bionic mechanical sensors based on the near-tip stress field of artificial cracks.