Striking a balance between sensitivity and detection range while ensuring stability under extreme temperatures remains a formidable challenge in the design of flexible pressure sensors. To address this issue, we draw inspiration from the multi-gradient architectures of nature and propose a bottom-up self-assembly strategy. By leveraging a meticulously orchestrated multi-step approach that encompasses electrospinning, sequential freezing, and thermal imidization, we successfully fabricate a polyimide nanofiber/carbon nanotube dual-gradient aerogel with a dynamic stiffness transition from flexible to rigid states. Experimental results highlight notable properties of the dual-gradient aerogel, which exhibits an ultralow density (0.023 g cm⁻³), efficient thermal insulation (28 mW m⁻¹ K⁻¹), and reliable compressibility and fatigue resistance. Moreover, it establishes a favorable equilibrium between sensitivity (156 MPa⁻¹) and an extensive detection range (223 kPa). Notably, the combination of thermal resilience (−196 °C to 533.30 °C) and mechanical stability enables performance that is comparable to, or in some aspects surpasses, that of conventional flexible sensing materials. This dual-gradient aerogel provides both effective thermal insulation and high-precision physiological monitoring under extreme conditions, offering integrated thermal protection and real-time astronaut health assessment in spacesuits.

Introducing nonuniform thickness has shown promising potential in enhancing the energy absorption of thin-walled tubes. However, existing studies were focused on the axial loading, with little attention being paid to the oblique loading condition. In this paper, the energy absorption performance and the deformation modes of the circular tubes with gradient thicknesses under oblique loads are investigated. Finite element simulations and experiments were carried out for both uniform-thick and gradient-thick tubes under the axial and oblique loads, and satisfactory agreement was achieved betweent the numerical and the experimental results. The validated finite element models were used to investigate the effects of the thickness gradient and loading angle on the deforamtion modes and the energy absorption. The results highlight the advantages of the gradient-thickness tubes in improving the energy absorption performance under the oblique loading condition, especially at a larger loading angle. A novel progressive bending deformation mode was observed for the tube with large thickness gradient at a loading angle larger than 15°, which is beneficial for the energy absorption performance.

1. With the rapid progress of advanced manufacturing technologies and the introduction of bioinspired design principles [1–5], mechanical metamaterials, artificially architected structures whose pr...