Hierarchical strain-isolation architecture inspired by campaniform sensilla for anti-interference pressure sensing

Flexible pressure sensors have been widely utilized in wearable electronics and robotic systems. However, their practical deployment is hampered by mechanical strain interference, which severely compromises pressure sensing accuracy. Here, we report a campaniform sensilla-inspired flexible pressure sensor (CIFPS) that successfully achieves anti-mechanical interference sensing through a hierarchical biomimetic design. The CIFPS integrates the spindle microstructure, the ring-pit architecture, and the interfacial adhesive layer to synergistically suppress small-strain noise and large-strain-induced signal distortion. Experiments show that the CIFPS exhibits excellent anti-mechanical interference performance, with signal relative standard deviations (RSDs) of 5.61% and 5.55% under small stretching and bending disturbances, respectively, and a signal peak-response RSD of only 2.17% under 28% stretching strain interference. Meanwhile, it retains over 98% pressure sensitivity under 28% strain and shows stable output over 80,000 loading cycles. When integrated into a soft sponge-assisted robotic gripper, the CIFPS enables non-destructive strawberry harvesting and classification of size and maturity. Overall, this work offers an effective biomimetic design strategy for constructing anti-interference pressure sensors, providing broad prospects for intelligent agriculture, soft robotics, and wearable electronics.