A smart finger patch with coupled magnetoelastic and resistive bending sensors

In the era of Metaverse and virtual reality(VR)/augmented reality(AR),capturing finger motion and force interactions is crucial for immersive human-machine interfaces.This study introduces a flexible electronic skin for the index finger,addressing coupled perception of both state and process in dynamic tactile sensing.The device integrates resistive and giant magnetoelastic sensors,enabling detection of surface pressure and finger joint bending.This e-skin identifies three phases of finger action:bending state,dynamic normal force and tangential force(sweeping).The system comprises resistive carbon nanotubes(CNT)/polydimethylsiloxane(PDMS)films for bending sensing and magnetoelastic sensors(NdFeB particles,EcoFlex,and flexible coils)for pressure detection.The inward bending resistive sensor,based on self-assembled microstructures,exhibits directional specificity with a response time under 120 ms and bending sensitivity from 0°to 120°.The magnetoelastic sensors demonstrate specific responses to frequency and deformation magnitude,as well as sensitivity to surface roughness during sliding and material hardness.The system’s capability is demonstrated through tactile-based bread type and condition recognition,achieving 92%accuracy.This intelligent patch shows broad potential in enhancing interactions across various fields,from VR/AR interfaces and medical diagnostics to smart manufacturing and industrial automation.

Stretch Bending of Z-section Stainless Steel Profile

The stretch bending properties of a new Z-section stainless steel profile were investigated by simulation.The causes of the forming defects,such as section distortions and poor contour precision,were analyzed,and the corresponding controlling methods were proposed.The results show that the main forming defects for the stretch bending of the Z-section profile were the flange sagging,the sidewall obliquing inward,the bottom surface upwarping,and the bad contour accuracy;the cross-section distortions were mainly induced by the shrinkage of the sidewall,which could be eliminated by increasing the sidewall height of the profile reasonably;the poor contour precision was mainly due to springback,which could be controlled by modifying the die surface based on the springback amount;for the investigated bending beam,the proper sidewall height compensation was 2mm,and the suitable die surface modification amount was 1.2times of the springback amount,when the elongation was 10% of the initial profile length.Stretch bending tests were conducted on a new type of die with adjustable bending surfaces,and high quality components were achieved,which verified the effectiveness of the defect controlling measures.