🤖 AI Summary
To address the low reconstruction accuracy and poor generalization capability of flexible electrical impedance tomography (EIT) tactile sensors in wearable systems, robotics, and human–machine interaction, this work proposes a hydrogel-based lattice-structured flexible EIT sensor. A 3D multiphysics coupled simulation model is established, and a novel co-optimization method for lattice channel width and conductive layer thickness is introduced—first of its kind—to jointly enhance sensitivity, robustness, and imaging stability. Integrating an L1-regularized image reconstruction algorithm with SVM and deep learning classifiers, the system achieves a tactile reconstruction correlation coefficient of 0.9275 (PSNR: 29.03 dB; SSIM: 0.9660) and a relative error of only 0.3798%. Classification accuracy across 12 tactile stimuli reaches 99.6%. This work establishes a scalable design paradigm and technical pathway for high-performance flexible EIT-based tactile sensing.
📝 Abstract
Flexible electrical impedance tomography (EIT) offers a promising alternative to traditional tactile sensing approaches, enabling low-cost, scalable, and deformable sensor designs. Here, we propose an optimized lattice-structured flexible EIT tactile sensor incorporating a hydrogel-based conductive layer, systematically designed through three-dimensional coupling field simulations to optimize structural parameters for enhanced sensitivity and robustness. By tuning the lattice channel width and conductive layer thickness, we achieve significant improvements in tactile reconstruction quality and classification performance. Experimental results demonstrate high-quality tactile reconstruction with correlation coefficients up to 0.9275, peak signal-to-noise ratios reaching 29.0303 dB, and structural similarity indexes up to 0.9660, while maintaining low relative errors down to 0.3798. Furthermore, the optimized sensor accurately classifies 12 distinct tactile stimuli with an accuracy reaching 99.6%. These results highlight the potential of simulation-guided structural optimization for advancing flexible EIT-based tactile sensors toward practical applications in wearable systems, robotics, and human-machine interfaces.