Low-Cost Semi-Automatic Design of Tactile IoT for Blind Students

Blind and low-vision (BLV) students face barriers when educational content depends on graphical structures that conventional assistive technologies cannot effectively convey. We introduce a low-cost approach for the development of interactive tactile IoT graphs for accessible education. We propose a novel semi-automatic, human-in-the-loop process to jointly generate, from a 2D graph image, two graph-specific and geometrically aligned components: an assembly-ready 3D tactile board and a PCB/feed-line sensing layer. The architecture integrates these outputs with detachable resonant nodes and a portable reader to enable passive RF-based interaction sensing and audio feedback. The workflow maintains low effort for non-specialist users and produces assembly-ready tactile/sensing pairs with perfect topological fidelity on the tested graphs. Full-wave electromagnetic simulations demonstrate that touch on different nodes induces localized and clearly distinguishable impedance perturbations, while progressive displacement along an edge yields a monotonic response. A preliminary physical prototype and an initial accessibility evaluation with a blind user further support the practical viability of the approach. These results provide an early foundation for battery-free, low-complexity tactile IoT systems.