Acquisition of Tactile Information via Piezoresistive Array for Neuromorphic Feedback in Robotic Prostheses

Restoring tactile perception in upper-limb prostheses is essential for enabling natural and precise object manipulation. This work presents a bioinspired hardware interface designed to acquire and process tactile information from a piezoresistive 4×4 sensor array in real time. The sensing approach is based on the behavior of rapidly adapting mechanoreceptors (FA-I afferents), which encode transient pressure variations during contact events. Voltage samples acquired via a STM32F767ZI microcontroller using ADC channels in circular DMA mode were converted into input currents for the Izhikevich spiking neuron model, which in turn generated biologically inspired spike trains. These spikes were then modulated and outputted as digital pulses on GPIO channels, which can be easily interfaced with an electrical stimulator to provide somatosensory feedback to a prosthesis user. The system was evaluated under different pressure and texture conditions, demonstrating low-latency response and stable operation for continuous tactile acquisition. The results highlight the feasibility of integrating neuromorphic tactile encoding into prosthetic devices, paving the way for more natural and effective human–machine interaction.