Design And Experimental Validation Of A Soft Pneumatic Robotic Device For Neonatal Skin-to-Skin Tactile Therapy

Skin-to-skin tactile stimulation plays a critical role in the neurodevelopment of premature infants, contributing to improved physiological stability, sensory integration, and parent–infant bonding. However, the delivery of consistent tactile therapy in neonatal intensive care units is often limited by the availability of trained personnel and the inherent variability of manual application. This creates a need for assistive technologies capable of reproducing clinically relevant tactile stimuli in a controlled and repeatable manner. This work presents a soft pneumatic robotic system designed to replicate clinically inspired tactile stimulation for neonatal therapy. The proposed approach integrates experimental characterization of manual tactile interactions, pneumatic system modeling, and closed-loop control. Force measurements obtained from a neonatology specialist were used to define clinically grounded stimulation levels, with mean values of 0.594 N (light) and 1.267 N (moderate). These values were mapped to actuator pressure through experimentally identified linear relationships between force, pressure, and electrical current, enabling the definition of pressure-based control references. A deadband-based control strategy with integrated current-based protection was implemented to regulate actuator pressure within therapeutic bounds. Experimental results demonstrate that the proposed controller achieves up to 76.1% time within the target pressure band, reducing mean pressure error by approximately 78% compared to a baseline approach, while maintaining robust performance under varying mechanical interface conditions. These results demonstrate the feasibility of translating clinically derived tactile stimulation into controlled pneumatic actuation using a soft robotic platform. The proposed system provides a reproducible and safe approach for delivering tactile therapy, addressing limitations in clinical resource availability and supporting the development of assistive technologies for neonatal care.