Wearable HRV Stress Detection and Intervention for Sensory Overload in Children with Autism in the Philippines

Children with Autism Spectrum Disorder (ASD) are often highly susceptible to sensory overload, triggered by factors such as excessive noise, unfamiliar environments, or challenges in emotional regulation. Sensory overload can result in intense reactions, including tantrums and meltdowns, which may escalate into heightened anxiety, withdrawal, self-stimulatory behaviors, or even impaired communication. These responses make it difficult for caregivers to manage and comfort the child effectively and can hinder their learning, social interactions, and emotional well-being. Existing assistive technologies, such as wearable devices, have been developed to detect sensory overload and provide real-time information to parents. This study proposes an innovative assistive technology system, designed to enhance the management of sensory overload in children with ASD. The system integrates a wearable device equipped with a DFRobot Gravity photoplethysmography (PPG) heart rate sensor, using Arduino with an ESP32 microcontroller. The wearable continuously measures heart rate and derives heart rate variability (HRV) metrics, which serve as physiological indicators of stress associated with sensory overload. Validation experiments were conducted with five high-functioning children with ASD, where heart rate and HRV stress scores were measured before and after controlled physical activity, using wrist and finger sensor placements. Comparative analysis with a commercial wearable band showed a strong correlation (r = 0.97) and a minimal mean difference in BPM of 2.00, highlighting the feasibility of our HRV-based stress wearable in real-world use. Our system aims to improve stress management and strengthen communication between children with ASD and their caregivers in educational and everyday settings.