VeCare: Statistical Acoustic Sensing for Automotive In-Cabin Monitoring.

On average, every 10 days a child dies from in-vehicle heatstroke. The life-threatening situation calls for an automatic Child Presence Detection (CPD) solution to prevent these tragedies. In this paper, we present VECARE, the first CPD system that leverages existing in-car audio without any hardware changes. To achieve so, we explore the fundamental properties of acoustic reflection signals and develop a novel paradigm of statistical acoustic sensing, which allows to detect motion, track breathing, and estimate speed in a unified model. Based on this, we build an accurate and robust CPD system by introducing a set of techniques that overcome multiple challenges concerning sound interference and sensing coverage. We implement VECARE using commodity speakers and a single microphone and conduct experiments with infant simulators and adults, as well as 15 young children for the real-world in-car study. The results demonstrate that VECARE achieves an average detection rate of 98.8% with a false alarm rate of 2.1% for 15 children in various cars, boosting the coverage by over 2.3x compared to state-of-the-art and achieving whole-car detection with no blind spot.