🤖 AI Summary
To address poor cross-device compatibility and inconsistent evaluation in smartphone-based photoplethysmography (PPG) heart rate monitoring—stemming from device fragmentation—this paper introduces the first high-throughput, automated benchmarking platform capable of parallel testing across 12 devices. We propose a novel synthetic PPG video generation method that enables precise control over ground-truth heart rate and signal quality. Integrated with multi-device synchronization, video playback-driven stimulation, and automated data acquisition, the platform employs clinically validated algorithms to ensure standardized bench testing. Experimental evaluation spans 20 mainstream smartphone models; under ANSI/CTA compliance criteria, the platform achieves 100% accuracy in heart rate classification. It attains a mean absolute percentage error of only 0.11% for heart rate estimation and a PPG waveform correlation coefficient of 0.92. This work establishes a reproducible, scalable, and cross-platform performance evaluation paradigm for mobile health applications.
📝 Abstract
Smartphone-based heart rate (HR) monitoring apps using finger-over-camera photoplethysmography (PPG) face significant challenges in performance evaluation and device compatibility due to device variability and fragmentation. Manual testing is impractical, and standardized methods are lacking. This paper presents a novel, high-throughput bench-testing platform to address this critical need. We designed a system comprising a test rig capable of holding 12 smartphones for parallel testing, a method for generating synthetic PPG test videos with controllable HR and signal quality, and a host machine for coordinating video playback and data logging. The system achieved a mean absolute percentage error (MAPE) of 0.11% +/- 0.001% between input and measured HR, and a correlation coefficient of 0.92 +/- 0.008 between input and measured PPG signals using a clinically-validated smartphone-based HR app. Bench-testing results of 20 different smartphone models correctly classified all the devices as meeting the ANSI/CTA accuracy standards for HR monitors (MAPE <10%) when compared to a prospective clinical study with 80 participants, demonstrating high positive predictive value. This platform offers a scalable solution for pre-deployment testing of smartphone HR apps to improve app performance, ensure device compatibility, and advance the field of mobile health.