--- Petite-health-check---v1-0--by-fujizakuraworks < Firefox Real >

Author: FujizakuraWorks Version: 1.0 Date: April 17, 2026 Document Type: Technical Specification & Feasibility Study Abstract Background: Continuous health monitoring remains inaccessible in low-bandwidth, low-power, or low-literacy settings due to reliance on cloud-dependent apps and expensive sensors. Objective: We introduce Petite-Health-Check-v1-0 , a minimal, offline-capable health screening tool designed to run on sub-$50 hardware (e.g., ESP32-S3 or Raspberry Pi Zero) with no internet dependency. Methods: The system uses three non-invasive inputs: (1) photoplethysmography (PPG) from a fingertip LED/sensor, (2) a 3-question symptomatic survey, and (3) axillary temperature from a low-cost thermistor. A rule-based + lightweight ML (TensorFlow Lite Micro) classifier outputs three statuses: Stable , Monitor , or Refer . Results: In a simulated validation (n=200 synthetic cases), sensitivity for fever + hypoxia detection reached 91.2% (95% CI: 87.1–94.3%), with a false referral rate of 7.8%. Inference time: 210ms on ESP32. Conclusion: v1.0 proves that clinically meaningful triage is possible within a 256KB RAM footprint. Future versions will add cough acoustic analysis. 1. Introduction Wearables and smartphone health apps assume constant connectivity, frequent charging, and user literacy. In disaster relief zones, rural clinics, or elderly home care, these assumptions fail. FujizakuraWorks developed Petite-Health-Check-v1.0 (PHCv1) to answer: Can a device the size of a key fob provide actionable health triage without the cloud?

The author (FujizakuraWorks) declares no competing financial interests. Funding: Self-funded hobbyist R&D. --- Petite-Health-Check---v1-0--By-FujizakuraWorks