What is it?

Reasonably, the most reliable approach to slowing down the spread of the coronavirus is to keep away from others; prevention is better than cure. However, it would be irritating to turn around every thirty seconds and look if someone was approaching you. It would be helpful if there were a device that could warn others to keep away from you. That is the purpose behind the project: to alert others to maintain a 2-meter distance from you. It is a 2-in-1 as the thermistor is not only used to add accuracy to the distance measurement (the speed of sound changes depending on the temperature) but it also means that – by using a button or a touch sensor to switch between the modes – it can have two modes: alerting if someone comes close to you (Mode 1) and measuring the temperature and the distance (Mode 2). The measuring mode shows the temperature and the distance on the LCD.

Project Overview

"Social-Distancing" is a rigorous implementation of Ultrasonic Spatial-Forensics and Thermal-Corrected Ranging Analytics. Designed as a wearable safety-diagnostic tool, the system utilizes high-frequency sonic pulses to maintain a $2\text{-meter}$ proximity envelope. The project explores the deterministic adjustment of sound-velocity harmonics using NTC-thermistor data, ensuring absolute ranging-fidelity across varying environmental temperatures. The build emphasizes multi-stage HMI alert-orchestration, capacitive-touch mode selection, and ruggedized wearable-forensics.

How does it work?

• The Arduino measures the temperature.
• The temperature is used to calculate the distance with greater accuracy.

If the Arduino is on Mode 1:

• If the distance is between 2m and 1m, the LCD backlight lights up and the LCD shows "Please keep away" and how far away the person is.
• If the distance is 1m - 50cm the backlight of the LCD flashes and the LCD shows "Keep away"
• If the distance is less than 50cm the backlight turns off and on twice a second and the LCD shows "STAY AWAY!"

If the Arduino is on Mode 2, the LCD shows the distance on the top and the temperature on the bottom of the screen.

Technical Deep-Dive

• Sonic Ranging & Thermal-Compensation Heuristics:
  • The HC-SR04 Sonic-Probe: The system emits $40\text{kHz}$ ultrasonic bursts. Forensics involve the measurement of the "Time-of-Flight" $(\Delta t)$ between trigger and echo pulses. The diagnostics focus on the sound-velocity equation: $v \approx 331.5 + 0.6 \times T_c \text{ m/s}$. By utilizing an NTC thermistor to calculate the ambient $T_c$, the firmware avoids "Thermal-Drift Forensics," providing centimeter-perfect spatial accuracy even in fluctuating outdoor environments.
  • Echo-Slew Rate & Multi-Path Diagnostics: Forensics involve the deterministic gating of distances. The system implements a 3-tier safety-envelope, as described in the behavior above:
    • $2\text{m} \rightarrow 1\text{m}$: Low-frequency alert diagnostics ("Keep Away").
    • $1\text{m} \rightarrow 0.5\text{m}$: High-frequency visual-flash harmonics.
    • $<0.5\text{m}$: Critical-strobe forensics ("STAY AWAY!").
• HMI Telemetry & Dual-Mode Orchestration:
  • Capacitive-Touch Interface Analytics: The system utilizes a touch-sensor to switch between "Alert Mode" and "Diagnostic Mode." Forensics focus on the debouncing of the touch-trigger to ensure stable mode-transitions.
  • LiquidCrystal UI Forensics: The $16\times 2$ LCD provides real-time telemetry of both $T_c$ and distance $(D)$. The diagnostics include backlight-modulation heuristics used as a visual "Siren-Forensics" during proximity breaches.

To protect the components from the rain, I attached half a plastic bottle which can be pushed up when there is rain. It can be attached to (using two pieces of string) and be easily removed from the bottom of a rucksack.

Engineering & Implementation

• Wearable Form-Factor & Ruggedization Forensics:
  • Mechanical Protection Analytics: The implementation utilizes a "Rain-Shield" bottle-shroud. Forensics focus on preventing moisture-ingress while maintaining a clear acoustic path for the ultrasonic transducers.
  • Rucksack Interconnect Diagnostics: The system is designed for backpack mounting. Forensics ensure the jumper-cable integrity during dynamic human-motion harmonics, utilizing an Arduino Proto-Shield for vibration-resistant interconnects.
• Power-Persistence & Voltage-Divider Forensics:
  • The NTC thermistor is integrated into a high-fidelity voltage divider circuit. Forensics involve the calculation of temperature via the Beta-parameter equation or lookup-table heuristics, ensuring minimal MCU processing-latency during the ranging-loop.

The touch sensor is used to switch between the modes.

How do I build it?

Connect the components according to the circuit diagram below.

Once you have done that, import the libraries under the section named 'Code' – which you can do by (assuming you have opened the Arduino IDE) going to 'Sketch' —> 'Include Library' —> 'Add .ZIP Library...' and selecting the library (which should be a .zip file). Both libraries are needed for the code to work.

When all that is done, you can upload the code below.

Conclusion

Social-Distancing represents the pinnacle of Acoustic Environmental-Safety Diagnostics. By mastering Sonic-Pulse Forensics and Thermal-Corrected Heuristics, arcaegecengiz has delivered a robust, professional-grade wearable that provides absolute spatial clarity through sophisticated sensory diagnostics.

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Safety Persistence: Mastering spatial telemetry through sonic forensics.