Wearable distance monitor based on ESP8266

After the outbreak of COVID-19, the World Health Organization (WHO) issued basic protective measures against the new coronavirus, such as maintaining good personal hygiene habits and wearing masks... In addition, WHO experts also recommended that people Maintaining appropriate social distance (especially with people who are coughing or sneezing) requires at least one meter of separation.
Sahil Rastogi and his Random Stuff We Make! (RSWM!) team have developed a small device that can help people maintain appropriate social distance as recommended by the WHO.
The RSWM! team is composed of engineers and makers in Delhi, India. They are committed to developing interactive, innovative and easy-to-make projects to turn some ideas into reality. The team focuses on 3D printing, Arduino, embedded electronics, RGB lights, interactive installations, robotics, APP development and product design. In the current situation of the rapid spread of the new coronavirus epidemic, the RSWM! team developed this distance monitor to prevent the spread of the virus by reminding people to maintain appropriate social distance.
The wearable distance monitor they developed will change the color of the light and sound a warning tone when someone comes within one meter of you, reminding you to keep your distance.
Hardware components:
A 360 mAh 1S 30C/60C lithium polymer battery pack (LiPo)
A TP4056 1A lithium-ion battery charging module with current protection - mini USB
A SparkFun ultrasonic sensor HC-SR04
A buzzer
An ESP8266-based NodeMCU ESP8266 Breakout Board
One Adafruit NeoPixel LED Ring: WS2812 5050 RGB LED

Software APP and online services:
Arduino IDE

Tools:
Soldering iron (universal)
Hot glue gun (universal)

This wearable thermometer based on ESP8266 NODE MCU and Adafruit NeoPixel LED ring played an important role during the spread of the global epidemic.