An IoT-Based Smart System with an MQTT Broker for Individual Patient Vital Sign Monitoring in Potential Emergency or Prehospital Applications

Figure 4

Electronic circuits of all devices discussed in this paper. (a) shows the RFID controller circuits for the MCU (ESP32), a 7″ TFT touch screen (Nextion USART HMI) manufactured by ITEAD STUDIO, and an RFID reader (MFC522) manufactured by NXP Semiconductors. (b) shows the circuits of the blood pressure device for the MCU (Arduino MKR1000), the LCD2004 display, the blood pressure measurement module with an embedded ARM-based MCU modified from a commercial blood pressure product, a user-triggered push button, and a status-indicator light-emitting diode (LED). (c) shows the circuits of the oxygen device for the MCU (Arduino MKR1000), the LCD2004 display, the pulse oximeter with an embedded ARM-based MCU as its controller, a user-triggered push button, and a status-indicator LED. (d) shows the circuits of the head temperature device, which are separated into two parts to include the whole device. The first part is the head temperature probe, which includes the MCU (Arduino Nano), the IR thermo sensor (Nextion, model: LX90614), manufactured by Adafruit Industries, and the status-indicator LED. The second part consists of the controllers, which include an MCU (ESP32), a 0.96″ OLED display manufactured by Seed Technology Co., Ltd., a user-triggered push button, and a status-indicator LED. (e) shows the circuits of the body temperature device, which include the MCU (ESP32), a 0.96″ OLED display manufactured by Seed Technology Co., Ltd., the high-precision thermistor integrated with a 24-bit ADC developed by this research, a user-triggered push button, and a status-indicator LED. (f) shows the circuits of the body-scale device, which are separated into two parts to include the whole device. The first part is the weight detector, which includes the MCU (Arduino Nano); four load cells (maximum of 50 kgW each) combined with a Wheatstone bridge as the weight sensor, which is located under tempered glass to support a human standing on it; and an RF transmitter module (model: MUART0-B) to send data to the weight controller, manufactured by Sunplus Innovation Technology Inc. in Taiwan. The second part is the weight controller, which includes an MCU (ESP32); an LCD2004 display; an RF transmitter module (model: MUART0-B) as the data receiver for the weight detector, manufactured by Sunplus Innovation Technology Inc. in Taiwan; a user-triggered push button; and a status-indicator LED.