Students Hamed Kiany and Xiang Ming Fan Turn to the Espressif ESP8266 for an Environmental Monitor
Low-cost, low-power Wi-Fi-connected microcontroller powers this environmental monitoring and control project.
Electronic engineering students Hamed Kiany and Xiang Ming Fan have designed an environmental monitoring and control system powered by the low-cost Espressif ESP8266 microcontroller — and housed in an attractive 3D-printed case.
"This project was developed for 'Electrónica Creativa' (Creative Electronics), a BEng Electronic Engineering 4th year module at the University of Málaga, School of Telecommunications," its creators explain of the environmental monitor. "This project uses the ESP8266 microcontroller to build a system that checks and controls temperature from a distance. It also sends updates and takes commands through Telegram messages."
The project is based around an Espressif ESP8266 microcontroller module, providing both the controlling logic and a Wi-Fi connection for remote monitoring and control. It's hooked to the common, low-cost DHT11 combined digital temperature and humidity sensor — plus a MOSFET, designed to give it the ability to control external devices either based directly on its own environmental readings or in response to remote control commands. An internal battery powers the project without wires, with all the hardware housed in a smart-looking 3D-printed case.
The project's firmware is written in the Arduino IDE, and includes a library designed to have the device appear as a bot on the Telegram instant messaging system. This provides an easy way to monitor readings from the device and also to send it commands — turning connected devices on and off manually using the MOSFET — and to monitor the charge level of the batter.
"Additionally, the device is designed with deep sleep mode for power-saving between readings and supports Over-the-Air (OTA) updates," Kiany adds, "so firmware can be easily updated without needing to connect the device physically."
Full instructions are provided on Instructables, with source code and files for the 3D-printable case provided on GitHub under the reciprocal GNU General Public License 3.
