In the last month I built a multisensor capable of measuring temperature, humidity, light and CO2 level, using an ESP32 card so I can then also receive data from different MiFlora sensors via BLE.
Currently the installation is in a prototyping box. Not satisfied with the size of the box and the mess in the wiring I decided to develop a PCB and include the sensors directly on the board in order to reduce the size as much as possible.
I also added an IR transmitter and receiver so that I could control other devices such as a television or a stereo system.
The board has a quite small size of 35x40mm and has the following components and functions:
- ESP32 WROOM 32D module as main controller providing WIFI and BLE capabilities
- HTU21D for temperature and humidity, with a Typical humidity accuracy of ±2% and ±0.3C for temperature
- BH1750 for light level, with a range of 1 to 65535 lux
- MH-Z19 for CO2 level, with a range of 0 to 5000 ppm
- An IR transmitter and receiver to control IR devices
- An USB to serial IC to provide an easy way to program the ESP32 via USB cable
I’m currently waiting to receive the first batch of the boards so that I can test them. Once tested I will share schematics and gerber, and if there is interest, I could have a number of boards produced and sell them already assembled.
I also planned to develop an enclosure for the board to be 3d printed to protect and be able to mount the sensor somewhere.
Updates to follow, in the meantime let me know if you have questions/advice.
Update: Since many are interested I will consider the option of opening a store on Tindie. Since I’m still studying and free time is quite limited, I still have to evaluate how to do it, I’ll let you know.