Daniel Fischer's redesign of the kit. One ESP32-S3 board with WiFi replaced the Arduino Uno and Raspberry Pi, with more sensor connectors, optional LoRa and…
Project Report from Project Lead and Board inventor Daniel Fischer:
When I joined the project, the data acquisition was based on an Arduino UNO board with interface shield to connect sensors. The sensor data was transferred to a Raspberry Pi microcomputer and transmitted to the Teleagriculture website via LAN connection.
After I became familiar with the project in December 2022 and analyzed the Arduino Uno / Raspberry Pi setup, I noticed some potential for improvement.
The advantages of the old boards are: • the Arduino code could be made relatively short and clear • easy to display data via the Raspberry Pi and a connected screen.
But the disadvantages seemed to outweigh them for me: • Complex setup / user has to adapt and compile the program code. • There could be more connectors. • You need an additional Raspberry Pi, which since the pandemic has had disadvantages in both price and availability. • The high power consumption of the Raspberry Pi makes battery-powered setups difficult.
So I made plans for an integrated system, based on the ESP32 Microcontroller.
The ESP32 microcontroller is actually cheaper than Arduino Uno and do not need a Raspberry Pi to connect to the internet. Which means that you get a more powerful board for a lower price. At the level where you use your existing Arduino skills to work with the ESP32, you can treat the ESP32 as a supercharged Arduino Uno: faster, with WiFi on board and far more memory.
The ESP32 has more I/O pins compared to the Arduino Uno, which means that it can fit more sensors and modules because it has more GPIO pins. This also means that it has more PWM and analog pins.
So I developed a sensor board with these features: • ESP32-S3 microcontroller with WiFi onboard and 8MB storage • 3x analog sensor connectors • 3x 1-Wire sensor connectors • 4x I2C sensor connectors • 1x 5V-I2C sensor connector • optional TFT display connected via SPI bus • optional Olimex LoRa SX1276 module connected via SPI bus • optional connection to WaveShare Solar Power Manager board
To compensate for the complexity of the microcontroller used and to keep the entry barriers for the users as low as possible, I decided to integrate a captive portal with Web UI. So less experienced users who still want to measure data can quickly try out sensors and experiment with the board's capabilities. Without having to install a microcontroller programming environment and compile programs. This Web UI also offers a nice way to setup the board and adapt new connections to WiFi or LoRa networks. In addition the Web UI can be used to upload new firmware.
More info can be found on our GitLab Community Page. You can order a board in the shop, or contact us @ [email protected]