Project description

Soil Sensing is a device to measure soil moisture and soil temperature on two different depths.

This device is to be used and tested on a research project where potatoes will be planted on both soil and seaweed and compared on different parameters. By measuring the temperature and the moisture of the soil and the seaweed over a growing season we hope to better understand the growth environment and the outcome.

Read more about the project here:

Lokal naturtang - sanket, forarbejdet, og afsat

The device records sensor data, time and date on a SD-card. The data can also be accessed by logging into the devices access point trough WiFi.

Components

• 1 x ESP32 TTGO T1 with SD-card reader
• 2 x waterproof DS18B20 sensor
• 2 x 4,7k resistor
• 1 x Capacitive Soil Moisture Sensor - Corrosion Resistant (make it water resistant, see here)
• 1 x GPS NEO-6M

Wiring

Temp sensor

On my project i connected the two temperature sensors on:

DATAPIN 19

DATAPIN 18

Moisture sensor

On my project i connected the moisture sensors on:

DATAPIN 33

GPS

On my project i connected the moisture sensors on:

GPS-TX 16

GPS-RX 17

Final product

Code

The Arduino code can be downloaded from GitHub

https://github.com/saradaugbjerg/soilsensing

Access data via access point

1. Connect the device to power via USB cable
2. Log on WIFI
   
   a. Name: SoilSensing1
   
   b. Password er: 123456789
3. Open the browser and navigate to: 192.168.1.1

The page shows the last 10 readings, so one easier can check if the latest data is ok.

By pressing the “Download” button, one can download all the readings stored on the SD-card as a .txt file.