What can the system do?
The system monitors pH, TDS, temperature, humidity and water level. It also includes an air pump for oxygenating the plant roots and a PID controlled peristaltic pump for automatic pH adjustment (which pumps a pH reduction solution).
The Arduino Nano reads the sensor data and controls the air pump and the peristaltic pump, while the Raspberry Pi sends the data to InfluxDB and performs image recognition. I used a pre-trained model for detecting strawberry fruits and I trained a new model on Kaggle for detecting diseased leaves using this dataset.
I used Grafana for visualising the data:
And here's the hardware block diagram:
Enclosure & 3D prints
I've built the system around the IKEA VÄXER hydroponics kit, which is perfect for beginners. What's great about it is that it is easily customisable and there are plenty of resources for it on Thingiverse.
Some parts I found and 3D printed are the following:
- Covers with holes to reduce algae buildup - I had the system running for a while before I used these and I saw a major difference in the algae amount after I added them.
- Lid for the water hole
- Lid - I adapted this one to use it as a sensor mount.
- Raspberry Pi camera adjustable mount
After transferring my strawberry plants from soil to the hydroponic system, they started growing much faster and in just a few weeks I got them to bloom!