Soil Drencher

One often meets his destiny on the road he takes to avoid it.

Master Oogway Kung Fu Panda

The soil drencher project was actually a project I have known about but never actually done because of the lack of need. You can think of this project as the “Hello World” of hardware, it’s that popular. Granted it won a good amount of hackathons, but the need this time around was that my friend needed a teammate for his project. So of course I decided to be the Watson to his Sherlock and created a components list.

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We agreed that I would handle the electronics and software while he handled the actual mechanism that would water the plants. First thing’s first, I decided that we were going to use an Arduino as our microcontroller. It was the easiest and fastest deployment option we had, not to mention the countless number of tutorials and forums online.

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The Breakdown

We would use a DHT22 sensor to detect humidity (and temperature), and once the humidity drops below 70%, which is displayed on a 16x2 LCD, this would trigger the motor to 55% power. Now the DHT22 sensor will update every 2 seconds (2000 milliseconds) which would be enough time for the water to seep into the soil to increase the humidity and shut switch off the motor.

Being honest I really had no idea about how my friend was going to do the watering part. After I told him I finished with the electronics and software, he showed me what he had come up with. He built a dam inside of a wooden box that I thought was a cajon. There was a door on one of the sides that would let the water pour out after being lifted via a pulley connected to the motors.

The Conclusion

Looking back on the project now, there were several ways we could have improved on our design. We could have added silicon to the door to prevent any water leakage, used stepper motors for better control on the door, and utilizing a $5 water pump for controlled water flow. Either way we were able to impress our professor with our grit and ingenuity and came out with an A+. Although we may look back on this project as a fond memory, I believe what we learned during our journey to build this prototype was priceless.