Hello!
I have a 8x10meters greenhouse full of flowers and currently I water them with a high water tank and pipes.
I want to make a smart irrigation system as my bachelor degree project (I am a CS student), and I need some ideas. I won't have electricity near the greenhouse for the next few months, but I do have Wi-Fi from the neighbors over there (I refill the water tank with a gasoline generator every week).
My idea so far is this: for the purpose of the degree project, I will limit the system to 4 rows of plants (each row being 10m long), each having a soil moisture sensor at the end (where the water on the pipe has the lowest pressure) and a valve for each pipe, somehow connected to an arduino board. I want to water each row until a given moisture and a mobile app to monitorize it (or change it, or any other feature you could suggest).
I don't know how should I do it. Can you please help me with the hardware part for now? What can I use to make this possible? Can I connect it to a mobile app? (Should I use batteries, more arduinos, how many valves ?).
(Until I will have electricity on that property, I won't have to run the system 24/7, just a few times to show how it works. I will expand it over the next year when I'll have more income from the flowershop).
Unfortunately, widely available soil moisture sensors are unreliable. Few hobbyists have much luck using them to control irrigation sensors due to calibration and reliability problems. And failures can lead to catastrophic floods.
Especially on the hobby market, soil sensors are plagued with problems like rapid corrosion, measurements vary wildly with soil type, age, insertion, soil wetting patterns, etc. If you look through this and other hobby forums, you will find endless complaints.
Since that is the primary weakness of your proposed automated system, spend some time talking to greenhouse professionals, and do your own research.
There are literally hundreds of this project, at least one here on Project Hub. NOTE: I have yet to hear of a soil moisture sensor that works for more than a few days. Instead, track soil temperature in order to calculate evaporation from a known start point, also use the humidity in the calculation.
Does your instructor know you are not doing the work?
Would measuring humidity (DHT, not soil-spike device) at the surface and high above the surface show a difference, relating to soil moisture content ? That is to say, if the soil has no more water to evaporate, would soil-air and air-air have the same humidity, or is it always the same? Experiment?
p.s. Reading sonofsy's post with soil temperature versus ambient temperature. I agree with that.
I will note that about the sensors.
During university, our curriculum didn’t really focus on hardware, and I’m quite a beginner. My coordinator gave me the idea and told me to use this kind of sensors and valves etc., but focus on the app part, they are more interested in that.
Also for my greenhouse…I will stick to the manual watering system if the system can not be done, but I would love to make it nicer
