Irrigation (sprinkler) systems have come a long way since their inception, and even further since the advent of modern electronics, and with the modern Internet and the beginings of the Internet of Things (IoT) revolution they are getting smarter and are able to do more. One example of this is that where a “modern” controller can tell if it is raining, or has rained in the past period through the use of a rain guage, IoT devices such as the OpenSprinkler can now use forcast weather from the internet to make a decision about the watering. Linking this with things such as moisture sensor data can make these systems even smarter. This is however one thing that seems to be missing, the “smart” solenoid.
I am not a gardener by choice per-sey but more by nececcity, wanting to take more control of the food I and my family eat requires growing our own, which whilst easy in some respects, does chew up a lot of time.
Solonoids themselves are quite simple devices they use a magnetic coil to retract a metal (normally iron) core against a spring (which opposes the coil so the solonoid goes back to “rest” when the electrical current is no longer applied) to open or close a gate, if the gate is closed, water does not pass, open the gate, and the water flows through. Nice and simple.
What is not so simple however is the current requirement to run an entire cable pair, yes there are ways of theoretically doing n+1 (n being the number of solonoids) but in general its one solonoid its one cable (pair).
Now with cheaper, smarter, more capable electronics what is to stop us moving the “smarts” that for so long have been intergrated with the controller, on to the solonoid itself, you could then program it over the cloud, a RTC would allow it to turn on/off on a schedule, a hard link to a moisture sensor could allow it to turn on if the soil gets to dry, and cloud computing, or a local weather station could stop it watering if it has rained or is predicted to rain within the next allocated period, say 6 hours.
That gives you more smarts than are most old control boards are capable of, almost as much as modern ones are capable of.
But what if, now we have this connected to the cloud, and we can group them, in one or more groups to control when things are watered. Got tomatos that need watering twice a day but are at opposite ends of the garden, not a problem just create a group of two or more solonoids to control, put in the times and off you go, what about 3 areas, just at another solonoid, 4 areas so on and so forth.
But we are talking the cloud here…. it’s all seeing, all knowing. You could in theory not only control based upon groups, but what about plant types, if you could TELL the system that you were growing tomato’s and you could tell it how much water you want to give them, and when. If you wanted to you could even attach a flow meter to measure the amount of water delivered rather than base it on the arbitary value of time where the pressure and therefore amount of water could vary, with a flow meter you KNOW how much as been delivered.
What I am thinking is a bit light your LifX bulbs, but for solonoids. What about data, well that is easy you can do it through standard 802.11 Wireless, or how about XBEE back to a controller station, or even use a three cable wire to tap in to, using an addressing system such as I2C. In the end it does not matter so much about the how it works technically, so long as I can walk up, plug in the power (or power & data) and connect to the water piping, program it how I want and boom, it works.
Ah well we can all dream