I want to show you an irrigation controller and moisture sensor project I have been working on and am planning on manufacturing for SmartThings.
When I got SmartThings I was looking for an irrigation controller to hook up to it. I couldn’t find one that did what I wanted, at least, not easily. I wanted to be able to have it change it’s schedule based off some kind of moisture sensors and use the weather forecast. I also wanted it to spray some neighborhood pets that were making a mess of my mulch beds.
**So I built Spruce. **
Spruce uses a Zigbee radio to connect to SmartThings and then a series of apps depending on what it needs to do. It is 8 zone with touch buttons and LED status for each. The Spruce logo in the center changes color to indicate connection. It uses the same standard 24vac power supply just like every other irrigation timer.
We also have a Zigbee moisture sensor, the Spruce Sensor. The moisture reading uses capacitance so there are no electrodes to corrode.
Since Spruce pairs directly with SmartThings and uses the Switch Zigbee cluster it is easy to write apps to utilize the Spruce moisture sensors and the weather API. One smartapp has straight forward manual scheduling that is set up for zones without moisture sensors. And another smartapp uses moisture levels and weather to decide when and for how long to water. With the Switch command, the built in SmartThings motion triggers work to switch on a zone to scare off unsuspecting pets digging around in the yard.
**With the flexibility of SmartThings and all the sensors and external triggers available, the options are pretty limitless. **
At my house I have been running 5 zones off of it without issue for 2 months now, although I have recently started updating the code to become fully Zigbee HA compatible. There is still some testing to go, but joining, fingerprinting, device identification are all fully functional and SmartThings installs the device without issue. I still have an issue with the “st cmd” and have been using a workaround.
I have also been experimenting with moisture sensor control and several different feedback loops to see which method generates the best watering schedules. The water needs are based off published papers. The whole system is getting installed at 2 people’s homes this weekend, so we will have some more data points for functionality and moisture control loops. I have to say, running with moisture feedback and weather forecasts is pretty cool!
Its pretty neat to see the notifications that Spruce is rescheduling because Zone 2 moisture is 75% or Spruce is rescheduling because of 80% chance of rain! SmartThings is awesome!
A long story, short, partway through testing, I though this would be cool to manufacture. So I went through a few iterations of PCB boards and built some prototypes.
I still have a few things to work out from a manufacturing and Zigbee HA compatibility viewpoint but it is almost there. The IC uses the Arduino Leonardo bootloader with USB so it is hackable. There is a touch IC and LED driver onboard as well as AC to 3.3v power chip. The prototypes shown are 3D printed but will be injection molded in the future.
6/15/15: We have successfully funded our Kickstarter, pricing was very competitive with other devices out there, beating most by a healthy margin when you already own SmartThings. We’re also now taking preorders on our website.
What are your thoughts?