IoT Cube For Greenhouse

Carrying-on with Climate Cube for Greenhouse project now it is time to put things online. I suggest check above link for details before you read further.

Let's scope out the place where IoT Cube needed.

As you can see the picture above I have three different greenhouses (n° 27, n° 35 and n° 141) each of 2000 square meters (10x200) where three different Climate Cube have been placed. I want all the control units to be connected to the internet through a WiFi network. In this area only 2G/3G network can serv internet so first I had to pick an ISP. First one was a static IP, 3G sim card by Vodafone. Yes, it had static IP address however it had a huge monthly cost considering the data usage which was/is quite low (~20 MB/month). Later I moved to Telekom using a prepaid 4G sim card...

Okay we have the sim to access internet. Now we need a modem...

Let's check a bigger picture before.

The simpler the better is my starting point.

In the future I am going to monitor as many 'variables' during production as possible. You can think of variables like:

• Air/soil temperatures along the 200 meters structures

• Air humidity above the plants and between the plants

• Soil/leaf wettness

• Irradiation

• Outer temperature/humidity

• Temperature of the geothermal water/heating

• Water pressure through the main irrigation line

• CO2 (eCO2) level in the air

• etc.

Using single GSM/GPRS modems to upload each of the above data given from the three different production areas is not possible (or has an insanely huge cost). Considering cost efficiency (and the first thought) I decided to built a wifi network so later It will be more flexible to connect any kind of MCUs to internet. Okay now I (only) have to pick a wireless router which accepts 3G (USB) modems.

In the beginning I tried several brands/models of routers (Tp-link, D-link "Any"-link) but finally i found very good combo of USB 3G modem and Wifi router:

It is the Huawei E3531 3G USB modem + ASUS RT-N18U router. They got the longest term of stability what I experienced (months of uninterrupted ON time).

Let's skip ahead.

We've got the hardware. If you check the picture you can see where is the location i put the IoT Cube Base. The router itself has 3 external antennas but 1 have been changed to a TL-ANT2415D. With this mod I was able to expand radius with another 25 meters. Later if more 'things' will be attached to the network I am going to put new routers set as signal repeaters but now it is just enough with this single router.

And of course for the wifi router a plastic box have been used :)

Now (and in the thingspeak channel) I measure the temperature of this:

This 30 cm wide 200 meters long HDPE pipe filled with water acts as buffer for the geothermal water which actually runs accross PE pipe in this HDPE pipe. It would worth another hour to explain how actually we use geothermal water in the 200 meters long structure but maybe later.

Last, but not least under the below link you can find the feed channel of Climate Cube n° 27 and you can check what is being measured

Climate Cube Status Centre - Test for n° 27

As mentioned earlier I am going install many other devices which will measure more details of micro-climate/plants/irrigation etc...And that's what I call:

Sensor Cube for Greenhouse.

So stay tuned more studies on the horizon! :)