It’s amazing what you can do with just a few components: a load cell, a high gain analog-to-digtal converter and a NodeMCU module. You can for instance measure the water consumption of your dear plants. If you combine the previous mentioned components with a OLED display you can even visualize the current water level in the plant pot. And if the level reaches a critical low you can have it send an alarm message to your cellphone. Now connect everything and give it a name: Thirsdee is born!
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| Thirsdee showing the current amount of water stored in the pot and the plant. |
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| Thirsdee’s complete setup from left to right: XIAOMI 10400mAh Power Back, OLED display, HX711 ADC, NodeMCU V1.0, Load Cell with Acryl plates and of course: the plant |
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| Oh no! Thirsdee is out Water… |
One problem is the calibration. How do you know how what the “full” weight of the plant plus pot is, how about the empty wait. Of course, you could wait until the plant turns to dust but then it might be too late to water it;-).
Update: 3D printed casing arrived!
Read more about the casing here…
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Hi,
I see you use a Xiaomi Battery Pack for this project, how can you manage that ? I have try with exactly the same Battery Pack, and the consumption was that small that the battery just stop after few seconds.
Hi Phantase. I didn't have such problems. Do I understand correctly, that the battery pack thinks that there is no consumer and goes to sleep? Where did you buy the battery pack? There are some rip-offs around. See http://blog.banggood.com/fake-busting-the-xiaomi-powerbank-30354.html?p=0P21061109440201501M on how to identify them…
Beyond that I have no clue what might be wrong in your setup…
That's it, the battery goes sleep due to low consumption. These batteries have an auto shut down to avoid your mobile overheat.
I have bought my batteries (two of them) on banggood, just by security, I have check on mi.com their serial and they are legit.
I have check the setup with a nodemcu v0.9 and a nodemcu v1.0, that's the same, with the oled on directly, that's the same. I will make some test with some 'active loop' to raise the consumption of the system (just to know when the battery considers it's too low).
Hi Dani, nice project. What I was wondering is whether the weight gain of the plant isn't disturbing the water measurement too much. Or does the plant grow so slowly compared to water usage/evaporation that this isn't significant?
Do you have any picture how the HX711 is connected to the NodeMCU? I have the OLED working, but not the load cell.
Lars.. Did you get that picture
Lars.. Did you get that picture