Since the posts on 15 February, 16 and 27 March I have completed the LoRa wireless based remote soil moisture meter and deployed it for use in a herb garden outdoors. To conclude and summarise this project, I have brought some of the previously posted information together with its new features in this post.
The remote module with the moisture sensor pushed into the soil transmits the moisture measurement every hour using a LoRa wireless data link. It is battery and solar powered. The moisture meter will not be required all year round. So the solar panel only has to keep the battery sufficiently charged for a few hours of operation each day during the summer. The solar panel is supported by a tablet stand fixed down with 'P' clips.
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| Remote module & solar panel deployed outdoors - notice the antenna |
The LoRa link receiver module, located indoors, receives the measurement value and displays it on its OLED display.
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| Remote module with antenna & sensor - inset top right the receiver module |
If the receiver module is connected to a wifi LAN it can also send the measurement value to a web-page, my dedicated Android app, and additionally publish the RSSI ( received signal strength indication ) and time on an MQTT broker* ( making the data accessible world-wide ! ). If I have my Node-RED local server up and running, the measurement value can also be sent by email, saved to a file, published on the HiveMQ MQTT broker*,
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| The various message types that are published on the MQTT broker* |
and saved to the cloud database of the Ubidots data visualisation platform for presentation.
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| My custom dashboard for presentation of the moisture data on Ubidots |
See the previous posts and some recent Tweets going back to 23rd March for details of MQTT, Node-RED, LoRa, the webpage server & Android app.
* Subscribe to the topics SpacerLabs/Status, SpacerLabs/Moisture & SpacerLabs/Moisture1
