🌱 Off the Clock Design Challenge - Meshfarmer Ubidots dashboard

Meshfarmer Ubidots dashboard

Task from latest blog post was To connect automated node-red flow to the Ubidots again.

Automated node-red flow

As I blogged in the previous post I managed to build an automated node-red flow. During the further steps I found a few issues. For first I found out that mote can send probably only one value in periodical manner. So I customized flow to implement auto-repeat injection nodes which can initiate value measuring process very easily with one-shot command. I can imagine that the mote can be set-up into a mode of multiple measuring but this I like more. It is only node-red dependend and because I decided to base this on node-red, it is fitting into the pocket.

Ubidots for Educational use

Second type of issues were connected with Ubidots. Ubidots itself is a great platform but their Educational accounts have one big disadvantage. The message delivery into the Ubidots device is not guaranteed at all in the Educational mode. It is quite understandable. They need to earn money and to create a free platform with perfect service would disrupt their paid scenarios.

The reason is that not every message sent from the DustNetwork IP Mesh manager arrives into the Ubidots dashboard. But every other or every third propably does 👍.

Here is current Ubidots dashboard for Mesh#farmer:

Current temperature, current battery voltage, uptime and current soil humidity are measured and publicated. Wait...what? Soil humidity? How is it done?

Soil humidity sensor

In order to make the Mesh#farmer usable I implement the Soild humidity sensor as an example of the possibilities. On eBay there is a lot of Soil sensors from China which can be used. I bought one and used it. It's output is lead to the ADC0 mote input. Basically it is only a resistance meter.

Here it is how the sensor looks like:

Forget the fork I only used the comparator/amplifier. It is powered from the 3V3 system voltage but I reduced it into the 1V8 level in order to save power and to limit it's output. Comparator used there LM393 should run from 2,0 V but I am sure it is ok here.

Node-red flow

Here is the modified node-red to Ubidots flow:

🎯 Next step

To finish the mechanical work on the Mesh#farmer and to prepare a video presentation.