fHelper - capacitive humidity sensor

Time ago I did use a traditional humidity soil sensor (from the Grove family) for the fHelper project and it ended up very badly.


After some search I decided to try a capacitive sensor.
There are many on the market, so I just did pick up one of the cheapest
and easy to have one, from Amazon.


This is a brief review of this sensor.

fHelper on Node-Red

If using Node-Red to handle fHelper an algorithm to handle the alarm is needed.


Here a brief description of the algorithm implemented in Node-Red.
The server is controlling a LED on the client to notify the plant need to be watered.

Set up a Huzzah32 IoT client - testing

Using an IoT approach for the fHelper can helps to evaluate the measurements done more easily, using the MQTT protocol.

We need a server capable to receive the measurements from the fHelper sensor (client) and eventually work on the received data.
And of course we need a client/sensor capable to send the humidity level to the server.

See the article about the MQTT/Node-Red server about the preparation of an IoT server on a Raspberry Pi.
This article is about how to quick set up an IoT client for fHelper in order to run some feasibility tests on the sensor and its response.
Basically the idea is to evaluate if the system is reliable enough for the purpose.

Set up a Raspberry IoT server

For some projects can be useful to have a place and mean where to collect and store data retrieved form some process.
IoT 101.


There are many IoT services out there, many free, but for some applications is better to have everything close.
Let set up a small and efficient IoT local server based on MQTT protocol running over a Raspberry Pi.

Happy Pi Day

Well, just a Happy Pi Day to everybody who care :)

Stay tuned for articles with the glorious Pi in the near future.

Huzzah32 - start to play with

Huzzah32

Adafruit has many nice platforms to start to create embedded devices.
This article would help to start to play with this platform.


One of them is called Huzzah32, member of the Feather family.
The Huzzah32 is based on a dual-core ESP32 chip, 4 MB of SPI Flash, and tuned antenna since it has both WiFi and Bluetooth Classic/LE support plus some GPIO ports, I2C and SPI capabilities.