Accéder au contenu principal

Articles

Affichage des articles du 2016

Low cost low power room sensor with atmega328p and 433mhz transmission

Following my first build of an external garden sensor, here is a simplified version with temperature, humidity and battery voltage measurement for a baby bedroom

[EDIT] feedback about the expected battery duration here

The requirements are:
cheaplong battery life, the atmega328p run at 8mhz with minimal components and functionsunder 8€wireless (433Mhz) with good range (2 walls to cross and 10 meters)Here is the final view attached to a lion for decoration:






And a report from OpenHab displaying the sensor data:



If you want more details about energy power consumption the first article on this subject is more detailled.

Now let's see how to build this.
Bill of materialThe sensors is based on atmega328p(3€),  a 433 Mhz transmitter (1,5€) ,a DHT22 temperature and humidity sensor (4€),a 433 mhz antenna (0,18€)DIP socket adaptor for the ATmega (1€)an electronic prototype printed circuit board (0,5€)At total we are around 8€
PrincipleEvery hour the sensor send the data to a 433Mhz gateway so as to …

Infrared IR, 433mhz and MQTT on ESP8266 bidirectional gateway 433nIRtoMQTTto433nIR

Following discussions on the home assistant forum people gave me the idea to add Infrared communication to the 433mhz gateway. 

The goal is to act as a gateway between 433Mhz sensors, infrared remote controls and a MQTT broker or between the MQTT broker and 433Mhz actuators, infrared devices, It enables to:
receive MQTT data from a topic and send RF 433Mhz signal corresponding to the received MQTT data publish MQTT data to a different topic related to received 433Mhz signal receive MQTT data from a topic and send infrared signal corresponding to the received MQTT data publish MQTT data to a different topic related to received infrared signal 
It can be an interesting part in an home automation system so as to interface sensors and actuators (wall sockets), your tv, home cinema, hifi ... with software like openhab or home assistant.

List of compatible RF sensors here

[EDIT] all infos are now centralized into the github repository take a look at it you will find up to date info about OpenMQT…

Interfacing the 433mhz bidirectional MQTT Gateway with Openhab

In this article I’m going to detail how to integrate the OpenMQTTGateway with OpenHAB using MQTT protocol.
We will explore two kind of integration : -a cheap socket wall switch (on/off) -a voltage sensor ( values between 0 to 5000mV) based on this tutorial
Before continuing you must have :·An MQTT broker running (for example mosquitto) ·An OpenHAB instance running with the MQTT addon binding configured to talk to your MQTT broker ·The 433mhz Gateway setup (either arduino or esp8266 one)
Cheap wall socketThe wall socket that we will be using are these ones
Be carefull not all the wall sockets are compatible with RCSwitch (Library used by the 433Mhz Gateway). For example blyss ones are not compatible.
Learning the codes of your plugFirst step will be to learn the code that are used by the plug. So as to that open your command line and subscribe to the following subject : home/433toMQTT Press the ON button of the remote control of your plug You should see a value on the command line (example 678720)…

433toMQTTto433 - Bidirectional ESP8266 NodeMCU gateway between RF 433Mhz signal and MQTT

The goal  is to act as a gateway between 433Mhz sensors and a MQTT broker or between the MQTT broker and 433Mhz actuators, It enables to:
receive MQTT data from a topic and send RF 433Mhz signal corresponding to the received MQTT data publish MQTT data to a different topic related to received 433Mhz signal 
It can be an interesting part in an home automation system so as to interface sensors and actuators (wall sockets) with software like openhab.

List of compatible sensors here

The interest of putting this gateway to an ESP8266 and not on a raspberry pi is to be able to manage security actions at gateway level (power on a siren, cut power to certain devices) following RF data received by sensors without being dependent to the PI for security related actions.

[EDIT] all infos are now centralized into the github repository take a look at it you will find up to date info about OpenMQTTGateway

You need:

Software:

MosquittoArduino IDE latest version (tested ok with 1.6.10)esp8266 board added to t…

Garage door sensor with Arduino nano

I needed to have a way to know the state of my garage door. 

Several solutions where at my disposal so as to do that;
hack the existing control central to be able to know the position of the door and send the status wireless to my 433Mhz to MQTT gatewayadd an external sensor and send the status wireless to my 433Mhz to MQTT gatewayOne of these two options with a cableAfter some investigations on the control central of my garage door I have deducted that there is no "closed" "open" contact, indeed the stop of the motor seems to be detected by the fact that it is "forcing" maybe by detecting some over current. The sensor that I have at the bottom of this garage door is in case there is an obstacle in the course of the door. Sending a stop to the motor. Unfortunately I can't use this due to the fact it is not actionned at the end of the course.


Safety sensor of the garage door (cannot be hacked for state recognition)

I had to choose solution 2 and build an ex…

Low cost, low power 6uA garden 433Mhz sensor with temperature, humidity ,hygrometer and voltage

I have built an external sensor so as to monitor temperature, air humidity, soil humidity of my garden and the battery voltage. The requirements was:
waterprooflong battery life, the atmega328p run at 8mhz with minimal components and functionsunder 10€wireless (433Mhz) with good range (2 walls to cross and 10 meters)Here is the final view:

And some reports from OpenHab displaying the sensor data:
Air humidity
Soil humidity
Air temperature
We can of course imagine to use these values to control a water pump. Now let's see hpw to build this.

Bill of materialThe sensors is based on atmega328p(3€),  a 433 Mhz transmitter (1,5€) ,a DHT11(1€) or a DHT22 temperature and humidity sensor,a soil moisture sensor (1,6€),an electrical box (1€) a 433 mhz antenna (0,18€)DIP socket adaptor for the ATmega (1€)an electronic prototype printed circuit board (0,5€)a recycled tubeAt total we are around 10€

PrincipleEvery hour the sensor send the data to a 433Mhz gateway so as to be stored in OpenHAB, the data s…

Functions implemented in the home automation system

Here is the functions that can be adressed with the architecture described here, all these functions are integrated and can be linked together if necessary

Alarm systemPresence detection by PIR and door/window sensorsAutomatic detection of house mode (presence/out) by wifi and geolocalisationWhen a presence is detected start a siren and send an emailSmoke detector make the home automation siren start and send an emailCamera motion control (extra added later on)Presence simulationEnergy monitoring Instant consumption monitoringDayly consumption monitoringVoltage measurementHistory charts

MediaSqueezebox integrationPlay/stop change internet radioAdjust volume
Home automationSwitch ON/OFF plugs remotely with an android application or a web siteMonitor temperature and humidity of roomsWeather forecast (integrated from yahoo data)Text to speech, when someone wake up give the weather forecast for exampleHistory charts of temperature and humiditiesIFTTT integration to build scenarios with extra …