I would like to tell us about your home automation system to raspberri pi With this system it is very easy to automate your home or apartment.
The project is not fully commercial lined flash microcontrollers and other sources
Its main ideology is distributed principle of construction. In other words, there is a central unit connected to the controller, which in turn connect various sensors and actuators. The advantage of this construction is that it is not necessary to pull the long lines from each sensor to the central unit - just one cable UTP, which is used as a communication line (RS485) and as the main power loop controllers.
Just advantage of a distributed system is its partial operation in the event of failure of any controller or central unit.
In addition to universal controllers, which allow you to connect analog and digital sensors (security, fire, water leakage, temperature) and actuators, and controllers were considered to perform "narrow-profile" function - for example, an eight-meter temperature and humidity. This is to some extent (with respect to this controller) distribution functions are not, but rather their centralization. Therefore, considered here home automation system that best fits the definition of centrally-distributed. This construction principle allows to achieve maximum flexibility. By combining various controllers and its own port GPIO Raspberry Pi can be configured home automation system with all the necessary requirements.
The system consists of the following controllers:
Climate (8-channel temperature controller and humidity). The controller allows you to collect temperature and humidity readings from one sensor DHT22 and seven sensors DHT11. Total system can connect up to 10 of these controllers
Thermostat (four-channel temperature controller). The controller can control up to 4 loads in manual mode and the temperature on the set parameters. Entering temperatures as possible directly on the controller, or remotely through a web-interface. Normal and reverse control type channels allow you to use a controller for controlling the heating and cooling. Total system can connect up to 10 of these controllers
The radio module is used to emulate remote controls and collect information from radio sensors. Total system can connect up to 10 of these controllers GPIO - Output Ports Raspberry Pi. C They help to organize the management of 6 different loads (actuators) Controller 1 (controller with a set of I / O) allows you to control 4 loads (actuators), monitor the status of 4 digital inputs, to collect information on temperature and humidity sensors and DHT11 DHT22. Total system can connect up to 20 of these controllers
Here I show the form of web-interfaces for various controllers. Access to the interface can be accessed via a password from your browser. This allows you to drive home from any location with Internet access
This looks really interesting. Though, I have a couple of questions if you don't mind:
1. how collisions on rs485 are handled?
2. what is the architecture of this bus? Can only master talk to slaves, or a slave can also initiate a connection to the master?
3. did you roll out your own distribution? If not, which one did you adapt?
4. all sensors are powered via UTP: how many sensors and what current can be sinked that way (from your experience)? What are voltage dropout with the last sensor? Is it a problem for you?
5. How do you program your frontend (what s/w stack is used) ?
I've been working for some time on something similar, thus, I'm asking.
Again, lot of work has been put into this project and looks nice.