This chapter is from the book
This chapter is from the book
This chapter is from the book
Automation Processes are Trigged by an Event
Events that are common and vital to home automation process include these:
- Elapsed Time
- Arrived Time
- Occurring and Recurring Events
- Temperature Changes
- Voice Commands
Proximity Sensing:
- Motion Sensor
- Heat Sensor
- Incoming Information Processing
- Outgoing Information Processing
After that the processes or pseudo-processes must be known and stored in the database for human like or referred control to occur from actions to be taken by the automation platform.
The object of control must have a name or an ID such as “Bedroom Lamp” that not only acts as a label for the process but also identifies the device or appliance being controlled. That name is then attached to the device name that is identified by the control interface within the protocol such as house and unit ID in X10.
The desired conditions or desired outcome of the automation process must be known and stored in the automation setup’s database. One example would be that the desired new condition is to dim the lamp to a preset variable.
Any variable condition must be articulated and defined in the database, such as dim the lamp to 33 percent of total possible brightness.
A trigger or stimulus to set off the automation process is defined. This could be the ringing of the doorbell or the arrival of a clock time.
A human stimulus or automated sensor or predefined action then presses the predefined and stored steps into action through the controller sending out signals in various protocols to the devices that will be acted on.
Process Actions
When the control stimulus occurs, the automation process goes through these primary action steps:
- Finds the named object device in the database.
- Finds or collects the desired state or predefined condition.
- Converts the device name to a recognized protocol name in the physical layer address scheme being used (example: X10).
- Combines the object’s physical-layer address with the control parameters.
- Sends the control signal and parameters over a serial port or USB port, or to another type of control interface. It can also use the computer’s own communications bus to convey commands such as playing music over the sound card.
- The interface module converts the control signal into a physical layer message and sends it out on the wire (or RF) at the appropriate time.
- The physical media (house wiring or wireless or infrared) carries the control signal over the media to the connected devices.
- The target device receives the control signal and the device or module sets the new condition called for in the message and creates the new state or condition of the object of control.
- The control device in two-way protocols sends back feedback if the device is capable and feedback is needed, warranted, or requested by the controller.
In later project chapters you will see examples of this process in the setup phase and at work when you follow the examples for your own projects. The control framework pieces for each technology are well defined, and all you have to do is drop your control identities, types, and unique naming information into the framework.
There is a lot more to learn about the protocols mentioned in this chapter, but luckily, for those looking to implement a home automation system, you can use these products successfully without knowing any additional information. To be successful with your project, be it your own project or a project that follows the examples in this book, you only have to keep track of some details and load them in the setup screens and application windows. Later chapters show in detail how these setups are handled. The HAL software is designed to make it as easy as possible on you, the end user, to successfully set up your system. If you can keep track of details and make accurate entries in the HAL setup screens, you can harness the power of these protocols to control any controllable object in your home.
See the author’s website www.homeautomationmadeeasy.info to find sources of additional information about protocols and process information.