We are living in the world of automation where most of the systems are getting automated, such as industrial automation, homes and other business sectors. Home automation systems are advancement to the mechanization processes wherein human efforts are needed with the machinery equipments to operate various loads in homes. It involves automatic controlling of home appliances using different technologies and controllers over desktops, laptops smart phones or tablets.
What is a Home Automation System?
Home automation system makes the operations of various home appliances more convenient and saves energy. With the energy saving concept, home automation or building automation makes life very simple nowadays. It involves automatic controlling of all electrical or electronic devices in homes or even remotely through wireless communication. Centralized control of lighting equipments, air conditioning and heating, audio/video systems, security systems, kitchen appliances and all other equipments used in home systems is possible with this system.
This system is mainly implemented by sensors, controlling devices and actuators as shown in the figure. The sensors detects light, motion, temperature and other sensing elements, and then send that data to the main controlling devices. These sensors can be thermocouples or thermistors, photo detectors, level sensors, pressure sensors, current transformers, IR sensors, etc., which need an additional signal conditioning equipment to communicate with the main controller.
Controllers may be personal computers/laptops, touch pads, smart phones, etc., attached to the controlling devices like programmable-logic controllers that receive the information from the sensors, and based on the program, control the actuators. This program can be modified based on the load operations. The programmable controller allows to connect various sensors and actuators through various input and output modules whether they are analog or digital.
Actuators are the final controlling devices like limit switches, relays, motors and other controlling mechanisms which finally control the home equipments. Communication plays an important role in this home automation system for the remote access of these operations. This smart home system also provides continuous monitoring through video surveillance with cameras, scheduling, and energy saving operations. This is the best solution even for the elderly and the disabled persons to operate equipments.
Types of Home Automation Systems
Implementation of the home automation depends on the type of controls like wired or wireless. There are mainly three types of home automation systems:
- Power line Based Home Automation
- Wired or BUS Cable Home Automation
- Wireless Home Automation
1. Power Line Home Automation System
This automation is inexpensive and doesn’t require additional cables to transfer the information, but uses existing power lines to transfer the data. However, this system involves a large complexity and necessitates additional converter circuits and devices.
2. Wired Home Automation System
In this type of automation, all the home equipments are connected to a main controller (programmable logic controller) through a communication cable. The equipment is attached with actuators to communicate with the main controller. The entire operations are centralized by the computer that continuously communicates with the main controller.
3. Wireless Home Automation
This is the expansion and advancement of wired automation which uses wireless technologies like IR, Zigbee, Wi-Fi, GSM, Bluetooth, etc., for achieving remote operation. As an example, the GSM based home automation provides the controlling of home equipments by an SMS to the GSM modem.
As a practical example, the following home automation system project, in which loads are controlled by a touch panel, is very informative.
Touch Screen Based Home Automation System
This touch-screen based home automation project explains how the automation can be implemented to our homes at lower costs. In this system, a microcontroller is attached to the light loads to control them. At the controlling side, a touch screen allows any user to send the command signals in order to operate the loads. These signals are transferred to the microcontroller, and according to the program written, it sends the command signals to the encoder circuit. Encoder converts this data into binary format, and then transfers that to an RF transmitter; from there the data is transmitted to the receiver section.
At the receiver side, the RF receiver receives the information sent by the transmitter section, and then decodes and transfers that to the microcontroller. Therefore, the microcontroller sends the command signals to an opto-isolator, which triggers the TRAICs. All the light loads are controlled by the TRIACs; as switches these are enabled only after triggering their gates.
It is therefore possible to implement home automation using GSM as extension to the above project by simply adding a GSM modem to the receiver side of the microcontroller in place of an RF receiver. Therefore, the message send from a cell phone is received by this modem, which then sends that control signals to the microcontroller, which further controls the loads.
This is all about the home automation systems with a practical example. In addition to this, it is also possible to build the best home automation system using advanced controllers like PLCs. We hope that you might have received very informative and insightful knowledge from this article. We appreciate your valuable time that you have spent reading this article completely and therefore anticipate your feedback, suggestions and comments in the comment section below.