Smart home requires smart technologies

For the last decade, the philosophy of home automation systems” or “smart home systems” has changed dramatically. From 1998 – 2002 home automation was visualized as a centralized system, where a single computer monitored and controlled all home utilities and appliances. Each device or sensor would be wired to this main computer. This system would feature several different applications, which worked separately, such as:
• Smart house lightening
• Air conditioner, fridge and freezer
• Home alarm/guard system
• Phone and fax communication
• Multi room audio/video system
But these systems have proved to be expensive and not easy to install. Over the last 3 years there have been several great technical implementations, which have led to a transformation of this philosophy:
• Bluetooth low energy wireless technology a recently-released version of the Bluetooth wireless technology aimed at new applications for wireless devices. This Bluetooth specification enables the support of a wide range of applications and smaller form factor devices by offering very low battery usage.
• Mobile broadband 3G/3.5G – 3.5G, 3G+ or turbo 3Gallows networks are based on UMTS and feature higher data transfer speeds and capacity. Current HSDPA deployments support down-link speeds of 1.8, 3.6, 7.2 and 14.0Mbit/s. Further speed increases are available with HSPA+, which provides speeds of up to 42Mbit/s.
• Flash memory – no power is needed to maintain the information stored in the chip. In addition, flash memory offers fast read access times and better kinetic shock resistance.
• Social networks such as Twitter –a free social networking and micro blogging service that enables its users to send and read 140 character messages known as tweets.

A new approach
These new technologies have enabled home automation systems to have a new structure:
Different types of sensors/data loggers feature built-in microcontrollers, flash memory and Bluetooth transmitters. These devices can be set-up locally or remotely. The data log file is stored in local flash memory and can be read locally using PDA or a mobile phone. Data can also be sent to a PC through an Internet gateway, or even tweeted to a social network.
Users will also be able to interact remotely with the network to set up home appliances, such as lighting, an alarm system or heating.

There are three main element switch need further development:
• a universal data transfer protocol which is encapsulated in the Bluetooth core data stream to secure transmitted logged data. This protocol should also give the option to communicate with Bluetooth devices directly without a central PC.
• a simple programming language for the setting up of equipment. Examples of this are a string command to be sent from a Telnet session and its pictogram analogue to be setup through a graphics interface via PC.
• server-based WEB resources accessible through a PC or mobile phone.
The table below shows a possible graphics realization of a “home automation” WEB page and possible “tweet” examples:
A possible example of a log file on Twitter: temperature is 19°
Celsius and the entrance door was opened at 16:44
Receiving log on 18:05:10:02:10
Temp1 == 19
Door 1 == alarm ON3 on 16:44:09:02:10
Of course, these communication sessions must be protected from unauthorized sessions. If there is no internet access, then users can download “reports” from each sensor/data logger locally or from a central PC. Most of this hardware is obtainable now; all users need is WEB developers or an electronics components manufacturer to agree to a universal protocol, and to offer WEB and WAP-based applications.

The article has been provided by Farnell. For more information visit Farnell website at www.farnell.com/bg or the electronic design engineers community www.element14.com.