Texting becomes the big turn on

Tom Shelley reports on a simple way of using mobile phones to start and stop lighting and machinery Members of the press who attended the recent Glastonbury pop festival were given kits that allowed them to make their tents light up remotely so they could find them in the dark. Sending a mobile phone text would cause electroluminescent cords on the corners to light up and an antenna to rise from the top with an orange light on it. The initiating technology, devised by West London based consultancy Design Stream, was remarkably simple. Inside each control box was as rechargeable battery to power the illumination and the antenna actuator plus a relay, some simple electronics and a cut down mobile phone. Actuation occurred when the phone keyboard LEDs were energised on receipt of a text message. Illumination of the screen or initiation of the ring tone were also considered as triggers but illumination of the keyboard LEDs is apparently simplest, most reliable, and delivers the most appropriate electrical output. Arrangements were made with the service provider, Orange in this case, to block off all but text messages of the right type so there were no false initiations from wrong numbers being dialled. Co-directors Charanjit Nandra and Miles Pennington explained that they have a general policy of seeking to make up systems from what is commercially available whenever possible and that it is cheaper and much quicker to purchase cut down complete phones than develop special PCBs to undertake such tasks. Using tried and tested phones also removes an area of possibly unreliability. After the Glastonbury exercise, known as "Text-Me-Home-Dome", the team have developed other ideas for customers, but feel they have only just begun to scratch the surface of the market possibilities. Initiation of outside security lights, garage door opening, starting up home heating systems to pre-warm houses before leaving the office, plus possible industrial applications are all obvious possibilities. Low power radio can be used to perform some of these tasks, but not from a long distance. The equipment shown to Eureka was all based on conventional phones without cases, carefully mounted in machined chassis. A reset system was incorporated to cope with phones 'freezing' or closing down due to flat batteries. The company is now looking for more greatly cut down phones with which to build their systems, and suggests there may be possibilities in re-cycling old phones which can still receive text messages, but no longer have sufficient bells and whistles to please the more sophisticated users. Miles Pennington said, "Perhaps the most useful applications for such a switch are in systems where you can have a two way functionality, where the switch can alert you by sending a message to your phone as well as be triggered by your phone through receiving a message." Design Stream Pointers * The simplest way to make a remotely actuated switch is to base it on a conventional mobile phone. * Initiation by text message, with voice messages blocked off by the service provider eliminates the possibility of erroneous initiations