Modern day logic and embedded systems are all around us. They are so ubiquitous and their design so efficient, say researchers at the RUNES (Reconfigurable Ubiquitous Networked Embedded Systems) project in Europe, that these miniature self-contained computers could be optimized to create on-the-fly wireless networks and assist in traffic control and even emergencies.
They use the example of a fire in a mountain tunnel. Ordinarily a tunnel full of smoke and fire would be a difficult situation because it would take time to pin down the location of the blaze and where people were trapped.
Wireless sensors, oblivious to smoke and heat, could make sense from chaos and route maps and instructions to firefighters through handheld terminals or helmet-mounted displays. But there's a caveat - because each system would need to be customized, the wireless networks basically have to be able to build themselves.
Creating software capable of forming self-organizing wireless networks across multiple platforms was the task of the RUNES project.
RUNES, led by Ericsson, covered 21 partners in nine countries. They set out to create middleware: software that bridges the gap between the operating systems used by the mobile sensor nodes and high-level applications that make use of data from the sensors.
RUNES middleware is modular so programmers can create applications without knowing much about the detailed working of the network devices supplying the data. This also makes it easy to incorporate new kinds of mobile device, and to re-use applications.
Where office networks use full-size computers with separate routers and human administrators, self-building ad-hoc mobile networks would be low-power devices that can do their own wireless routing and forward signals from other devices that would otherwise be out of radio range.
In addition, the ad-hoc network must be able to assemble itself from whatever devices are nearby and adapt as conditions change or new ones move into range. The network they envision would combine handheld computers, small self-propelled units and sensors built into 'smart' clothing.
Interoperability was a challenge, partly because embedded systems themselves are so varied. At one end of the spectrum are powerful environments, such as Java, while at the other are simple systems designed for wireless sensors. For devices with small memories, RUNES developed middleware modules that can be uploaded, used to carry out specific tasks, and then overwritten.
Project partners also worked on an operating system and a simulator. Contiki is an open-source operating system designed for networked, embedded systems with small amounts of memory. Simics, a simulator allowing large networks to be tested in ways that are impractical with real hardware, is commercially available from project partner Virtutech.
The tunnel fire scenario was valuable in demonstrating what networks of this kind can achieve. Using real sensor nodes, routers, gateways and robots developed during the project, a demonstration setup showed how, for instance, a robot router can manoeuvre itself to cover a gap in the network’s wireless coverage.
“A lot of people have been looking at embedded systems networking, but so far there has been a reluctance to take the plunge commercially,” says Dr. Lesley Hanna, a consultant for RUNES. “RUNES’ open-source model is an excellent way to stimulate progress, and it should generate plenty of consultancy work for the academic partners.”
