You are a soldier heading into an unknown, potentially hostile town. Snipers could be concealed on rooftops or hidden in a maze of alleyways. You have aerial maps of the area but how do you know what’s happening right now and how do you avoid a brush with disaster?

Simple. Pull out the collapsible autonomous flying device from your backpack and send it out to survey the scene – guided by its GPS locator – transmit images back to your handheld computer and use its “brain” to identify and flag up possible threats.

This is the vision of Swarm Systems, one of the finalists in the Ministry of Defence (MoD) Grand Challenge, a competition to develop autonomous vehicles capable of searching an area without the need to put soldiers’ lives at risk.

The move has been spurred on by the experiences of British troops engaged in Iraq and Afghanistan, who have had to adapt to complicated urban warfare where the enemy operates alone or in small groups.

“This competition is about giving a soldier a sort of sixth sense to know what is around that corner,” says Lord Drayson, minister for defence procurement, “because often we are asking people to patrol in areas where the enemy is among the civilian population. It’s not like 30 or 40 years ago where you’ve got soldiers wearing uniforms who are easy to identify. ”

The British Army already operates remote-controlled planes, among them the Hermes 450, which can be used for reconnaissance missions and fly unmanned for about 20 hours. But with a wingspan of 34ft it is too large for close surveillance and requires a pilot to guide it at all times.

Some of the vehicles being developed as part of the Grand Challenge will be designed to be operated without any intervention from a pilot or driver. According to Drayson, some of the technology could be deployed as early as 2010.

“We could envisage something much smaller than the current remote-controlled planes, something about the size of a small bird, say, which could have sensors on it and be carried by a single soldier.

“This is not blue sky thinking, this is about getting scientists to come up with solutions which we can get into the field as quickly as possible.”

Fourteen finalists have now been selected from 23 initial entries, of which six have been awarded MoD funding of tens of thousands of pounds each. The teams, comprising mainly small businesses and academics, are now developing their devices before they are put to the test next summer at Copehill Down, a model village that is part of the army training facility on Salisbury Plain.

The winner will potentially receive a research grant that could run into millions of pounds to take their invention through to the front line.

The designs are groundbreaking because for the first time they hint at the possibility of removing humans from the loop. Swarm Systems, based in London, is one of the six funded entries. It is developing a fleet of fully autonomous quadrotor “micro air vehicles” (MAVs), which could be unleashed in a swarm and be programmed to identify potential threats using image-recognition software.

The battery-powered quadrotors, dubbed Owls and about the size of a dinner plate, have four small propellers rather than one, dispensing with the need for a tail and tail fan to add balance, and allowing them to be much smaller. Each one would weigh just over 1lb.

“They will be foldable,” says Stephen Crampton, who is leading the Swarm bid. “You will be able to reach over your shoulder into your backpack, pull one out, throw it into the air and off it goes – at least that’s the ultimate aim.”

Once the MAVs are dispatched they guide themselves with the help of GPS coordinates, and use ultrasound and optical flow sensors to navigate around obstacles while radioing back information to a computer. “Basically they can be trained to spot the difference between a picture with a soldier in it, for example, and one without and send an alert,” says Crampton.

Stellar Systems, another of the six MoD-funded teams, is working on a combination of an unmanned ground vehicle and two autonomous, self-flying planes, one low-flying and with a wingspan of just 20in, which would be sent in after a larger, higher-flying plane had identified an area for closer observation.

The Silicon Valley team, a consortium including Kingston and Reading Universities, is planning a semi-autonomous surveillance vehicle, about the size of a wheelbarrow with a camera on top. This could be programmed to follow a set route, with soldiers able to intervene remotely and redirect it away from obstacles or towards a potential area of interest.

The vehicle, dubbed the “moon buggy”, could then unleash a series of tethered “sentinel” balloons or tiny drones containing 360-degree cameras and other sensors, to get a closer look at a potential threat and then radio back information to base.

The United States has so far led developments in the field of autonomous vehicles and the Pentagon predicts that such devices will be a major fighting force in the American military in less than a decade. It already deploys the MQ-9 Reaper, a remote-controlled aircraft described by the US air force as “an unmanned hunter/killer weapon system” with a 66ft wingspan. But as the move towards increasingly autonomous vehicles gathers pace some are warning of ethical dilemmas.

“Autonomous devices are on their way but you’ll always need a human in the loop,” says Christopher Foss, editor of Jane’s Armour and Artillery. “When you’re dealing with quick-moving, close-quarter fighting and having to make very complicated judgment calls, I don’t think a robot could ever take over.”

Frontline life-savers

The Silicon Valley team has produced a self-driving buggy that could have a cargo of micro-drones or tethered “sentinel” balloons loaded with 360-degree cameras and a range of sensors, to give troops the intelligence they need without putting soldiers’ lives at risk The Stellar Systems team is developing a self-driving land vehicle and two autonomous planes. The larger plane would be used for an initial recce, before the smaller one, with a wingspan of just 20in, would be sent in to get a closer picture of potential danger zones

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