The Bear is highly manoeuvrable

The Battlefield Extraction Assist Robot (BEAR) can scoop up even the heaviest of casualties and transport them over long distances over rough terrain.

New Scientist magazine reports that the "friendly appearance" of the robot is designed to put the wounded at ease.

It is expected to be ready for testing within five years.

While it is important to get medical attention for injured soldiers as soon as possible, it is often difficult and dangerous for their comrades to reach them and carry them back.

The 6ft tall Bear can cross bumpy ground without toppling thanks to a combination of gyroscopes and computer controlled motors to maintain balance.

BEAR FACTS 1. Teddy bear face designed to be reassuring 2. Hydraulic upper body carries up to 227kgs (500lbs) 3. When kneeling tracked "legs" travel over rubble. Switches to wheels on smooth surfaces 4. Dynamic Balance Behaviour (DBB) technology allows the robot to stand and carry loads upright on its ankles, knees or hips for nearly an hour

It is also narrow enough to squeeze through doorways, but can lift 135kg with its hydraulic arms in a single smooth movement, to avoid causing pain to wounded soldiers.

While the existing prototype slides its arms under its burden like a forklift, future versions will be fitted with manoeuvrable hands to gently scoop up casualties.

The Bear is controlled remotely and has cameras and microphones through which an operator sees and hears.

It can even tackle stairs while carrying a human-sized dummy.

Daniel Theobald, the president of Vecna Technologies, which is developing the robot for the US Army, said: "We saw a need for a robot that can essentially go where a human can. The robot will be an integral part of a military team."

Gary Gilbert, from the US Army's Telemedicine and Advanced Technology Research Centre in Frederick, Maryland, said that the teddy bear appearance was deliberate.

"A really important thing when you're dealing with casualties is trying to maintain that human touch."

Vecna is working on other potential applications for the robot technology - including helping move heavy patients in hospital.