'Big Dog' will lighten soldiers' load

US marines have tried out a Google-owned robot named "Big Dog" in its first live military trial in Hawaii.

The Legged Squad Support System, or LS3, which is being developed as a robotic mule to carry the load of soldiers in the field, was put through its paces last weekend at the annual Rim of the Pacific military drill.

It is hoped the futuristic robot, which can run for 35km without refuelling, can reduce the amount of equipment that fighters have to carry, which can be up to 50kg.

Big Dog was created by the robotics firm Boston Dynamics, bought by Google, and has been in development for the last three years.

Their aim was to produce a highly mobile, semi-autonomous legged robot that can follow soldiers through rugged terrain.

It has been programmed to interact with troops in an instinctive way, similar to a trained animal and its handler.

A soldier operates the machine by strapping a sensor to his or her foot and the LS3 then automatically follows him or her using computer vision, so there is no need for a dedicated driver.