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Robot pack horse and other drones unveiled at US show

10 August 2012 Last updated at 07:49 BST

Robotic pack horses that can follow soldiers over any terrain have been showcased at an exhibition in Las Vegas.

Unmanned robots - or drones - are already used by the military, but the technology is becoming big business due to growing interest from commercial companies.

The BBC's Alastair Leithead reports on the devices of the future.