The world's first robot marathon is under way in western Japan, with five two-legged participants racing on an indoor track.
The race kicked off today with the 12in tall, battery-charged robots competing around a 110-yard race track.
They will have to cover 26 miles.
Japanese robot maker and event organiser Vstone said the Robo Mara Full race in Osaka will demonstrate the machines' durability and manoeuvrability.
Vstone robots took an early lead, while two entrants by Osaka University of Engineering teams got off to a shaky start. The race is expected to last until Sunday.
Vstone chief executive Nobuo Yamato hopes the event will become international in the future.