A team of robot footballers is training for the RoboCup, an annual football competition for non-humans.

The robots from the University of Hertfordshire came second in the 2014 contest, held in Brazil.

The competition was set up in 1997 to encourage advances in robot intelligence.

Around 500 teams from more than 45 countries will take part in this year's contest, which kicks off in China on 19 July.

BBC technology reporter Jane Wakefield went to see the robots in training.