20 June 2012 Last updated at 17:05

Robot lifeguard helps rescue swimmers

A Robot lifeguard is being used to rescue swimmers at a beach in the US.

The remote controlled device, nicknamed Emily, travels at up to 30 miles per hour and can rescue up to six people at a time.

It's kitted out with sonar sensors to detect movement in the water and is twelve times quicker than a normal lifeguard.

Emily's controlled back on dry land and finds people in trouble before driving them back to safety.

On board cameras and speakers mean the human lifeguards can keep in touch with the victim.

Emily can even be dropped from a helicopter to help with more complicated rescue missions.

It's been on trail at a beach in California in the US and if it goes well we could be seeing lots more water robots.