The collar which visualises your dog's emotions

A collar which changes colour depending on your dog's mood has been developed by a biologist in Japan.

The Inupathy collar monitors the animal's heart rhythms and displays whether they are calm, excited, happy or concentrating. It can also be used by owners to hear beyond the barks and learn how to manage stressful environments.

The device's co-creator, Joji Yamaguchi, says he invented the device because he wanted to gain a better understanding of his dog's emotions.

BBC Click's Spencer Kelly finds out more.

More at BBC.com/Click and @BBCClick.