Nao intelligent robot can charge the battery by itself

Nao Energy STation
NEST (Nao Energy STation) is the name for a battery charger. When Nao audit internal system, then found that the battery was weak, it will turn back into the charger by turning the back and move the body to make the electrode made of magnetic to be connected the charger slot at the back of Nao, then it will move wiring harness that is attached platform to sit and wait until the battery is full.

Nao after charging the battery fully, then it will rise up and then move the hand back to rake the charger's pole away from the body, the spring inside of charger will roll the cord and battery charger connector to the original. The highlight of Nao in addition to precise body movements, then it also has the image tracking technology as well. Nao can see the position of the symbol on the floor of charger to calculate the distance for themselves, while they can also remember positions for use in the future even without a visible symbol to calculate the distance.