From the video its hard to tell what technology is behind this robot but heres the Google translation of the press release:

Communication robots for the elderly

"Nodding Kabochan SMILE SUPPLEMENT ROBOT"

Launched mid-November!

Pumpkin is not nodding, communication robots for the elderly in the shape of a little boy.

The reaction of five sensors that are built, or nodding,

He makes a variety of chat depending on the season.

To take advantage of robot technology, the elderly, who also receive care, How to care for, and further engaged in the business who care, safe delivery and a smile will help to improve life.