The aim is to carry out conversation experiments between humans and robots in space, speaking with Japanese astronaut KoichiWakata in his native tongue.
Endeavour has brought home Japanese astronaut KoichiWakata, who has spent 138 days in space and has been a member of three separate space station crews.
In addition, Endeavour delivered a new long-stay US crew member, Tim Kopra, to the ISS and will bring back Japan's KoichiWakata, who has lived aboard the platform for more than three months.