This week's video was brought to our attention by a post on the DPRG mailing list. The video shows a 2006 Japanese research robot called Roller-Walker, developed at the Hirose-Fukushima Robotics Lab. The robot has a hybrid locomotion system with legs that end in wheels. The wheels can be rotated so that the hubs face the ground and they act as feet for walking. The wheels can also rotate to act as normal wheels, allowing the robot to roll like a roller skater when the legs move appropriately. The result is remarkably graceful.