Earlier this year we saw both the HOAP-2 and WABIAN do quick turns by sliding on their feet (see here). Now the same principle has been demonstrated with AIST’s HRP-4C, which is able to turn approximately 90 degrees in around one second by swiveling on the ball of its foot. In order to turn in place, bipedal robots often take a number of tiny steps as they rotate their hip joint to reposition their legs, which is slower, less natural, and less efficient than this method. However, if the ground or floor is too rough the swivel method may not work.
[source: AIST Channel @ YouTube]