This article from Gizmag talks about VR Shoe that will be presented at Siggraph :

“the Powered Shoes effectively cancel the horizontal displacement of the user as they are driven from electrical motors in a backpack worn by the user, enabling omni-directional walking while maintaining the wearer’s position. (…) developed by Hiroshi Tomioka and Hiroaki Yano at the University of Tsukuba in Japan.”