Tethering a Human with a Quadruped Robot: A Guide Dog to Help Visually Impaired People

This paper devises a framework to control a quadruped robot tethered to a visually impaired person. The whole-body control of the quadruped robot does not exploit any force sensor. It makes use of two observers: the former for the estimation of the wrench applied on the robot’s centre of mass, which is in turn used to handle the human-robot estimation; the latter for the estimation of the external forces acting on the legs to guarantee a stable balance on irregular terrains. Besides, an admittance filter is employed to guarantee a safe human-robot interaction. A supervisor is designed and placed side by side with the quadruped whole-body control to understand human needs and handle lifelike situations. The validity of the approach is tested in a realistic simulation environment.