Robust estimation of walking robots velocity and tilt using proprioceptive sensors data fusion

Availability of the instantaneous velocity of a legged robot is usually required for its efficient control. However, estimation of velocity only on the basis of robot kinematics has a significant drawback: the robot is not in touch with the ground all the time, or its feet may twist. In this paper we introduce a method for velocity and tilt estimation in a walking robot. This method combines a kinematic model of the supporting leg and readouts from an inertial sensor. It can be used in any terrain, regardless of the robot's body design or the control strategy applied, and it is robust in regard to foot twist. It is also immune to limited foot slide and temporary lack of foot contact.