Besides the contacts between the feet and the ground, in some cases motion of humanoids may require additional contacts with environment. When spatial distribution of contacts is needed in order to perform planned motion, decision where the next contact will be established may be of fundamental importance. To ensure that planned motion will be feasible and dynamically balanced, all contacts wit...

We present a rollover prevention control law for wheeled mobile manipulators based on the invariance control framework, and that makes use of recursively calculated analytic gradients of the mobile manipulator’s zero moment point. Our controller relaxes many of the assumptions made in existing approaches, and enhances robustness through the use of exact gradient information. Numerical experimen...

In this paper, we propose a universal biped walking generator that can plan smooth and flexible walking motions in complex environments, including stairs, slopes, and obstacles. In addition to generating collision-free patterns while keeping the balance of the robot, this generator also checks whether the patterns are achievable for the robot. Aiming at this goal, we introduce a simplified walk...

Moving the torso laterally in a walking biped robot can be mechanically more torque-e±cient than not moving the torso according to recent research. Motivated by this observation, a torque-e±cient torso-moving balance control strategy of a walking biped robot subject to a persistent continuous external force is suggested and veri ̄ed in this paper. The torso-moving balance control strategy consis...

The focus of this paper is the problem of foot rotation in biped robots during the single-support phase. Foot rotation is an indication of postural instability, which should be carefully treated in a dynamically stable walk and avoided altogether in a statically stable walk. We introduce the foot-rotation indicator (FRI) point, which is a point on the foot/ground-contact surface where the net g...

2-D projective moment invariants were firstly proposed by Suk and Flusser in [12]. We point out here that there is a useless projective moment invariant which is equivalent to zero in their paper. 3-D projective moment invariants are generated theoretically by investigating the property of signed volume of a tetrahedron. The main part is the selection of permutation invariant cores for multiple...

An adaptive switching controller based on dynamic zero moment point for versatile hip exoskeleton is proposed in this work. The linear finite hysteretic state machine designed to recognize hybrid motion phases. torque planning strategy deployed obtain assistant adaptively under different locomotion. Experiments are carried out verify the performance of controller, confirming stability and accur...