SupraPeds: Humanoid contact-supported locomotion for 3D unstructured environments

Maintaining humanoid robot stability in unstructured environments is nontrivial because robots lack humanlike tactile sensing and require complex task-specific controllers to integrate information from multiple sensors. To deploy humanoid robots in cluttered and unstructured environments such as disaster sites, it is necessary to develop advanced techniques in both locomotion and control. This paper proposes to incorporate a pair of actuated smart staffs with vision and force sensing that transforms biped humanoids into tripeds or quadrupeds or more generally, SupraPeds. The concept of SuprePeds not only improves the stability of humanoid robots while traversing rough terrain but also retains the manipulation capabilities. In order to control the potentially numerous contact forces on SupraPeds, we develop a friction-consistent whole-body control framework that implements generic multi-contact control for arbitrary humanoids, which enables autonomous balancing while complying with friction constraints. The simulation results are presented to demonstrate that the proposed control framework can efficiently deal with multi-contact locomotion in 3D unstructured environments.