Decentralized Coordination Mechanism between Neck and Limbs for Efficient Quadrupedal Walking An optional robotic arm unit, like animalsxe2x80x99 neck, allows quadruped robot to achieve multifunctional tasks such as manipulation and patrol. However, increases in body weight due to the neck unit will make energetic issues in legged robotsxe2x80x99 locomotion more serious. This study presents a minimal decentralized coordination mechanism between a neck and limbs, especially focusing on quadruped mammalsxe2x80x99 nodding behaviors for efficient walking. The results of two dimensional (2D) simulation suggest that bilateral sensory feedback mechanism between neck and limbs plays essential roles for the quadruped robot to coordinate neck and limbs in response to the physical situation of the body parts, achieving efficient quadrupedal walking.

Taskoriented Hierarchical Control for a Quadruped Robot This study aims to build a standard framework that can be applied to accomplish different tasks for a quadruped robot. To achieve this goal, a taskoriented hierarchical control framework is proposed. The framework is composed of four layers, including the task, action, movement, and joint layer, where the action layer plays a crucial role. An action is defined as a group of movements that take the robot from an initial positionorientation to another positionorientation. All actions form the action library, which can be combined to accomplish different tasks. Based on the hierarchical control framework, two tasks including path following and ditch crossing are achieved in this paper. The advantages of the proposed hierarchical control framework are its universality and extendibility since it can be easily applied to other tasks by enriching the action library. Simulation results in VREP are given to validate the effectiveness of the proposed method.