In recent years, mobile robots are expected to function properly even in harsh environments such as disaster sites and space environments that humans cannot reach.However, in many robots, when an unexpected failure occurs, it takes tens of seconds to several minutes to adapt to the failure.

　On the other hand, many animals can adapt immediately even if a part of their body is injured.Therefore, this research group decided to be inspired by the movement of animals, and especially focused on the animal called brittle star.Brittle stars have a five-radiation symmetry body structure consisting of a board and five arms, and even if they lose their arms due to being attacked by a foreign enemy, they can be immediately coordinated regardless of how many arms remain. You can move around.Even more surprising, brittle stars do not have the central nervous system responsible for advanced information processing like the "brain."

　The research group speculated that the brittle star's extraordinary fault tolerance is realized by autonomous decentralized control that determines movements in various parts of the body based on local sensory information. Based on the behavior observation results, we designed an autonomous decentralized control rule described by an extremely simple mathematical formula that "kick the ground only when each arm receives a reaction force from the environment in the direction of travel."Then, by implementing this control rule, we succeeded in developing a brittle star type robot that adapts and continues to move within a few seconds no matter how the arm is destroyed.

　This result leads to the realization of a robot with high adaptability that can cope with unexpected events, and also provides important knowledge for elucidating the principle of real-time adaptive ability of animals.

Paper information:[ROYAL SOCIETY OPEN SCIENCE] A Brittle Star-like Robot Capable of Immediately Adapting to Unexpected Physical Damage