This study proposes a bi-connectivity control algorithm for a multi-robot system consisting of a robot that communicates through line-of-sight communication. Optical observation and communication require a line of sight to a subject, and a robot in a multi-robot system sometimes impedes the line of sight between other robots. The motion of individual robots may violate the connectivity of the communication network. A distributed control strategy for bi-connectivity was constructed by modifying a previous method that does not consider line-of-sight restrictions. The results of the numerical simulation and experiments with actual robots are reported to emphasize the validity of the proposed control method.

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