DCIST researchers pioneered strategies for teams of mobile robots to form intermittently connected communication networks by leveraging their mobility.  Robots assigned to monitor and patrol large urban environments can leverage their movements to carry information to other robots that are not within their communication ranges. Our work shows intermittent connectivity between pairs of robots can be achieved by synchronizing the robots’ motions and ensuring robots rendezvous or move into each other’s communication ranges periodically.  And while the network is not fully connected at any instance in time, it is guaranteed to be connected over a predetermined period of time ensuring the successful propagation of information across the entire network.  In addition, these strategies can be extended to guarantee resiliency of the mobile robot network in the presence of non-cooperative robots.  Resilience for a large intermittently connected mobile robot network is achieved by concatenating modular dynamic formations where each module is guaranteed to be resilient by design.

Left: The creation of a time-varying periodically connected in an urban environment by a team of mobile robots tasked to patrol different buildings.  Right: Two examples of time-varying networks formed using lattice modules.  Red nodes represent malicious agents.  Plots on the right show consensus formation in the network over time.

Capability: T3C2C Mobility to Extend Communication Networks 

Points of Contact: M. Ani Hsieh (PI), Xi Yu, Daigo Shishika, David Saldana

Paper: https://10.1109/LRA.2020.2967704, https://10.1109/TRO.2021.3088765 

Citation: X. Yu and M. A. Hsieh, “Synthesis of a time-varying communication network by robot teams with information propagation guarantees,” IEEE Robotics and Automation Letters, vol. 5, no. 2, pp. 1413–1420,2020.

Yu, D. Shishika, D. Saldana and M. A. Hsieh. “Modular Robot Formation and Routing for Resilient Consensus,” in the Proc. of the 2020 IEEE American Control Conference (ACC 2020), Jul 2020 (Virtual).

X. Yu, D. Saldana, D. Shishika, and M. A. Hsieh.“Resilient Consensus in Robot Swarms with Periodic Motion and Intermittent Communication,” in IEEE Transactions on Robotics and Automation (T-RO), 2021.