This letter focuses on a scenario in which a team of sensing robots survey an area with predefined routes, and transmit the monitored information to a remote base station through a mobile relay. In this scenario, automatically adjusting the position of the mobile relay for maintaining wireless link quality while the sensing robots are moving is a challenging problem. In this letter, we consider the problem of minimizing the total energy consumption. We propose using dynamic programming (DP) and single-step optimization. By comparing the pros and cons of both methods, we propose a novel approximate optimal communication-motion planning (AOCMP) method based on approximate dynamic programming (ADP). Simulation results demonstrate that AOCMP may sharply decrease the computation time compared with DP, while performs better than single-step optimization which proves that AOCMP achieves a beneficial energy-complexity tradeoff for solving high-dimension problems.

Wireless communications and networking are playing an important role in coordination and cooperation of multi-robot systems (MRS). However, it is challenging to keep a reliable and stable wireless connection in practical applications. Especially, robots acting in electromagnetic adversarial (EA) environments may encounter more serious situations including scarce spectrum, active interference, adversarial competition, etc. In this survey, we firstly analyze the challenges faced by MRS in EA environments, and provide a categorization according to the “sense-decide-act” robot control procedure. Secondly, enabling techniques for each challenge are introduced. Finally, typical robotics software architectures are introduced, as frameworks for efficient arrangement of the above mentioned enabling techniques.

In this paper, we propose micROS.BT, an event-driven behavior tree (BT) framework aiming at supporting swarm-robot coordination. Compared with other BT frame-works, micROS.BT implements the event-driven way under the multi-thread mode, which can effectively save computing resources. Moreover, in order to ensure swarm-robot coordination, we optimize the implementation of the traditional blackboard and propose the multi-mode blackboard, which supports inner-tree, inter-tree, and inter-robot data sharing. Furthermore, considering the limited modularity of a single tree, micROS.BT realizes a mechanism called hierarchical tree management which involves inter-tree notifying and waiting functionalities, while ensuring that each tree is independent and self-scheduled. The effectiveness of micROS.BT is verified by simulation and real-robot experiments for different system settings, showing that a substantial improvement is achieved in comparison with the traditional BT implementations.