  Control and communication are often tightly coupled in motion planning of
networked mobile robots, due to the fact that robotic motions will affect the
overall communication quality, and the quality of service (QoS) of the
communication among the robots will in turn affect their coordination
performance. In this paper, we propose a control theoretical motion planning
framework for a team of networked mobile robots in order to accomplish
high-level spatial and temporal motion objectives while optimizing
communication QoS. Desired motion specifications are formulated as Signal
Temporal Logic (STL), whereas the communication performances to be optimized
are captured by recently proposed Spatial Temporal Reach and Escape Logic
(STREL) formulas. Both the STL and STREL specifications are encoded as mixed
integer linear constraints posed on the system and/or environment state
variables of the mobile robot network, where satisfactory control strategies
can be computed by exploiting a distributed model predictive control (MPC)
approach. To the best of the authors' knowledge, we are the first to study
controller synthesis for STREL specifications. A two-layer hierarchical MPC
procedure is proposed to efficiently solve the problem, whose soundness and
completeness are formally ensured. The effectiveness of the proposed framework
is validated by simulation examples.
