CoCoSim: A Tool for Co-simulation of Mobile Cooperative Robots.

High-quality and efficient simulation is a critical component of robotics development and research. Currently, simulations for multi-robot systems are split across several independent tools, such as Gazebo for physics and mobility, ROS2 for software development, and ns-3 for communications and networking infrastructure. Those are mature, well-tested tools worth reusing that implement different modeling techniques, interfaces, and, more importantly, time-passing representation strategies; Gazebo uses fixed time steps and ns-3 discrete events. This article presents CoCoSim, a framework that integrates both simulators to allow multi-robot co-simulation, capable of running experiments that combine all the involved robotic systems. We show how the time synchronization and data exchange between the simulators that keeps a consistent state across them is achieved with minimal modifications to their original code.