UPPAAL-Based Modeling and Verification of ROS 2 Multi-threaded Execution and Operating System Reservations

In this paper, we propose a formal modeling approach in Uppaal to simulate and verify multi-threaded robotics middleware execution based on ROS 2. In the modeling process, we consider middleware-specific scheduling by creating formal models that simulate the execution behavior of a ROS 2-based system. Furthermore, we show how to model potential underlying operating system’s influences on execution, by modeling reservation servers. We propose timed automata templates to model the multi-threaded execution of ROS 2 systems and the reservations of the underlying operating system in Uppaal. We show how to use the created templates to simulate a ROS 2 application. We demonstrate the application of the formal models and model checking in various ROS 2 experiments. Furthermore, we validate the created models by comparing the observed execution traces in experiments on ROS 2 systems and the simulated traces of our models. Overall, this paper showcases the application and usefulness of model-based verification of distributed middleware applications, including internal scheduling and influences of underlying operating system actions.