Spatio-Temporal Coordination of Mobile Robot Swarms

Context-aware applications that require access to physical space and time are a necessity in cyber-physical systems. We focus on the design of a cyber-physical operating system in which a space-time scheduler is the core-component responsible for resource management. Given a set of space-time tasks and a set of mobile robots that move through physical space, a main objective remains in finding a mapping of tasks to robots. In this paper, we address the problem of scheduling a set of tasks with spatio-temporal constraints in space and time. We present an online-scheduler that computes collision-free spatio-temporal trajectories for the robots in order to execute the space-time tasks. As side condition, collisions with static as well as dynamic obstacles must be avoided at all times. The scheduler consists of two components: a job scheduler that uses a heuristic and performs a coarse-grained scheduling and a trajectory planner that takes the output of the job scheduler and computes spatio-temporal trajectories.