Scheduling for offloading safety-critical applications within networked groups of vehicles

This paper presents a combined scheduling and path planning scheme for offloading of safety-critical applications in a group of networked vehicles. Due to the dynamic nature of such systems, a scheduler for applications to be offloaded needs to account for the changes of the network parameters. Such a scheduling scheme based on a mixed-integer program (MIP) is detailed with attention to the time-varying duration of message passing operations. Given knowledge of the scheduling requirements of applications to be offloaded, a path planner for a group of networked vehicles can ensure the resulting path will yield a feasible schedule for offloading. An method for generating such a path is described, utilizing the scheduling scheme and a mixed-integer program for path planning with integral communication capacity constraints. The combined scheme is demonstrated in a case study consisting of a pair of UAS equipped with a line-of-sight inter-vehicle a communication link and onboard processors. We show how the scheme can be used to make individual vehicles of the group fault-tolerant to processor failures.