Autonomous vehicles need to run robust autopilot software in resource-constrained environments. Such vehicles are increasingly built on ARM platforms with resources to spare. We have begun investigating the feasibility of using this spare capacity to implement other interesting services on these vehicles by using Xen to separate the real-time autopilot software from a richer, non-real-time Linux system. In order to make this work, we have ported FreeRTOS, a popular minimal operating system for microcontrollers, to run as a Xen guest on the ARM Cortex A15.