Reaction Latency Analysis of Message Synchronization in Edge-assisted Autonomous Driving

Abstract

In the realm of connected autonomous vehicles, the integration of data from both onboard and edge sensors is vital for environmental perception and navigation. However, the fusion of this sensor data faces challenges due to timestamp disparities, particularly when edge devices are involved. The Robotic Operating System (ROS) addresses this with synchronization policies like Approximate and Exact Time, along with the newer Synchronizing the Earliest Arrival Messages (SEAM). Understanding SEAM’s performance in edge-assisted environments is crucial yet under-explored. This paper presents a comprehensive analysis of SEAM synchronization within ROS. Our study focuses on critical latency metrics for ROS message synchronization in edge-assisted autonomous driving. Specifically, we analyze two key latency metrics, the passing latency and reaction latency, which are needed to analyze the end-to-end delay and reaction time on the system level. We conduct experiments under different settings to evaluate the precision of our proposed latency upper bounds against the maximum experimental latency in simulation.