  The challenges in implementing SAE Level 4/5 autonomous vehicles are
manifold, with intersection navigation being a pervasive one. We analyze a
novel road topology invented by a co-author of this paper, Xiayong Hu. The
topology eliminates the need for traditional traffic control and cross-traffic
at intersections, potentially improving the safety of autonomous driving
systems. The topology, herein called the Zonal Road Topology, consists of
unidirectional loops of road with traffic flowing either clockwise or
counter-clockwise. Adjacent loops are directionally aligned with one another,
allowing vehicles to transfer from one loop to another through a simple lane
change. To evaluate the Zonal Road Topology, a one km2 pilot-track near
Changshu, China is currently being set aside for testing. In parallel, traffic
simulations are being performed. To this end, we conduct a simulation-based
comparison between the Zonal Road Topology and a traditional road topology for
a generic Electric Vehicle (EV) using the Simulation for Urban MObility (SUMO)
platform and MATLAB/Simulink. We analyze the topologies in terms of their
travel efficiency, safety, energy usage, and capacity. Drive time, number of
halts, progress rate, and other metrics are analyzed across varied traffic
levels to investigate the advantages and disadvantages of the Zonal Road
Topology. Our results indicate that vehicles on the Zonal Road Topology have a
lower, more consistent drive time with greater traffic throughput, while using
less energy on average. These results become more prominent at higher traffic
densities.
