As the lead inventor, granted the U.S. patent for the smart and scalable urban traffic control system.
- X.-F. Xie, et al. Smart and Scalable Urban Signal Networks: Methods and Systems for Adaptive Traffic Signal Control. U.S. Patent, No. 9,159,229, 2015.
Scalable urban traffic control (surtrac) system has been developed to address current challenges and offers a new approach to real-time, adaptive control of traffic signal networks. The methods and system described herein exploit a novel conceptualization of the signal network control problem as a decentralized process, where each intersection in the network independently and asynchronously solves a single-machine scheduling problem in a rolling horizon fashion to allocate green time to its local traffic, and intersections communicate planned outflows to their downstream neighbors to increase visibility of future incoming traffic and achieve coordinated behavior. The novel formulation of the intersection control problem as a single-machine scheduling problem abstracts flows of vehicles into clusters, which enables orders-of-magnitude speedup over previous time-based formulations and is what allows truly real-time (second-by-second) response to changing conditions.