Arterial signal coordination optimisation model: variable bandwidth and balanced path coordination

Arterial traffic signal coordination makes traffic flow more efficient and safer. However, most existing models focus solely on through traffic or critical path-flows, resulting in local traffic issues, such as left-turn queue spillback. Thus, this paper presents an enhanced multi-path signal coordination model. The proposed model treats a road link as a coordination unit, which allows the model to better utilize the available green time and provide additional opportunities for vehicular progression. The proposed model coordinates both critical and ordinary paths. The global progression bands are employed to coordinate critical paths, ensuring continuous travel along these paths. The local progression bands are used to manage ordinary paths, enhancing the throughput efficiency of high-volume local traffic flows. Numerical results demonstrate that the proposed model significantly improves bandwidth on critical paths and provides local bands for high-volume segments of ordinary paths. It also outperforms four benchmark models across multiple performance metrics.