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Max-pressure (MP) signal timing is an actuated decentralized signal control policy. Rigorous mathematical studies have proven the stability properties and established the benefits of different MP policies. However, theoretical studies make assumptions about traffic properties that may not represent reality and whose effects are not explored much in the literature under realistic traffic conditions. This study focuses on examining how different variations of MP perform in realistic scenarios and on finding the most practical policy among those for implementation in real roads. Microsimulation models of seven intersections from two corridors, County Road (CR) 30 and CR 109 from Hennepin County, Minnesota were created. Real-life demand and current signal timing data provided by Hennepin County were used to make the simulations as close to reality as possible. In this paper, we compare the performance of current actuated-coordinated signal control with an acyclic MP and two variations of cyclic MP policies. We present the performance of different control policies as delay, throughput, worst lane delay, and number of phase changes. We also present how different parameters affect the performance of the MP policies. We found that better performance can be achieved with a cyclic MP policy by allowing phase skipping when no vehicles are waiting. Our findings also suggest that most of the claimed performance benefits can still be achieved in real-life traffic conditions even with the simplified assumptions made in the theoretical models. In most cases, MP control policies outperformed current signal control.
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Total-delay-based Max Pressure: A Max Pressure Algorithm Considering Delay Equity
This paper proposes a novel decentralized signal control algorithm that seeks to improve traffic delay equity, measured as the variation of delay experienced by individual vehicles. The proposed method extends the recently developed delay-based max pressure (MP) algorithm by using the sum of cumulative delay experienced by all vehicles that joined a given link as the metric for weight calculation. Doing so ensures the movements with lower traffic loads have a higher chance of being served as their delay increases. Three existing MP models are used as baseline models with which to compare the proposed algorithm in microscopic simulations of both a single intersection and a grid network. The results indicate that the proposed algorithm can improve the delay equity for various traffic conditions, especially for highly unbalanced traffic flows. Moreover, this improvement in delay equity does not come with a significant increase to average delay experienced by all vehicles. In fact, the average delay from the proposed algorithm is close to—and sometimes even lower than—the baseline models. Therefore, the proposed algorithm can maintain both objectives at the same time. In addition, the performance of the proposed control strategy was tested in a connected vehicle environment. The results show that the proposed algorithm outperforms the other baseline models in both reducing traffic delay and increasing delay equity when the penetration rate is less or equal to 60%, which would not be exceeded in reality in the near future.
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- Award ID(s):
- 1749200
- PAR ID:
- 10403492
- Date Published:
- Journal Name:
- Transportation Research Record: Journal of the Transportation Research Board
- ISSN:
- 0361-1981
- Page Range / eLocation ID:
- 036119812211470
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1177/03611981221147051
