In intersection signal timing, pedestrian is quite often treated as a "slave phase" (while vehicle is master phase) that results in unnecessary pedestrian delays, and evoke high pedestrian signal violation rates. Some existing pedestrian control strategies at midblocks such as HAWK and PUFFIN have been applied and proved to be able to improve pedestrian safety and avoid unnecessary delays, however, they will have difficulties to operate smoothly at intersections with high vehicle flow from multi-directions and very frequent pedestrian crossing requests. Therefore, a new rule-based dynamic pedestrian control (DPC) strategy accommodating pedestrian in intersection signal system has been proposed in the study. Phase structure including 8 vehicle phases and 4 pedestrian phases for a four-leg intersection has been introduced, and a set of rules regulating phase combination, phase sequence, and phase transition (internal and external) has been established. Different from previous control strategies, pedestrian is not a "slave phase" in DPC, but a decisive factor equal with vehicles for signal timing optimization with consideration of pedestrian safety and comfort. According to simulation results, DPC is beneficial to reduce traffic delay at intersections crossed by a major street and a minor street, and it makes a good trade-off between pedestrians and vehicles. DPC is suitable for both peak hours and non peak hours, and it is compatible with National Electrical Manufacturers Association (NEMA) controllers. However, the results concluded were based on the assumption that the detection accuracy is 100%, while it is impossible in reality, therefore, different accuracy of detection will be tested in the next step and the control strategy will be updated further.
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