Search

Pedestrian signal timings are one of the major issues to be addressed when developing signal timing plans. So far, two different treatments of pedestrian timings for coordinated systems exist. The first treatment accommodates pedestrian timing within the cycle. Therefore, it requires longer cycle lengths that usually increase the total delay on the network. In contrast, the second treatment uses shorter cycle lengths sufficient to serve vehicular demand only. The problem with the latter is that the concurrent phase is usually not long enough to serve pedestrians. Thus, with every pedestrian call, a follow-up transition process occurs, affecting cycle lengths and coordination quality. This study develops two novel pedestrian timing treatments to overcome the problems of the traditional ones. Novel pedestrian treatments utilize a cycle length optimized to cover necessary times for vehicular phases, although pedestrian timings may require longer time intervals. However, when pedestrian calls occur, their minimum safety timings are accommodated within such a shorter cycle, and thus the transition process is not required. Our study evaluates the proposed and traditional pedestrian timing treatments using a corridor of five signalized intersections in West Valley City, Utah. Various experiments were conducted in a microsimulation environment VISSIM and collected results were statistically compared. Results show the promising property of the proposed treatments, as they outperformed the traditional pedestrian timing treatments. Therefore, further investigation of these pedestrian timing treatments is warranted. Future research should investigate possibilities of implementing similar treatments to fully actuated control systems on various networks and traffic conditions.

Numerous studies have assessed video detection systems, but automated pedestrian video detection systems (APVDS) have not received as much attention. Although some researchers have evaluated the accuracy of APVDS, none quantified the consequential effects that false or missed pedestrian calls have on critical vehicular and pedestrian performance metrics. To address this gap, this study introduces a microsimulation-based approach to analyze the impact of missed and false pedestrian calls on signalized intersection operation. This method employs simulation inputs that mimic various detection scenarios from the field, allowing for greater flexibility in analysis. Additionally, the study compares the impacts of incorrect calls under different operational strategies, including APVDS with and without the pedestrian recycle feature of the controller, pedestrian recall operations, and common push-button operations with or without pedestrian recycle. Results show that the proposed microsimulation approach is a valuable tool for future studies, especially considering the idiosyncratic nature of specific sites where the percentage of false and missed calls depends on local conditions. The study reveals that neither of the two analyzed APVDS systems is mature enough to work as a standalone option. Microsimulation results show that even though the single-camera video detection system (VDS) appears to be a safer option than the double-camera VDS, it fails to provide any benefits in pedestrian and vehicular delay over the pedestrian recall operations. This research may be of practical significance as transportation agencies could utilize the proposed microsimulation approach to evaluate APVDSs effectively. Knowing the strengths and limits of APVDS can help agencies make informed implementations.