Presently in Japan, signal control parameters (cycle length, splits, and offset) are determined based on traffic volume data collected from vehicle detectors in order to effect proper signal control according to traffic demands. However, a time lag takes place in signal control that much by the time interval required for data collection. As a signal control technique that can meet traffic demands in real time, the conventional control technique still has room for further improvements or more sophistication. So, to solve this time lag problem, researchers at the Hokkaido Prefectural Police HQ developed on an experimental basis a new prediction-based signal control technique which determines control parameters by predicting the arriving states of vehicles at individual signalized intersections based on traffic volume data collected from each vehicle detector at intervals of several seconds. To verify the effectiveness of this new control technique, the researchers introduced a signal control system employing the new control technique on a trial basis into an about 2-km long roadway section within Sapporo City, Hokkaido Prefecture and evaluated the results of the field testing, which were found to be favorable.
Abstract