| 摘要 |
<p>The traffic light coordination control system is of the type which uses vehicle detectors. It also uses elements which switch the traffic lights at crossroads according to a periodic cycle corresponding to an determined plan. A logic element processes the plan as a function of the data collected by the detectors. At least some of the detectors, alone or in association furnish magnitudes representing vehicle flow as well as occupation rate to the right of the detector. The system only detects the number of vehicles passing in unit time. Some of the detectors are of a type sensitive to the presence of a vehicle, whether immobile or moving very slowly. A simple buried magnetic loop is used for counting. The flow and occupation rates are measured in various places by separate detectors or by a single element capable of supplying itself both types of information. The logic element calculates at regular intervals the average values of each secondary magnitude. These values each define a coordinate of a point in a space having as many dimensions as there are detection points. The distance of the point from fixed reference points is calculated to determine plane to be used.</p> |
