| 摘要 |
An automatic vehicle detection system within a toll collecting system has a scanning laser unit positioned on one side of a roadway, a vertical photoelectric detector on the opposite side of the roadway and a treadle extending across the roadway. The laser beam scans the height of the detector at regular intervals, and the detector produces a first signal indicative of a vertical dimension of an object (car or truck) intercepting the laser beam. The treadle detects each set of wheels and produces a second signal indicative of a horizontal length of the object. A control circuit uses the first and second signals to generate a count of the number of objects and to categorize each object as one of a plurality of known vehicles.
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