| 摘要 |
PURPOSE:To elevate the measuring accuracy of the vehicle speed, by setting two cameras at a specified distance and height from a reference measuring point o compute the vehicle speed from the height of the representative position of a vehicle and the apparent speed at specified time intervals. CONSTITUTION:Camera positions of first and second camera units 2 and 4 are set at respective specified distances and heights from a reference measuring point. Then, a speed measuring device is made up of vehicle positioning means 1 and 3 and a microcomputer 8 comprising a central arithmetic unit 9, a memory 10 and an input/output signal processing circuit 11. Video signals of a vehicle to be measured taken at a specified time and after a specified time interval with cameras of the first and second camera units 2 and 4 are inputted into vehicle positioning means 1 and 3 to detect the apparent position of the vehicle being measured. After the height of the representative position of a vehicle and the apparent speed are detected with the microcomputer 8 and the speed of the vehicle is computed. In this manner, the vehicle speed on a road surface in a wide range can be measured automatically at a high accuracy. |
