Abstract:The extraction of spatio-temporal information of bridge traffic vehicles and the tracking of vehicle trajectories are realized by the secondary development of YOLOv5 machine vision framework, while incorporating DeepSORT tracking algorithm. Then the traditional virtual coil method is improved to achieve the measurement of vehicle speed, which avoids the setting of threshold value due to the pixel change of detection coil in the traditional method and improves the universality of the algorithm. Finally, the algorithm is applied to the actual scene to compare with the tachymeter results, in which the average error is within 1% and the maximum error is controlled within 15%.