Abstract:In order to detect the state of the pandrol fast projectile fastener,A method of synchronous control of linear camera based on external trigger mode,is used to ensure that the fastener’s images be collecting undistorted when the train’s speed changes.Preprocessing the collected images,and using cross crossing method to locate and extract fastener area.A template matching method based on fast normalized cross correlation algorithm is used to locate the fastener insulation cap and fixed bolt position in fastener area and obtain its central coordinate parameters,then,a recognition method of fastener status based on feature distance is proposed.The experiment of image acquisition railroad car proves that the synchronization control method can ensure that the images collected by linear array camera do not produce longitudinal distortion when the train is running at variable speed;Further experiment shows that the matching speed of the fast normalized cross correlation algorithm is improved by nearly 60% compared with the normalized cross correlation algorithm;At the same time,the experiment proves that the method based on feature distance can recognize the state of the pandrol fast projectile fastener.