An Intelligent Identification and Acquisition System for UAVs Based on Edge Computing Using in the Transmission Line Inspection

Abstract

With the increase of the transmission line mileage, the transmission line inspection is facing severe challenges. As an efficient inspection way, the UAV (Unnamed Aerial Vechicle) is used for the transmission line inspection. However, at the present stage, to complete the observation and data collection of transmission line equipment, the PTZ (Pan Tilt Zoom) camera in the UAV is completely controlled dependent on the operator during the inspection. These needs higher requirements for the operator and lead to high labor intensity. And the image scale of the collection device is not uniform, which improves the difficulty of subsequent intelligent diagnosis of defects. In order to solve this problem, this paper designs an intelligent acquisition system for UAVs based on edge computing using in the transmission line inspection. The system includes the front-end edge computing detection module based on SSD (Single Shot Multibox Detector) algorithm and a PTZ camera control module. The system workflow is as follows: firstly, the UAV acquires the video stream data of the surrounding environment of the transmission line through the fixed-focus camera in the PTZ. The front-end edge computing detection module receives the video stream through the USB interface. And the front-end edge computing module uses the SSD algorithm to identify the video stream gotten from the PTZ camera to recognize and locate the transmission line equipment. Secondly, if the transmission line equipment is identified in the field of view, such as an insulator, the anti-vibration hammer, the equalizing ring, etc., the front-end edge computing module calculates the target image ratio of the device and from the center position based on the identified pixel position information of the transmission line equipment, and converts to the pan-tilt rotation amount and camera pulling factor. The pan-tilt rotation amount and camera pulling factor is transmitted to the PTZ camera control module through the serial port. The PTZ camera control module controls the camera's movement until the transmission line equipment is in the center of the field of view. Finally, the wide-angle camera in dual-view PTZ camera is controlled to zoom. And the image after the zoom is photographed and saved to finish a flow of the data of transmission line equipment collects. After testing, the SSD algorithm for transmission line equipment can achieve an overall recognition accuracy of 73%. The insulator identification accuracy is 75.7%.The anti-vibration hammer identification accuracy is 72.6%.And the equalization ring recognition accuracy is 70.3%.The acquisition video is 1080P, the edge computing module processing speed is 3fp/s, and the pan/tilt control module controls the pan/tilt camera to complete a shooting time of 3s. On the one hand, the system realizes the autonomy, process and standardized collection of the image information during the transmission line equipment while improving the validity of the image data information and reduces the complexity of the subsequent defect diagnosis. On the other hand, it also reduces the manual participation degree of the inspection operation so that the efficiency can be increased by 5~7 times compared with the manual control of the PTZ camera for equipment acquisition.