| Underwater target detection and perception technology is an important means of exploring ocean and military confrontation.The forward-looking sonar is small in size and light in weight,suitable for underwater exploration and perception of the water environment,which can make people "see" the situation in unknown waters,which occupies great significance in the goal of developing china’s marine strategy.Based on the forward-looking sonar and GPS system,this paper conducts research on the technology of object detection,positioning and target height recovery,designs relevant algorithms and performs system design,and presents a visual interface.Firstly,this paper designs the detection algorithm based on the characteristics of the forward-looking sonar.The sonar model used in this paper is Tritech Gemini 1200 ik,which filters the acoustic image detected by this sonar in practical applications,divides the seabed area and the water body area,and then performs edge detection for the water body area to select the seed point and formulates the target detection algorithm according to the selected seed point area growth algorithm,and detects the suspended target in the water body.At the same time,according to the supporting GPS device to obtain the sonar itself position information and steering angle,and the data obtained by this device and the target information detected by the forward-looking sonar for synchronous processing,the comprehensive acquisition of the target latitude and longitude location information.Secondly,perform a high degree recovery of the suspended target.For the sonar image of the detected target,determine whether it has a complete shadow,and determine the front edge of the target bright area on the basis of the previous target detection,and at the same time use the simplified radon transformation to determine the front edge of the shadow part of the sonar target to obtain the pitch angle information of the target,and restore the target height by determining the pitch angle information of the sonar.Finally,for practical applications,a forward-looking sonar target detection system was designed to carry sonar,GPS and other equipment on an unmanned boat and display it on the PC side.The system is suitable for Windows 10 platform,can achieve sonar image acquisition,target detection,detection target positioning,target height recovery function,in the PC side through Visual Studio 2017 and Qt Creator platform jointly built interface as a visual control interface,thus completing the design and implementation of the entire system.After experiments on the lake,it was proved that the system can detect targets in real time and complete the corresponding processing,and the whole system completed the expected functions. |
