Avoidance Sonar Data Acquisition And Processing System

It is premise and foundation for the obstacle avoidance technology of unmanned underwater vehicle to achieve safe navigation and the completion of all scheduled tasks underwater. so unmanned underwater vehicle avoidance of obstacles gains more and more attention in today's various countries. This research is focus on avoidance sonar data acquisition and processing system for the obstacle avoidance technology of unmanned underwater vehicle to provide adequate and accurate information on the external obstacles. It directly affects the unmanned underwater vehicle safety. This thesis is mainly including system design and construction, sonar data acquisition, sonar data processing of three parts.System design and construction component designs a collision avoidance sonar data acquisition and processing system. This system conforms to the current obstacle collision avoidance technology of unmanned underwater vehicle of the latest developments, it also meets the requirements of unmanned underwater vehicle features in the subject.Avoidance sonar data acquisition part mainly introduces SeaKing mechanical scanning sonar RS232 communication protocol and the sonar image data acquisition. The sonar image data will be collected out of coordinate transformation and interpolation beam to form a convenient machine processing and recognition of bitmap data.Avoidance sonar data processing is a core part of this thesis. the collected sonar data needs the sonar image denoising smoothing, image enhancement, image segmentation, image processing, and other methods for different types of sonar image noise. Then it contour area threshold set to retain the outline of a large area, removing a small area of the noise by the contour extraction algorithm sonar image of the enclosed space of contour extraction. At last the information based on morphological characteristics extracted sonar image of the obstacle information (obstacle size, distance), is conveyed to the central control unit of unmanned underwater vehicle.Through the underwater laboratory,and field experiments at sea, the sonar data acquisition and processing part of the performance perform a series of tests. Experimental data show that the detected obstacle information has good stability and reliability, it basically achieves the purpose of this research issue.