Design And Implementation Of Real-time Underwater Target Location And Attitude Measurement System

With the deepening of human exploration in the ocean and the growing development of underwater technology,the enhancement of comprehensive marine strength has become a concentrated reflection of the military forces of various countries.At present,underwater real-time positioning system has been widely used in military field.Through underwater positioning technology,real-time positioning data of underwater targets can be obtained and the azimuth and attitude of the target are obtained by the position information obtained by multiple beacons mounted on the vertex of the target,and then the trajectory state of the target is analyzed.Starting from the overall structure of the system,this paper designs and implements a real-time positioning and attitude measurement system for underwater targets.The system can make a real-time positioning of underwater moving targets every half second through time delay estimation and synchronized positioning method.The position information of beacons installed in different positions of the target acquired in the previous step is used to calculate the position and attitude of the target.Finally,the position and attitude information of the target is transmitted to the host computer in real time and displayed.This paper mainly includes the structure of positioning and attitude measurement system,the design and implementation of software and algorithm,system simulation and pool experiment,as follows.1)Framework design and implementation of the system: Firstly,the overall design scheme of positioning and attitude measurement system is put forward,including system scheme,model and framework design.Then the hardware modules of the system are introduced,such as signal transmitting,receiving and processing units,underwater acoustic transducer array and hydrophone array.In addition,the PCB baseboard with integrated signal transmitting,receiving and processing functions developed independently is also included,and its parameters,design ideas and design schemes are introduced in detail.2)Software design and implementation of the system: Design and develop a suitable embedded C driver for the signal transmitting,receiving and processing module designed and developed independently.Considering the real-time and positioning accuracy requirements of positioning and attitude measurement system,this paper optimizes and improves the embedded C driver with assembly language.3)Algorithm design and implementation of the system: Five algorithms are studied in this paper,including filtering,location,time delay estimation,solution of non-linear equation and azimuth attitude measurement.The differences of real-time performance and positioning accuracy of different algorithms in these five aspects are compared and analyzed.A set of algorithms suitable for real-time positioning and attitude measurement system is selected.Finally,the development of the system in terms of algorithm is completed.4)System simulation and pool experiment: Through the simulation experiment of MATLAB,the error of the positioning and attitude measurement algorithm is analyzed.And then the real-time positioning and attitude measurement system designed independently is used in the anechoic pool.Experiments show that the accuracy of the system in positioning and attitude measurement is basically consistent with the simulation results,and the system has achieved ideal results in real-time performance.