Construction Of Unmanned Surface Vehicle With Polarized Light Sensor

About two thirds of the earth is covered by oceans,but only a few are fully explored.Issues such as climate change,environmental anomalies,resource exploration,and national security are all lead to strong demand for unmanned surface vessels(USVs).The accuracy of individual navigation information is the cornerstone of unmanned ship navigation and formation.However,the traditional inertial and geomagnetic navigation is difficult to obtain accurate and stable course and position information in complex aquatic environment due to the shortcomings of error accumulation and susceptibility to interference.Therefore,the integration of other sensor information to assist in improving navigation performance has attracted the attention of scholars.Polarized light sensor is a new directional navigation sensor,which has been used in unmanned ground vehicles and unmanned aerial vehicles,but its application in the field of unmanned surface vehicles is still a blank.This paper aims to realize the application of polarized light sensor in USV navigation.Firstly,an information fusion algorithm based on polarized light sensor,micro-inertial unit(MIMU)and global positioning system(GPS)is designed by using the extended Kalman filter technology,and the software simulation is completed.The formation strategy of USV is studied and simulated.Then,the horizontal three-degree-of-freedom dynamics model of the USV is derived and simplified,and the transfer function of the system is obtained.Based on this,the cascade PID controller of speed and position is designed.The optimal parameters at all levels are obtained by MATLAB simulation,which verifies the effectiveness of the algorithm and provides a reference for hardware selection.Then,the USV experiment platform of polarized light sensor is built.The overall design scheme is given,and the microprocessor module,sensor module,communication module and power system are selected according to the requirements.At the same time,in order to deal with the loss of alignment of polarized light sensor to sky vertex caused by the fluctuation of water surface and ship tilt,the base of the cradle and its software control system are designed.Increase the ability of the ground station to display and record polarized light angles.Finally,the experiment of USV navigation and formation based on polarized light integrated navigation system is carried out.The static and tracking experiments of the polarized light sensor /MIMU/GPS combined navigation system and the magnetic compass/MIMU/GPS combined navigation system are carried out in the environment with magnetic interference.The results show that the trajectory deviation of the polarized light integrated navigation system is 0.209 m and the course Angle deviation is 6.055°,which is 23.3% and15.7% higher than that of the magnetic compass integrated navigation system,respectively,under the condition of electromagnetic interference in some trajectories.Based on the sensor output consistency experiment,the formation experiment based on the polarized light integrated navigation system is carried out,and the results show that the trajectory errors of the leader and the follower are 0.425 m and 0.707 m,respectively.