The Research Of SIN/EC Integrated Attitude And Heading Reference System For AUV

In the recent30years, the autonomous underwater vehicle (AUV) is playing a boomingdevelopment, it is necessary to acquire the effective information with the high-precision ofnavigation system and ensure its safety operation and return.It is difficult for the solo kind ofnavigation system to meet the requirement of the AUV because of the diversity andcomplexity of the task in the ocean. The inertial navigation takes as the main ways ofnavigator in underwater navigation and combines with Arry sonar, Doppler velocity log(DVL), Magnetic compass, and Depth meter together to become the integrated navigationsystem (INS) at present, which have a great effectiveness in AUV.The subjects constitute INS and geomagnetic sensor with DVL to integrated navigationsystem. Adopt the federal Kalman filter to realize the data fusion of geomagnetic sensor andDVL, and all of these achieved the basic function requirements of the integrated attitude andheading reference system (AHRS) preliminary.The thesis mainly includes the following four aspects of work:(1) First, make components selection about the Fiber optical gyroscope (FOG) andacceleration according to the purposes and the specific requirements of the subject.(2)Build an embedded system based on SOPC, which provide a hardware platform forthe follow-up navigation algorithm and error compensation. Get start from the principles andperformances of the FOG, Quartz accelerometer, GPS Receiver, DVL and geomagneticsensor. And also make the overall composition and design of the system which include circuitboard design, electrical connection, SOPC keneral build and underlying driver design.(3) Make a detailed analysis of the error model of the inertial sensors, and get theparameters of accelerometers and FOGs by calitration testing. Design a six-positioncalibration method to calibrate the environment impact on the scale factor and the bias of theaccelerometer, FOG, geomagnetic sensor.And also the method could recalibration the scalefactor and bias of all the sensors in the field environment.(4) Reserch the two structures of strapdown inertial navigation system (SINS), that is,quaternion method and rotation vector algorithm, analysis the three sub-sample rotaion vectoralgorithms. And also study the optimal rotation vector algorithm under the cone movementconditions and made a rough estimation of the algorithm drift combine. The simulation testsdemonstrate the high-precision of the algorithms, and also the simulation analysis showed thatthe filter algorithm can improve the attitude accuracy of the intergrated AHRS effectively. (5) Adopt the satellite navigation and positioning method by using the output singal ofGPS positioning system as the standard singal to calibrate the inatallation derivation of SINSand DVL and scale factor of DVL. After that the ocean experiment has been done to verifythe simplification and effectiveness of the calibration method and have proved that thepositioning precision have improved to a large extent after calibration by analysising theexperimental data.