Research And Implementation Of The Integrated INS/Gravity Matching Navigation Algorithm

Inertial navigation system(INS)has the feature of passivity,stealth and all-weather which are required by modern navigation system.INS is the basic navigation method of underwater vehicles.To overcome the intrinsic defect of INS,which is that the error of INS is accumulated over time,the integrated navigation system which includes the dominated INS and another auxiliary navigation method is the development trend of modern navigation system.The integrated INS/gravity matching navigation system can obtain the position of underwater vehicle by using the gravity field data which is provided by high-resolution gravity field database to correct the error of INS.In this paper,aiming at the positioning accuracy requirement of the integrated INS/gravity matching navigation system,the integrated matching navigation system is designed based on embedded real-time operation system.On the basis of analyzing the component and the function of integrated matching navigation system,the programming design of the the integrated matching navigation system is realized.The matching algorithm is the key component of the integrated INS/gravity matching navigation system.Focusing on the sample degeneration and impoverished problem of conventional particle filter in the non-Gaussian and nonlinear system,differential evolution algorithm is incorporated into the resampling process of the particle filter.The distribution of particles is optimized by differential evolution algorithm which realizes the global search by the differences among the population.And then the matching positioning accuracy is improved by improving the filtering accuracy.Simultaneously,on the basis of the sea experiment data of a certain INS,the navigation error of kinds of algorithms are compared and analyzed under the same condition.And then the impacts of the performance of gravimeter and the resolution of gravity map on the navigation error are also analyzed.The navigation system is developed by QNX operation system,which is the embedded real-time operation system.The navigation system can realize that the processing of the sensor data which is collected by data recording and processing circuit.And it can also implement the matching position computation by using the particle filter based on differential evolution algorithm.The UI is designed by PhAB,and the function of updating real-time navigation information,displaying real-time track of underwater vehicle and setting the navigation parameters.The device driving of PCI is designed and implemented.The navigation system is implemented based on the gravity field data,the functions of the navigation system are validated by the sea experiment data of a certain INS and gravimeter simulator.