Error Analysis And Simulation Of Strapdown Inertial Navigation And Positioning Algorithm For Astronomical For Ship

The flaw of accurate guidance weapon is exposed step by step in the information's war. When the weapon of height is near outer space, the atmosphere is rarefaction and low refraction in which is fit for the star tracker working. It is possibility that the Global Positioning System(GPS) will be replaced by the Celestial Navigation System(CNS). Most of developed nation plough a large sum into the technique researching. so the CNS appear in the weapons, battleplans and satellites. The CNS is traceable the voyage, but it is lentitude that the subaerial methods of CNS. In view of this problem, the subaerial methods of CNS will be lucubrated in dissertation.At the beginning of dissertation, the method of CNS based on the platform navigation system is put forward, it will get the position information of navigation using the CCD star tracker that observes the position of stars in the sky at any time fixed on the platform. Because the errors are in the platform navigation system, it has a direct impact on the navigation precision. At the same time, the way of alignment on the sea without any information of position is bringed forward to instead of the GPS that have an influence on the alignment precision of subaerial weapon systems. In the scheme of alignment, the calculating process of rude alignment and information of position will be describe carefully.In the second part, a integrated navigation method using CCD star tracker and strapdown inertial navigation system will be studied to make the vessels be safe in any complexions. The integrated navigation method is on standby, because the output data of CCD star tracker and Strapdown Inertial Navigation System(SINS) will be calculated, the CNS and SINS will be complete independence. The output data of the integrated navigation method may improve the navigation precision of SINS.The errors of CCD star tracker and strapdown inertial navigation system will be analysed to get the result that the level error angles provided by the strapdown inertial navigation system and CCD star tracker have a direct impact on the navigation precision while the heading error angle has nothing to do with it.In the third part, The parameter of gyro is important for the navigation precision of SINS. transfer alignment measure based CCD star tracker could estimate the gyro drift and accelerometer bias to make the position information of navigation be perfect after the more hours. In the blue print of "velocity+attitude", the data of attitude will be got by CCD star tracker and SINS, and the data of velocity will be got by SINS. Transfer alignment measure based CCD star tracker could estimate the gyro drift and accelerometer bias. The estimation accuracy is influenced by time.SINS is in communication with more fields.The error of velocity, latitude information and attitude are feedback, so the navigation precision of SINS will be influenced by time and the error of longitude that doesn't produce feedback. Inertial navigation system without gyro will be found in the dissertation to resolve the circumstantiality that the gyro drift and the information of position diverge. The error of velocity, latitude information, attitude and longitude information are feedback in the inertial navigation system without gyro that include CCD star tracker and accelerometers. The inertial navigation system without gyro will be analysed to get the result that error of CCD star tracker and initial position information, and accelerometer bias have a direct impact on the navigation precision, the position information will be not diverge as time goes by and Schuler period will be in it. The inertial navigation system without gyro could make weapon systems work perfectly in any time.