Realization Research Of Gyroscope Free Strapdown Inertial Navigation System Based On DSP

So-called GFSINS (gyroscope free strapdown inertial navigation system) is a kind of strapdown inertial navigation system with only accelerometers but no gyroscope. Because of no gyroscope, a series of difficulties caused by the narrow dynamic operating range of gyroscopes can be avoided. Compared with SINS, GFSINS has the characteristics of low cost, low power consumption, fast response, high reliability, long lifecycle, and so on. Because of the above advantages of GFSINS, it may become the important development direction of SINS in the future.In GFSINS, it is needed to calculate the specific force at the carrier's centroid and the angular acceleration round the carrier's centroid according to the specific force signals of the accelerometers installed at the carrier's non-centroid, then the carrier's ground velocity at centroid and the angular velocity round the carrier's centroid can be calculated. In view of the calculation amount, GFSINS' calculation is much larger than the SINS' So the high speed navigation computer is required to meet the need of real time navigation calculation. Usually, classical GFSINS used current CPU as its central processor. Thus system needs many circuit boards, which may cause big volume and weight. And the cost is very high. In this paper, DSP (TMS320C6711) is used as the central processor of the GFSINS. The integrated level, volume and weight of this system will be reduced. At the same time the calculation speed and precision will be improved.The research work carried out in this paper is as follows:1. The specific force equation at the noncentraled of the body is deduced. The calculation precession of GFSINS is given, which is the base of the DSP program.2. The structure of DSP is studied, and then the DSP chip is chosen. According to the requirements of the GFSINS, collectivity plan and the hardware circuit are designed.