Study On Attitude Algorithms Of Accelerometers/magnetometers Strap-down Inertial Navigation System

A system which only use accelerometers as the inertial measurement unit is called gyroscope free strap-down inertial navigation system(GFSINS).The research of GFSINS has the important significance owing to its outstanding virtues such as low cost ,low power, longevity ,high reliability and promote reaction. But it leads to the accelerated growth of navigation errors that the angular speed of carriers is got by accelerometers instead of gyroscopes. If the integrated navigation system of GFSINS and magnetometers is used, the navigation parameter errors are adjusted by the data obtained from magnetometers which meet the accuracy requirements for navigation systems during motion.This article key research content is: first, a new twelve-accelerometer model is set up based on analyzing typical six-accelerometer and nine-accelerometer model ,which adapt well to cases of projectile attitude measurement in the environment of high rate of revolution. not only the twelve-accelerometer model can be installed in limited space, but also of carriers can be expressed only by the output of accelerometers and the angular speed errors don't grow . second, after comparing and analyzing existing attitude algorithms, a conclusion is drawn that quaternion is more suited in application. the integrated navigation system of GFSINS and magnetometers is set up which adapt to cases of projectile attitude measurement in plane of trajectory, a new optimization algorithm of attitude is found based on the relation of the output of magnetometers and attitude angle and the theory of the optimization algorithm is introduced. Finally, the integrated navigation system is studied by simulation, which indicates the optimization algorithm controls the growth of errors effectually.The new way is found using integrated navigation systems integrated in the dissertation. it is possible that the integrated navigation system will be used in theory, and the study in the dissertation have the practical significance and the application prospect.