18-Position calibration algorithm for SINS

Aiming at getting rid of the dependence of high precision external attitude reference, this paper presents a 18-position calibration algorithm. This method takes the accelerometer output as observation, adopting reasonable transposition arrangement to fully motivate the relation between the observation quantity and the inertial instrument error, using the least squares method complete identification of the errors. Meanwhile, as the error is increased when position departure increasing, an iterative solution method is taken to restrain the influence of the error brought by the mechanism. The algorithm is simple in principle, easy to realize, and has high calibration accuracy. It can be used to calibrate all the 21 error parameters of the inertial instruments without high-precision test equipments. The mathematical simulation and the experiment have proved it meets requirements of navigation with high practical value in engineering.