Study On High-accuracy Algorithms In The SINS

Strapdown inertial navigation system (SINS) is a kind of advanced inertial navigation technology, and it is the developing direction of inertial navigation. For SINS has a series of advantages, it has become a trend that SINS will take the place of platform inertial navigation system in new century. Nowadays, the accuracy level of SINS in our country is still low. To settle this problem, One day is to design and make high precision inertial instruments, i.e. gyros and accelerometers. But the inertial instruments' performs are limited with material and technical level. Another way is to design and use optimal algorithms. Thus, it is necessary to study the high precision algorithms for SINS. In the paper, the following works have been done:1. It is introduced that the basic operation principle of SINS, including several kinds of coordinates and the relations between them, classical attitude algorithms of Euler horn and quaternion, and the accounting cycle etc .2. It is discussed that the optimized attitude algorithms and corrected attitude algorithms which are derived from the former. Then those are analyzed and emulated in Matlab. And we give some study on getting corner velocity from corner increment.3. It is deduced that the velocity algorithms in SINS. And we often get them on opposite with the attitude algorithm on rotation vector.4. It is discussed that the system error and dynamic error, especially the dynamic error in position algorithm.