Research On The Strapdown Inertial Navigation System Algorithms Based On Dual Quaternions

Strapdown inertial navigation technology has been widely used in military and national production. However, the accuracy of strapdown inertial navigation system (SINS) in our country is still low nowadays. Most SINS were used in low accuracy vehicles under low speed condition. To settle this problem, one way is to design and make high precision inertial instruments, to get more accurate information of the motion state. But the inertial instruments' performances are limited with material and technical level. Also,it's important to build the system error model precisely. System error compensation methods should be studied. Another way is to design and use optimal algorithms. Thus, it is very important to study high precision algorithms for SINS.In this paper, conventional algorithms for SINS are studied. Also, a new SINS algorithm based on dual quaternions is designed. 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. Then, it is discussed that the optimized attitude algorithms and corrected attitude algorithms which are derived from the former. The velocity algorithms in SINS are also deduced.2. The design of SINS algorithms based on dual quaternions is addressed. The principle of strapdown inertial navigation is represented using the tool of dual quaternion. It is shown that the principle can be expressed by three continuous kinematic equations in dual quaternion. It is proved that the strapdown navigation equations in dual quaternion are theoretically consistent with the conventional ones. Then, analytic comparisons between the new algorithm and the conventional ones are carried out in various aspects.3. A variety of simulations are carried out to support the analytic results with Matlab/Simulink. The analysis shows that the new algorithm is promising in accuracy and in coping with vehicle maneuvers with more robustness. Several...