Improved method of restraining taper error in GFSINS

The taper error exists with new character in Gyroscope-free Strap-down Inertial Navigation System. For GFSINS can´t give out angle increment directly when adopting Equivalent Rotation Vector Algorithm with four samples, new calculating method was designed and optimized to improve the efficiency of attitude refreshing. At last, the coefficient in the calculating formula of equivalent rotation vector was optimized by Chaos Particle Swarm Optimization Algorithm. The simulation result showed that it could eliminate the influence of taper error effectively and improve the navigation precision.