Application of modified Rodrigues parameters for spinning projectiles

The fiber optic gyro(FOG) can be used on the navigation of the spinning projectiles. And one of the most important means is the strap-down inertial navigation system (SINS) based on FOG, while the attitude updating algorithm is the core of SINS. According to the characteristics of short flight time and close rang of fire, an allattitude determination algorithm based on modified Rodrigues parameters(MRPs) is designed, and a mathematical model is given for the attitude measurement of spinning projectiles. Compared with the common attitude updating algorithm, the simulation results indicate that the new algorithm can suppress the non-commutable error effectively, reduce the accumulative error over time, save the computation in high dynamic environment, and improve the navigation speed and accuracy.