Technique for determining roll attitude of spin-stabilized projectiles based on third-order phase-locking loops

An analysis of spin-stabilized projectile angular motion characteristics was performed to determine the roll attitude of a spin-stabilized projectile using a low-range gyroscope. A mathematical model was established, and a method of determining the roll attitude of the spin-stabilized projectile using a low-range gyroscope was proposed based on third-order phase-locking loops. A loop filter parameter of the third-order phase-locking loops was calculated using the characteristics of the spin-stabilized projectile coupled with an angular motion signal and measured signal of the low-range gyroscope. Moreover, the roll angle and angular roll rate can be calculated using the proposed methodology. Experimental results show that the proposed method can effectively lock the angular roll motion signal of the spin-stabilized projectile and calculate the roll attitude of that spin projectile with a high degree of accuracy.