The application of integral filter in guided projectile to determine the initial roll angle

For inertial guidance system, which uses the gyros output to identify the roll angle, the alignment accuracy of the roll angle depends on the accuracy of the gyros output. In order to eliminate the gyros biases and noise effect, the integral filter equations were derived according to the characteristics of low-speed roll guided projectile initial flight segment. The results of simulation experiments show: the integral filter is able to accurately estimate the biases of gyros and eliminate the noise; the data filtered by integral filter can meet the accuracy requirement for determining the initial roll angle. Obviously, the integral filter is better than traditional Butterworth low-pass filter.