Guidance precision factors of terminal correction mortar projectile using pulse jets

Trajectory sag due to gravity and demodulation error caused by roll angle measurement error are the main factors that influence the guidance precision of Terminal Correction Mortar Projectile (following called TCMP for short) using pulse jets. TCMP dynamics model and guidance loop model are established, and then the impact of pulse jet impulse, pulse jet ignition waiting time and gravity on the guidance loop is obtained via analyzing phase trajectory of TCMP position deviation. According to the discrete control characteristics of impulse force, we propose bias threshold method for gravity compensation. The quantitative relationship between pulse jet firing waiting angle and roll angle measurement error is derived under gravity compensation. Moreover, roll coupling guidance loop simulation model of TCMP is established, and then the model is simulated under different waiting angle demodulation error. Simulation results show that TCMP has a certain tolerance to roll angle measurement error.