Guidance Simulation and Experimental Verification of Trajectory Correction Mortar Projectile

Integrated methods are used in the modification of trajectory, including improved perturbation impact point deviation prediction, adaptive proportional guidance and adaptive proportional differential guidance, thus improving the firing accuracy of guided mortar shell. The six degrees of freedom of both the trajectory model and the control model were established, and their guidance laws were designed based on the three guidance schemes. Firstly, the perturbation impact point deviation prediction method is improved by setting up a discrimination factor in the rising phase of trajectory based on the principle of traditional perturbation impact point deviation prediction method and in combination with the trajectory characteristics of guided mortar, which further improves the correction efficiency. The adaptive proportional guidance law is designed in the longitudinal plane, while the adaptive proportional differential guidance law is designed in the transverse plane due to the fact that the constant proportional coefficient in the proportional guidance law does not conform to the requirements of actual trajectory. In this paper, Monte Carlo simulation method and ammunition flight test are used to verify the designed guidance law, and the simulation results illustrate that the integrated guidance method is both reasonable and effective. As for the error of the guidance tool and actuator, the method is available for the reduction of impact point deviation and the improvement of accuracy. The circular error probability (CEP) not under control decreases from 126.317m to 10.1284m when control is applied. Besides, the feasibility of the designed guidance law is verified by the flight tests of guided mortar projectile in large, medium and small range respectively from the perspective of engineering application. It can be seen from the test trajectory impact point data that the guidance law is available for the effective correction of trajectory deviation in the actual hardware operation and site environment with reliable guidance. As the outcome, the CEP reaches 10.86m, and the impact point deviation of some guided missiles is within 2m.