Research On Roll Attitude Measurement And ADRC System Of Guided Projectile

In modern and information warfare,guided projectiles have received extensive attention from countries around the world due to their advantages of high combat effectiveness,good damage effect,small collateral damage,and low cost.In this paper,experiments are mainly carried out on a low-rotation projectile with two pairs of duck-shaped surfaces.The development of this guided ammunition is discussed from two aspects of theory and technology,the real-time attitude measurement,aerodynamic parameter identification and control system design are studied.Firstly,according to the aerodynamic and motion characteristics of the canard layout guided projectile,the relevant coordinate system is defined,and the six degree of freedom flight dynamics model is established.According to the requirements of different applications,the aerodynamic model and the attitude control model considering the coupled effects of different channels are proposed.Secondly,the problems related to the real-time roll attitude measurement of guided projectiles based on geomagnetism are studied.In order to correct the error of the missile-borne magnetic measurement,a geomagnetic measurement error model including the sensor system error and the soft and hard magnetic interference of the missile body is established by analyzing the source of the error,and a real-time correction method of the magnetic sensor based on adaptive parameter estimation is proposed.Aiming at the problem that the geomagnetic measurement signal is easily affected by various random interference noises,a noise suppression method based on threshold filtering based on complete empirical mode decomposition is proposed.Simulation results show that the method can effectively remove all kinds of pulse interference and suppress the noise in the signal.On this basis,a roll angle attitude estimation algorithm based on adaptive Kalman filter is proposed.Simulation and experimental results verify that the algorithm has relatively good stability and measurement accuracy.Then,the related problems of aerodynamic parameter identification of guided projectiles are studied.In order to fully excite the motion mode of the guided projectile,a particle swarm algorithm is proposed to optimize the design of the multi-sine excitation input signal,and the simulation results show that the parameter identification accuracy is improved by using the input as the excitation.Aiming at the problems of complex sensitivity formula derivation and sensitive initial value in the traditional maximum likelihood criterion parameter identification algorithm,an improved chaotic adaptive particle swarm optimization algorithm is proposed.The algorithm introduces chaos optimization and improves the traversal of particle search.The improved chaotic adaptive particle swarm optimization algorithm has better identification performance than the basic particle swarm optimization algorithm.Finally,considering the coupled effect between the pitch and yaw channels of low-spin guided projectiles,firstly,the coupling characteristics of motion and control of the spin missile are summarized.Then,an attitude control method based on hybrid active disturbance rejection is proposed,which combines the advantages of linear and nonlinear active disturbance rejection control,and solves the problem of parameter setting of nonlinear active disturbance rejection control and large observation error under large disturbance.Different switching control strategies are selected according to the error dynamic characteristics of each loop of attitude control,which can reduce the influence of strong disturbances on attitude control under dynamic conditions.The simulation results show that the control method can meet attitude control requirements of the high-precision and strong robustness of low-spin guided projectiles.