Research On Guidance Laws Of Impact Time Consensus For Multi-Missiles

Multi-missile cooperative guidance can effectively improve the penetration and strike effect of missile group,which is a hot and difficult problem in the field of missile guidance.In this paper,aiming at the guidance problem of multi-missile cooperative strike against fixed targets,firstly,the time-to-go estimation method of missile strike against fixed targets is analyzed;then,the guidance law of single missile impact time constraint is studied;then,the multi-missile cooperative guidance law that coordinates the impact time of missile groups tends to be consistent is studied;finally,a multi-missile cooperative strike simulation system is built based on a cruise missile model,and the effectiveness of the proposed cooperative guidance law is verified by numerical simulation.The main achievements of this paper are as follows:Based on the exact series solution of missile’s time-to-go,two typical single missile impact-time-control guidance laws are improved.In-depth study and comparative analysis of existing time-to-go estimation methods of missile,one of the series solutions with the highest accuracy is selected,and it is substituted into the cooperative proportional navigation(CPN)law and the optimal impact-time-control guidance(OITCG)law based on the optimality error dynamics.The improved CPN(ICPN)and improved OITCG(IOITCG)can effectively improve the impact-time-control accuracy and reduce the maximum instruction overload of the guidance law.Based on the controller with free time convergence,an new impact-time-control guidance law of single missile with free time convergence is proposed.ICPN and IOITCG can only ensure that the impact time error of missile converges to zero gradually when the missile hits the target.Based on the free time convergence controller and the exact series solution of time-to-go,this paper designs a new free time convergent impacttime-control guidance(FTCITCG)law.The guidance law has the characteristics of concise form,less required guidance parameters and clear physical meaning,which can make the missile impact time error converge to zero within a set time,and the guidance law converges to pure proportional guidance law(PPN)at the same time.The guidance law has strong application potential.Based on FTCITCG,considering the communication topology between missiles,a free time convergent cooperative guidance law is designed.In this paper,based on the newly proposed FTCITCG,a cooperative guidance law with free time convergence for multiple missiles is designed,considering two kinds of communication topologies between missiles,i.e.,fully connected and not fully connected,and selecting the maximum time to go of missiles as a coordination variable,and its asymptotic convergence and free time convergence are strictly proved.Finally,based on a cruise missile model,considering the fine earth model and atmospheric model,a pseudo-six-degree-of-freedom simulation system for multi-missile cooperative strike is constructed,and the performance of the proposed cooperative guidance law is verified by numerical simulation for the fully connected and non-fully connected missile group communication topology.Aiming at the singularity and robustness problems that may occur in the practical application of cooperative guidance law,the strategies of de-singularity and threshold control are designed.Simulation results show that the multi-missile cooperative guidance law designed in this paper has good practicability and reliability.