Ballistic boost phase guidance using nominal effort miss steering

Based on the concept of nominal effort miss (NEM), a guidance law for boost phase is proposed to handle the situation when the solid rocket motor in the tactical missile must be used up. On the foundation of zero effort miss (ZEM), NEM is defined and the differences between them are compared. By means of the trajectory prediction and the property of NEM, a calculation approach to NEM is derived. In combination with the relative movement between the missile and the target, the linear dynamic equation is presented. Finally, according to these equations, the guidance law is obtained. Though the guidance law designed in this paper is dependent on the reference trajectory, there is no need to control the shutdown time and it can be applied to boost phase control in the ballistic missile system. Simulation results demonstrate that when there are wind disturbance and thrust error and drag error, the guidance law can effectively correct the missile flight trajectory and reduce the miss distance to a suitable range.