Improved Optimal Terminal Guidance Law Based on Virtual Expected Terminal Impact Angle

Abstract

To reduce the overload magnitude on the terminal guidance stage with a large terminal impact angle constraint, this paper proposes an improved optimal terminal guidance (IOTG) law. A time-varying virtual expected terminal impact angle is introduced, which can solve the problem that the required overload is high especially in the initial stage. Meanwhile, by analyzing the relative motion model between the vehicle and the target with the proposed guidance law, the terminal impact angle will reach the expected state in finite-time. The proposed adaptive parameters adjustment rule is suitable for different initial relative distances between the vehicles and targets. Simulation results demonstrate that the vehicle can reach the target in a large terminal impact angle. Compared with the optimal terminal guidance (OTG) law, the maximum overload magnitude with IOTG is reduced by 41.22%, which increases the safety of the vehicle.