Nonsingular terminal sliding mode guidance law of impact time and impact angle control

Abstract:

To improve the penetration ability of missiles and enhance the damage effect, the problems of impact time and impact angle control of missiles were studied. A nonsingular sliding mode guidance law was proposed based on the relative dynamics of missile and target. According to the shaping theory, a line-of-sight (LOS) polynomial satisfying impact time and impact angle constraints simultaneously was designed. The coefficient was determined using an optimization method. Since the nonsingular terminal sliding mode theory has the characteristic of fast convergence of sliding surface in finite time, a sliding surface was constructed via the error of the LOS, and a nonsingular impact time and impact angle control guidance law was designed. The proposed guidance law could change the actual LOS according to the designed LOS to satisfy the constraints of impact time and impact angle. Through theoretical analysis, it was proved that the proposed guidance law satisfied the Lyapunov stability criterion and could realize the control of the impact time and impact angle without singularities. The proposed guidance law was numerically simulated in different situations. Numerical simulation results show that the proposed guidance law could control impact time and impact angle effectively under various conditions and had certain advantages compared with existing literature. Even with a certain degree of external interference, the impact time and impact angle control could still be completed.