Impact angle constrained terminal guidance based on continuous nonsmooth control method

Three-dimensional terminal guidance law design problem of flight vehicle with terminal impact angle constraints is investigated in the paper. In order to improve the control performance of precision guided weapon in dive phase, a nonlinear guidance law with finite time convergence and terminal impact angle constrains is derived with non smooth control approach. Based on three-dimensional design model, we set the trajectory slope angle rate and trajectory azimuth angle rate as the control variables to design guidance law. Compared to proportional navigation guidance law, the proposed guidance law can make the vehicle satisfy the impact angle constrains, besides it improves the convergent rate of system states that makes the vehicle have shorter flight time and better terminal accuracy.