Fractional Order Differential Sliding Mode Guidance Law with Impact Angle Constraint

In this paper, a fractional order sliding mode guidance law to stationary targets is proposed which can also achieve impact angle constraint. A new independent variable is introduced. The sliding surface is well analyzed by both Lyapunov stability and analytical expressions. The fractional order term and initializing term affect the variations of the sliding surface, flight path angle and trajectory. Regulations are summarized according to the guidance expectations. By setting parameters properly, the fractional order guidance law has further hit downrange compared with the integer one. The extension of hit downrange can be applied in practical engineering. The proposed guidance law shows good effectiveness and robustness.