The invention provides a ship track active-disturbance-rejection control method based on the slip form of a multi-
modal nonsingular terminal. The method includes the steps of constructing an expectedship heading equation according to navigational parameters of a ship, deducing a
discretization nonlinear structural model of a two-order
differentiator,
processing expected ship heading signals in the expected ship heading equation to obtain expected ship heading differential signals required for controlling the
rudder angle by the control law, obtaining the output
rudder angle on the basis of the switchable
error feedback control law, constructing an expanded
state observer in combination with the
error feedback control law, tracking the output deviation according to the expanded
state observer, estimating the heading angle and inner and outer disturbance errors controlled by the control law, and feeding the heading angle and the inner and outer disturbance errors back into the control law. By improving the expanded
state observer, a linear function and a nonlinear function can be switched in real time; the switchable segmented slip form face is designed; through the segmented slip form face, the switchable
error feedback control law is designed, and the under-actuated ship track control is well realized.