METHOD OF SHIP AUTOMATIC CONTROL IN ROUGH SEA Russian patent published in 2013 - IPC B63H25/04 

FIELD: transport.

SUBSTANCE: invention relates to navigation in preset route. Proposed method proceeds from automatic ship control with the help of two control laws, i.e. optimum (in terms of ship stabilisation accuracy in quiet sea) and light duty control (for preservation of steering drive serviceability in rough sea). Selection of said control modes is effected automatically owing to application of control factor changeover unit that generates two terms of control law selection. In compliance with first term, signal of mean magnitude of rudder angle modulus exceeds tolerable magnitude while signal of mean magnitude of roll angle modulus exceeds tolerable magnitude. In compliance with second term, signal of mean magnitude of rudder angle modulus is smaller than tolerable magnitude while signal of mean magnitude of roll angle modulus is smaller than tolerable magnitude. In observance of said first term, light duty control law is generated. In observance of second term, optimum control law is generated.

EFFECT: optimised rudder control with due allowance for roll and rudder drive load.

1 dwg