A CONSIDERATION ON THE EXTRAORDINARY RESPONSE OF THE AUTOMATIC STEERING SYSTEM FOR SHIP MODEL IN QUARTERING SEAS

In the Seakeeping Model Basin of the Ship Research Institute, an automatic steering system for ship model is used to keep its course in waves. Basically this system is a continuous PD control for the heading angle deviation, and it was experimentally designed to have satisfactory response characteristics both in calm water and in waves. Occasionally unexpected long period response of the steering system was observed in the quartering or following sea condition. This response is not preferable to perform more accurate measurement. It is also important practically, because similar response of an actual ocean going ship has been reported. In the present paper, the mechanism of the response has been investigated. By the results of analogue computer simulation, the cause of the response has become evident. Because of the non-linear elements of the system, i.e. saturation in steering velocity and rudder angle limitation, the response whose period is longer than encounter period is possible to be excited by waves. To prevent the unpreferable response, some comments and specifications for the automatic steering system of the ship model are shown.

  • Supplemental Notes:
    • Xerox copies of paper available from MRIS for $4.75.
  • Corporate Authors:

    Ship Research Institute, Tokyo

    38-1, 6-chome, Shinkawa, Mitaka-shi
    Tokyo,   Japan 
  • Authors:
    • Fuwa, T
  • Publication Date: 1976-11

Media Info

  • Features: References;
  • Pagination: 15 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00152592
  • Record Type: Publication
  • Report/Paper Numbers: No. 50
  • Files: TRIS
  • Created Date: May 31 1977 12:00AM