On the Application of Modern Control Theory to Ship Roll Stabilisation,
Abstract
The high feedback gains employed by current active roll stabilisation systems result in control surface cavitation and excessive machinery activity, both of which contribute significantly to the noise radiated by the ship. In the case of warships, this noise is most undesirable. To circumvent this difficulty, a reduced noise mode of operation is proposed for use in a threat situation. This reduced noise mode is characterised by little or no cavitation and low levels of machinery wear. A design procedure incorporating modern control theory as the major tool in the selection of feedback gains for ship roll stabilisation is presented. The procedure is applied to the reduced noise mode, but may be readily adapted to controller design for other modes of operation. With this technique, the designer is able to minimise a performance index which is a function of both roll angle and fin angle, while keeping fin motions below the cavitation limit. Application to an example ship configuration employing fin, rudder or combined fin-rudder control is considered. The closed loop performance of these systems is simulated and the results demonstrate the power of modern control theory in this application. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1979
- Accession Number
- ADA072717
Entities
People
- P. H. Whyte
Organizations
- Defence Research and Development Canada