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Simulering av styrsystem för tankfartyg

Aspernäs, Bertil and Foisack, Per (1975) In MSc Theses
Department of Automatic Control
Abstract
The main purpose of this investigation was to compare, by simulations, the ability of an adaptive regulator and a PID-regulator to keep a ship on desired course with small rudder deflections. Manual steering in confined waters of the simulated ship was also performed. Recordings of delivery tests from real ships were compared to simulations. The non-linear mathematical model of the ship, which was used in the simulations, describes the motion in the horizontal plane. The values of the model parameters are estimated for a 255 000 dwt tanker. Stochastic disturbances to describe the influence of wind and waves were also introduced in the ship model. The adaptive regulator performs a least squares estimation of the parameters in a controller... (More)
The main purpose of this investigation was to compare, by simulations, the ability of an adaptive regulator and a PID-regulator to keep a ship on desired course with small rudder deflections. Manual steering in confined waters of the simulated ship was also performed. Recordings of delivery tests from real ships were compared to simulations. The non-linear mathematical model of the ship, which was used in the simulations, describes the motion in the horizontal plane. The values of the model parameters are estimated for a 255 000 dwt tanker. Stochastic disturbances to describe the influence of wind and waves were also introduced in the ship model. The adaptive regulator performs a least squares estimation of the parameters in a controller which minimizes the variance of the course error. This regulator gave smaller course errors but larger rudder deviations than a well tuned PID-regulator. The large advantage of the adaptive regulator compared to the PID-regulator is that no manual tuning of parameters for different speeds, loading conditions and weather types is necessary. The manual tuning of the parameters of a PID-regulator has sometimes proved to be difficult to perform on real ships. A conceivable development of the adaptive regulator, which is tested in this report, is to consider the ridder deviations too, when the control is computed. (Less)
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author
Aspernäs, Bertil and Foisack, Per
supervisor
organization
year
type
H3 - Professional qualifications (4 Years - )
subject
publication/series
MSc Theses
report number
TFRT-5154
ISSN
0346-5500
language
Swedish
id
8850352
date added to LUP
2016-03-29 10:22:52
date last changed
2016-03-29 10:22:52
@misc{8850352,
  abstract     = {The main purpose of this investigation was to compare, by simulations, the ability of an adaptive regulator and a PID-regulator to keep a ship on desired course with small rudder deflections. Manual steering in confined waters of the simulated ship was also performed. Recordings of delivery tests from real ships were compared to simulations. The non-linear mathematical model of the ship, which was used in the simulations, describes the motion in the horizontal plane. The values of the model parameters are estimated for a 255 000 dwt tanker. Stochastic disturbances to describe the influence of wind and waves were also introduced in the ship model. The adaptive regulator performs a least squares estimation of the parameters in a controller which minimizes the variance of the course error. This regulator gave smaller course errors but larger rudder deviations than a well tuned PID-regulator. The large advantage of the adaptive regulator compared to the PID-regulator is that no manual tuning of parameters for different speeds, loading conditions and weather types is necessary. The manual tuning of the parameters of a PID-regulator has sometimes proved to be difficult to perform on real ships. A conceivable development of the adaptive regulator, which is tested in this report, is to consider the ridder deviations too, when the control is computed.},
  author       = {Aspernäs, Bertil and Foisack, Per},
  issn         = {0346-5500},
  language     = {swe},
  note         = {Student Paper},
  series       = {MSc Theses},
  title        = {Simulering av styrsystem för tankfartyg},
  year         = {1975},
}