Ship motion,with six degrees of freedom,is a complex stochastic process.Sea wind and waves are the primary influencing factors.Prediction of ship motion is significant for ship navigation.To eliminate errors,a path pr...Ship motion,with six degrees of freedom,is a complex stochastic process.Sea wind and waves are the primary influencing factors.Prediction of ship motion is significant for ship navigation.To eliminate errors,a path prediction model incorporating ship pitching was developed using the Gray topological method,after analyzing ship pitching motions.With the help of simple introduction to Gray system theory,we selected a group of threshold values.Based on an analysis of ship pitch angle sequences over 40 second intervals,a Grey metabolism GM(1,1) model was established according to the time-series which every threshold corresponded to.Forecasting future ship motion with the GM(1,1) model allowed drawing of the forecast curve with effective forecasting points.The precision of the test results show that the model is accurate,and the forecast results are reliable.展开更多
With the rapid development of the shipping industry,the safety and comfort of ship transportation have been paid more and more attention,and the pitch and heave motion of ships are the most serious factors.In this pap...With the rapid development of the shipping industry,the safety and comfort of ship transportation have been paid more and more attention,and the pitch and heave motion of ships are the most serious factors.In this paper,the longitudinal motion mathematical model of YuKun is esta b lished.By assigning the zero-pole to the left half-plane and using the properties of the symmetric matrix,the shaping weighting functions matrix is designed to stabilize the multi-input multi-output(MIMO)system of YuKun.Finally,a new concise robust controller is designed using the steady output of the shaped system.The simulation results show that under the control of the concise robust controller,the pitch angle and heave of YuKun decrease by 79.9% and 86.2%,respectively.Theoretical analysis and simulation results show that the concise robust controller has a good control effect on the longitudinal motion of YuKun,and is simple and easy to use,with clear engineering significance.展开更多
文摘Ship motion,with six degrees of freedom,is a complex stochastic process.Sea wind and waves are the primary influencing factors.Prediction of ship motion is significant for ship navigation.To eliminate errors,a path prediction model incorporating ship pitching was developed using the Gray topological method,after analyzing ship pitching motions.With the help of simple introduction to Gray system theory,we selected a group of threshold values.Based on an analysis of ship pitch angle sequences over 40 second intervals,a Grey metabolism GM(1,1) model was established according to the time-series which every threshold corresponded to.Forecasting future ship motion with the GM(1,1) model allowed drawing of the forecast curve with effective forecasting points.The precision of the test results show that the model is accurate,and the forecast results are reliable.
基金This work is partially supported by the National Science Foundation of China(Grant No.51679024)Dalian Innovation TeamSupport Plan in the Key Research Field(Grant No.2020RT08)The Funda mental Research Funds for the Central Universities(Grant No.3132021139)。
文摘With the rapid development of the shipping industry,the safety and comfort of ship transportation have been paid more and more attention,and the pitch and heave motion of ships are the most serious factors.In this paper,the longitudinal motion mathematical model of YuKun is esta b lished.By assigning the zero-pole to the left half-plane and using the properties of the symmetric matrix,the shaping weighting functions matrix is designed to stabilize the multi-input multi-output(MIMO)system of YuKun.Finally,a new concise robust controller is designed using the steady output of the shaped system.The simulation results show that under the control of the concise robust controller,the pitch angle and heave of YuKun decrease by 79.9% and 86.2%,respectively.Theoretical analysis and simulation results show that the concise robust controller has a good control effect on the longitudinal motion of YuKun,and is simple and easy to use,with clear engineering significance.
