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1.
A novel type of control law was adopted to reduce the vertical acceleration of a fast ferry as well as the motion sickness incidence suffered by the passengers onboard by means of a submerged T-foil. Considering the system changing characteristics under high disturbances, a model-free approach was adopted. In addition, an upgraded proportional-derivative(PD) controller with correction terms resulting from a fast-online estimation of the system dynamics was designed. The overall controller, known as intelligent PD(i-PD) controller, was tested, and the obtained results were compared with those of a classic PD controller. The controllers were also tested in a changing environment and at different operating velocities. The results confirmed the effectiveness of the i-PD controller to smooth the motions with low computational cost control schemes. Furthermore, thanks to ability of the i-PD controller to continually update the estimated dynamics of the system, it showed a better reduction in both vertical motions and the seasickness level of the passengers with the needed robustness under external disturbances and system changing parameters.  相似文献   

2.
This paper mainly focuses on the heading control of a position-moored vessel operating under level ice regime. A dynamic ice simulator interconnecting the vessel motions with the ice dynamics is used for the design of the heading control system. The strategy is to ensure that the vessel is kept at an appropriate position within the safe limits. Using a heading controller based on a Kalman filter, the desired control force is computed to counteract the environmental disturbances. A thrust allocation method is developed to go with the heading controller. To keep the ice forces to a reasonable level, the moored vessel should be aligned with the ice drift direction and small angles up to 15° in changes on heading against the ice flow could be possible. Therefore, heading control of a moored vessel exposed to level ice with drift angle 0° and 15° is simulated since the dynamic positioning system needs to resist ice yaw moments and lateral ice forces on the hull. The simulation indicates that the proposed control strategy performs satisfactorily for a moored vessel in level ice.  相似文献   

3.
张玉芳  刘长德 《船舶工程》2020,42(12):79-84
针对船舶动力定位系统模型受到风浪流等环境未知有界扰动的问题,提出一种基于干扰估计补偿的反步控制算法。首先基于滑模面有限时间收敛特点设计干扰观测器,在有限时间内实现对未知有界干扰的估计,并采用一阶低通滤波器连续化干扰观测器估计值,减少抖振;然后基于干扰观测器设计船舶动力定位反步控制器,并应用Lyapunov函数证明了所设计的控制器使船舶的位置和航向收敛于期望值。最后通过铺缆船仿真结果表明所设计控制器具有较好的控制性能,对系统的有界干扰具有良好的鲁棒性。  相似文献   

4.
以荷兰某公司设计的波浪控制平台为研究对象,对其主要的液压元件添加传递函数,并建立电液伺服控制系统传递函数方块图。然后通过 AMESIM 仿真平台建立液压系统模型,探索在不同伺服增益参数时系统的动态误差。仿真结果显示,只通过改变伺服增益,系统不能满足实际精度要求。为此,本文在控制系统中采用 PD 控制算法,借助 AMEsim 中的遗传算法进行优化,得到最优 Kp 和 Kd 参数。结果表明,此方法能使系统实现所需精度及稳定性要求。  相似文献   

5.
动力定位控制系统在实际工况中会受到外部风、浪、流等环境力的扰动,本文主要研究PD+RBF控制算法以提高动力定位系统的抗干扰性和稳定性.RBF神经网络用来补偿外界环境扰动,其权值自适应律通过Lyapunov稳定性证明得到,通过稳定性的分析能够保证整个系统全局渐进稳定.在一艘平台供应船的仿真结果对比中显示了所提出控制器的有效性.  相似文献   

6.
The flow noise associated with sinusoidal vertical motion of a sonobuoy restrains its working performance.In practice,a suspension system consisting of elastic suspension cable and isolation mass is adopted to isolate the hydrophone from large vertical motions of the buoy on the ocean surface.In the present study,a theoretical model of vertical motion based on the sonobuoy suspension system was proposed.The vertical motion velocity response of the hydrophone of a sonobuoy can be obtained by solving the theoretical model with Runge-Kutta algorithm.The flow noise of the hydrophone at this response motion velocity was predicted using a hybrid computational fluid dynamics(CFD)-Ffowcs Williams-Hawkings(FW-H) technique.The simulation results revealed that adding the elastic suspension cable with an appropriate elastic constant and counterweight with an appropriate mass have a good effect on reducing the flow noise caused by the sonobuoy vertical motion.The validation of this hybrid computational method used for reliable prediction of flow noise was also carried out on the basis of experimental data and empirical formula.The finds of this study can supply the deep understandings of the relationships between flow noise reduction and sonobuoy optimization.  相似文献   

7.
针对小水线面双体(SWATH)船运动控制问题,设计了带有扩张状态观测器(Extended State Observer, ESO)的终端滑模控制器。首先,针对SWATH船在随机海浪作用下的运动问题,建立了带有系统复合扰动的非线性运动模型;进而,考虑到系统存在的参数摄动和海浪扰动的复杂性、随机性,将系统分为内环观测器和外环控制器分别设计;利用一个线性ESO对系统的复合扰动进行估计,并在外环终端滑模控制器中进行补偿;最后,利用Lyapunov理论得到了系统的渐进稳定结论。仿真结果表明,带有ESO的终端滑模控制方法能够有效实现SWATH船的运动控制,线性ESO能够准确估计出系统的复合扰动,且终端滑模控制器能够使系统状态快速收敛。  相似文献   

8.
基于Bech模型的船舶航向自抗扰控制器设计与仿真   总被引:1,自引:1,他引:0  
基于船舶非线性Bech模型提出了一种新型船舶航向控制器——高阶自抗抗控制器(ADRC),该控制器主要由三阶TD、四阶ESO和非线性状态误差反馈(NLSEF)三部分组成.设计扩张状态观测器时,采用二阶TD的滤波功能对系统输出进行噪声滤波,并用其滤波值来建立扩张状态观测器.通过航向改变、参数摄动、外界干扰的仿真试验表明,自抗扰控制器控制效果良好,具有较强的鲁棒性.  相似文献   

9.
张玉芳  刘长德  张凤伟  王志鹏 《船舶力学》2016,20(12):1547-1556
装配动力定位系统的浮式结构物由于受到风、浪、流等交变载荷影响,其运动具有明显时滞和非线性特性,为克服传统控制策略抗干扰能力差对动力定位控制性能的影响,文章基于反步法,对动力定位系统进行了控制器设计研究,针对波浪及流外载荷形成的有界干扰问题,采用自适应策略进行估计补偿。并借助Lyapunov理论分析了闭环系统的稳定性。最后以某深水半潜平台为对象,对其不同工况下动力定位作业进行了数值计算研究,验证了所设计控制器具有良好的鲁棒性,可为后续动力定位模型试验及实船控制器设计提供理论支撑。  相似文献   

10.
Given the uncertainty of parameters and the random nature of disturbances that effect a ships course, a robust course controller should be designed on the basis of rudder/flap vector control. This paper analyzes system uncertainty, and the choice of weighting functions is also discussed. When sea waves operate on a ship, the energy-concentrating frequency varies with the angle of encounter. For different angles of encounter, different weighting functions are designed. For the pole of a nominal model existing in an imaginary axis, the bilinear-transform method is used. The "2-Riccati" equation is adopted to solve the H∞ controller. A system simulation is given, and the results show that, compared with a PID controller, this system has higher course precision and more robust performance. This research has significant engineering value.  相似文献   

11.
采用MMG分离式船舶运动数学模型以及拖缆的悬链线模型,构建了由拖船——拖缆——被拖船组成的拖航系统操纵运动模型。通过数值计算,对该系统进行了操纵运动模拟仿真。主要的仿真项目包括拖航系统改变航向和受到小扰动时的运动。在此基础上研究了影响拖航系统航行性能的诸多因素,这些因素主要有:拖缆的长度、拖航速度、被拖船的拖航点位置。针对浅水效应给予拖航系统的影响以及通过改变PD控制参数改善拖航系统航向稳定性进行的初步探讨,得到了一系列有益的结论。  相似文献   

12.
基于解析模型预测控制的欠驱动船舶路径跟踪控制器设计   总被引:3,自引:0,他引:3  
针对欠驱动船舶路径跟踪控制系统中存在风、浪、流等外界干扰的影响,将船舶运动模型转化到Serret-Frenet标架下进行研究,通过引入重定义输出将原单输入多输出控制系统转化为单输入单输出控制系统,并将解析模型预测控制与非线性观测器相结合,提出一种鲁棒路径跟踪控制算法。该算法能够使欠驱动船舶跟踪并镇定于给定的参考路径。计算机仿真结果表明,所提出的控制器具有良好的控制性能以及鲁棒性能。  相似文献   

13.
To provide a suitable model for AUV simulation and control purposes, a general nonlinear dynamic model including a novel thruster hydrodynamics model was derived. Based on the modeling method, the “AUV-XX” simulation platform was established to carry out fundamental tests on its motion characteristics, stability, and controllability. A motion control strategy consisting of both position and speed control in a horizontal plane was designed for different task assignments of underwater vehicles. Combined control of heave and pitch was adopted to compensate for the reduction of vertical tunnel thrusters when the vehicle is moving at a high speed. An improved S-surface controller based on the capacitor plate model was developed with flexible gain selections made possible by different forms of restricting the error and changing the rate of the error. Simulation results show that the derived general mathematical model together with simulation platform can provide a test bed for fundamental tests of motion control. Additionally, the capacitor plate model S-surface control shows a good performance in guiding the vehicle to achieve the desired position and speed with sufficient accuracy.  相似文献   

14.
Given the uncertainty of parameters and the random nature of disturbances that effect a ships course, a robust course controller should be designed on the basis of rudder/flap vector control. This paper analyzes system uncertainty, and the choice of weighting functions is also discussed. When sea waves operate on a ship, the energy-concentrating frequency varies with the angle of encounter. For different angles of encounter, different weighting functions are designed. For the pole of a nominal model existing in an imaginary axis, the bilinear-transform method is used. The "2-Riccati" equation is adopted to solve the H∞ controller. A system simulation is given, and the results show that, compared with a PID controller, this system has higher course precision and more robust performance. This research has significant engineering value.  相似文献   

15.
为实现水下航行器高效稳定运行,将对转永磁同步电动机应用到对转螺旋桨推进系统中,不仅能够简化推进系统结构、减小体积、降低重量和成本,而且没有电刷滑环,运行更加安全可靠.本文模拟双转子在推进器不同扰动情况,观察电流、转速和转矩响应.针对双转子永磁电机的转速控制精度不高和解决两边转子带不平衡负载时转矩扰动问题,设计一种积分型滑模变结构控制器.该仿真结果表明,控制器使系统具有快速性和精确性且对负载扰动具有较强的鲁棒性.  相似文献   

16.
水下自主航行器在近水面航行中存在着深度跟踪和姿态控制较为困难的问题。为此,首先建立了自主航行器的近水面三自由度运动数学模型,然后设计了无迹卡尔曼滤波器实现对系统状态的估计;接着,利用斯特林内插法在变动的工作点处对自主航行器模型进行近似线性化,并根据线性化后的模型设计预测控制器,实现自主航行器的变深运动控制。经过仿真实验,验证了滤波器对自主航行器近水面运动状态估计的准确性以及预测控制器在抗海浪扰动上的控制效果。仿真结果表明,带有无迹卡尔曼滤波器的预测控制器可以快速、准确的实现自主航行器的深度跟踪控制与姿态控制,且具有响应速度快,对外部扰动鲁棒性强的特点。  相似文献   

17.
Designing a controller to stabilize maneuvering hovercrafts is an important challenge in amphibious vehicles.Hovercrafts are implemented in several applications,such as military missions,transportation,and scientific tasks.Thus.to improve their performance,it is crucial to control the system and compensate uncertainties and disruptions.In this paper,both classic and intelligent approaches are combined to design an observer-based controller.The system is assumed to be both controllable and observable.An adaptive neural network observer with guaranteed stability is derived for the nonlinear dynamics of a hovercraft,which is controlled via a nonsingular super-twisting terminal sliding-mode method.The main merits of the proposed method are as follows:(1) the Lyapunov stability of the overall closed-loop system,(2) the convergence of the tracking and observer errors to zero,(3) the robustness against uncertainties and disturbances,and(4) the reduction of the chattering phenomena.The simulation results validate the excellent performance of the derived method.  相似文献   

18.
Smith预报器在船舶航向控制上的应用   总被引:1,自引:0,他引:1  
在用PD控制船舶航向的基础上,加上Smith预报器,去除闭环特征方程中纯滞后因素的影响,达到改善系统的性能和控制器输出性能的目的。通过对船舶航向控制系统仿真的结果分析可知,如果系统的纯滞后不大,加上Smith预报器后,控制效果基本相同,而增加系统的纯滞后到一定程度时,具有Smith预报器的PD控制明显提高了系统的控制性能。  相似文献   

19.
This article presents a new approach for the prediction of motion sickness on ships, with a focus on high-speed craft. The methodology presented is based on a variant of the sensory conflict hypothesis and the human vestibular system. The proposed model was developed using control theory and is capable of taking account of all six degrees of freedom vessel motion for the prediction of motion sickness. Furthermore, full-scale trials were carried out onboard three different high-speed craft to measure the ship motions and consequently to analyse their effects on passengers in terms of motion sickness. Through the accumulated results, the developed model was validated and was compared with existing methods/criteria for the prediction of the incidence of motion sickness.  相似文献   

20.
In considering the characteristic of a rudder,the maneuvers of a ship were described by an unmatched uncertain nonlinear mathematic model with unknown virtual control coefficient and parameter uncertainties.In order to solve the uncertainties in the ship heading control,specifically the controller singular and paramount re-estimation problem,a new multiple sliding-mode adaptive fuzzy control algorithm was proposed by combining Nussbaum gain technology,the approximation property of fuzzy logic systems,and a multiple sliding-mode control algorithm.Based on the Lyapunov function,it was proven in theory that the controller made all signals in the nonlinear system of unmatched uncertain ship motion uniformly bounded,with tracking errors converging to zero.Simulation results show that the demonstrated controller design can track a desired course fast and accurately.It also exhibits strong robustness peculiarity in relation to system uncertainties and disturbances.  相似文献   

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