CIFER software is used to identify steering and roll dynamics of a container ship. In this software, advanced features such as the Chirp-Z transform(CZT) and composite window optimization are applied to the time histo...CIFER software is used to identify steering and roll dynamics of a container ship. In this software, advanced features such as the Chirp-Z transform(CZT) and composite window optimization are applied to the time history of steering and roll dynamics to extract high quality frequency responses. From the extracted frequency responses, two linear transfer functions of Nomoto model are fitted for yaw and roll dynamics of the vessel. Based on the identified Nomoto model, a PID heading controller and a Kalman filter observer are constructed. The simulation results of heading controller for line of sight(LOS) waypoint guidance show excellent tracking of pilot inputs in the presence of wave induced motions and forces.展开更多
[目的]针对舵机故障、控制增益未知和海洋环境干扰情况下的欠驱动船舶航向保持问题,设计一种考虑舵机故障的船舶鲁棒自适应航向保持控制算法。[方法]通过结合鲁棒神经阻尼技术和自适应方法,对繁重的神经网络权值进行横向压缩,仅需设计2...[目的]针对舵机故障、控制增益未知和海洋环境干扰情况下的欠驱动船舶航向保持问题,设计一种考虑舵机故障的船舶鲁棒自适应航向保持控制算法。[方法]通过结合鲁棒神经阻尼技术和自适应方法,对繁重的神经网络权值进行横向压缩,仅需设计2个自适应学习参数对未知增益和舵机故障参数在线补偿,以确保船舶在舵机故障的情况下能够有效执行航向保持任务。通过李雅普诺夫理论,证明所提出的控制器半全局最终一致稳定有界(semi-global uniform and ultimately bounded,SGUUB)。最后以“育鲲”轮为仿真对象,建立非线性Nomoto数学模型,在海洋干扰下进行对比仿真试验验证。[结果]结果表明,在此策略下,“育鲲”轮在舵机故障情况下平均舵角输出比仿真试验中所对比的传统方法降低了51%,可改善航向保持控制效果。[结论]研究结果可为欠驱动船舶的航向保持控制问题提供借鉴。展开更多
针对受外界海洋环境扰动的欠驱动船舶航向保持控制问题,设计一种基于鲁棒自适应扰动观测器的船舶航向保持控制算法。通过Lyapunov理论,证明设计的控制器半全局一致最终有界稳定(Semi-Global Uniform and Ultimately Bounded,SGUUB)。以...针对受外界海洋环境扰动的欠驱动船舶航向保持控制问题,设计一种基于鲁棒自适应扰动观测器的船舶航向保持控制算法。通过Lyapunov理论,证明设计的控制器半全局一致最终有界稳定(Semi-Global Uniform and Ultimately Bounded,SGUUB)。以“育鲲”轮为船舶模型,建立考虑外界干扰的非线性Nomoto数学模型,在4级海况下进行航向保持仿真试验,并且与已有的控制算法进行对比,仿真结果表明:在达到稳定之后,基于鲁棒自适应扰动观测器的船舶航向保持器能使舵机操舵频率明显下降,舵机损耗较低,进一步验证提出的控制器算法具有较好的控制效果和鲁棒性。展开更多
The objective of this research was to determine the Nomoto model maneuverability indices of an agricultural unmanned airboat which was developed to perform autonomous weeding and paddy growth monitoring in a paddy fie...The objective of this research was to determine the Nomoto model maneuverability indices of an agricultural unmanned airboat which was developed to perform autonomous weeding and paddy growth monitoring in a paddy field.A global positioning system compass and an inertial measurement unit were attached on the airboat body to record the position,heading and angular rate.The zig-zag experiments were adopted to obtain the maneuverability indices.The Matlab-based maneuvering simulations were conducted and compared with field experimental data of circular motion test and sinusoidal running test,respectively.The results showed that the trace error was at sub-meter level,which expounds the validity of the obtained maneuvering indices.The proposed Nomoto model maneuverability indices can be used to improve the airboat precise automatic control in paddy field.展开更多
文摘CIFER software is used to identify steering and roll dynamics of a container ship. In this software, advanced features such as the Chirp-Z transform(CZT) and composite window optimization are applied to the time history of steering and roll dynamics to extract high quality frequency responses. From the extracted frequency responses, two linear transfer functions of Nomoto model are fitted for yaw and roll dynamics of the vessel. Based on the identified Nomoto model, a PID heading controller and a Kalman filter observer are constructed. The simulation results of heading controller for line of sight(LOS) waypoint guidance show excellent tracking of pilot inputs in the presence of wave induced motions and forces.
文摘[目的]针对舵机故障、控制增益未知和海洋环境干扰情况下的欠驱动船舶航向保持问题,设计一种考虑舵机故障的船舶鲁棒自适应航向保持控制算法。[方法]通过结合鲁棒神经阻尼技术和自适应方法,对繁重的神经网络权值进行横向压缩,仅需设计2个自适应学习参数对未知增益和舵机故障参数在线补偿,以确保船舶在舵机故障的情况下能够有效执行航向保持任务。通过李雅普诺夫理论,证明所提出的控制器半全局最终一致稳定有界(semi-global uniform and ultimately bounded,SGUUB)。最后以“育鲲”轮为仿真对象,建立非线性Nomoto数学模型,在海洋干扰下进行对比仿真试验验证。[结果]结果表明,在此策略下,“育鲲”轮在舵机故障情况下平均舵角输出比仿真试验中所对比的传统方法降低了51%,可改善航向保持控制效果。[结论]研究结果可为欠驱动船舶的航向保持控制问题提供借鉴。
文摘针对受外界海洋环境扰动的欠驱动船舶航向保持控制问题,设计一种基于鲁棒自适应扰动观测器的船舶航向保持控制算法。通过Lyapunov理论,证明设计的控制器半全局一致最终有界稳定(Semi-Global Uniform and Ultimately Bounded,SGUUB)。以“育鲲”轮为船舶模型,建立考虑外界干扰的非线性Nomoto数学模型,在4级海况下进行航向保持仿真试验,并且与已有的控制算法进行对比,仿真结果表明:在达到稳定之后,基于鲁棒自适应扰动观测器的船舶航向保持器能使舵机操舵频率明显下降,舵机损耗较低,进一步验证提出的控制器算法具有较好的控制效果和鲁棒性。
文摘The objective of this research was to determine the Nomoto model maneuverability indices of an agricultural unmanned airboat which was developed to perform autonomous weeding and paddy growth monitoring in a paddy field.A global positioning system compass and an inertial measurement unit were attached on the airboat body to record the position,heading and angular rate.The zig-zag experiments were adopted to obtain the maneuverability indices.The Matlab-based maneuvering simulations were conducted and compared with field experimental data of circular motion test and sinusoidal running test,respectively.The results showed that the trace error was at sub-meter level,which expounds the validity of the obtained maneuvering indices.The proposed Nomoto model maneuverability indices can be used to improve the airboat precise automatic control in paddy field.
