A path following controller is developed for underactuated ships with only surge force and yaw moment available to follow a predefined path.The proposed controller is based on nonswitch analytic model predictive contr...A path following controller is developed for underactuated ships with only surge force and yaw moment available to follow a predefined path.The proposed controller is based on nonswitch analytic model predictive control.It is shown that the optimal control law for a nonlinear path following system with ill-defined relative degree is continuous and nonsingular.The problem of ill-defined relative degree is solved.The path-following ability of the nonlinear system is guaranteed.Numerical simulations are provided to demonstrate the effectiveness of the proposed control law.展开更多
This paper presents an adaptive path following control law to steer underactuated ships along a predefined path at a constant forward speed with uncertain parameters due to changes of added mass matrices.The proposed ...This paper presents an adaptive path following control law to steer underactuated ships along a predefined path at a constant forward speed with uncertain parameters due to changes of added mass matrices.The proposed controller is based on analytic model predictive control and model reference adaptive control.The SerretFrenet frame is used to describe the ship dynamics.The analytic model predictive control provides a systematic method rather than try-and-error method to get appropriate control parameters to guarantee the stability of the closed-loop system,and the well-defined relative degree is guaranteed by introducing output-redefinition.An identification algorithm based on model reference adaptive control is used to identify the uncertain parameters.Numerical simulations are provided to demonstrate the validity of the proposed control law.展开更多
An adaptive robust control algorithm for ship straight path control system in the presence of both modeling uncertainties and the bounded disturbances is proposed. Motivated by the backstepping approach, the algorithm...An adaptive robust control algorithm for ship straight path control system in the presence of both modeling uncertainties and the bounded disturbances is proposed. Motivated by the backstepping approach, the algorithm is developed by using the dissipation theory, such that the resulting dosed-loop system is both strictly dissipative and asymptotically adaptively stable for all admissible uncertainties. Also, it is able to steer an underactuated ship along a prescribed straight path with ultimate bounds under external disturbances induced by wave, wind and ocean current. When there are no disturbances, the straight path control can be implemented in a locally asymptotically stable manner. Simulation results on an ocean-going training ship ‘YULONG＇ are presented to validate the effectiveness of the algorithm.展开更多
针对现有算法求解大规模船舶路径规划问题性能不佳且对涡旋等海洋环境因素考虑较少等问题,提出了一种基于惩罚信息素蚁群优化算法(punishment pheromone ant colony optimization,PPACO)的船舶路径规划方法。首先,设计了长度、风险和航...针对现有算法求解大规模船舶路径规划问题性能不佳且对涡旋等海洋环境因素考虑较少等问题,提出了一种基于惩罚信息素蚁群优化算法(punishment pheromone ant colony optimization,PPACO)的船舶路径规划方法。首先,设计了长度、风险和航向3个评价函数;其次利用强化学习启发的蚁群优化算法来搜索最优路径,在传统引导信息素的基础上加入了惩罚信息素,可以防止蚂蚁的无效搜索;最后对改进算法进行仿真实验,在静态环境下的规划结果表明,在路径长度、风险值和航向累积角等指标方面,本文算法相比较传统蚁群算法(ant colony optimization,ACO)、跳点搜索算法(jump point search,JPS)和双向搜索的改进蚁群算法表现出更优越的性能,相对于3个对比算法的最好指标,路径长度减少6.1%,风险值降低5.6%,航向积累角减少78.6%,迭代次数减少53.3%,改进显著。特别是在引入了中尺度涡旋和水流运动因素的情况下,本文算法仍能规划出更优的船舶航行路径,有着积极的应用意义。展开更多
为减少船舶在排放控制区(Emission Control Area,ECA)内的大气污染物排放,确保其在ECA内合规运行,设计一种融合多源数据感知功能与动态路径预测功能的智能监控系统。该系统基于船舶航行信号采集系统(Navigation Signal System,NSS)和EC...为减少船舶在排放控制区(Emission Control Area,ECA)内的大气污染物排放,确保其在ECA内合规运行,设计一种融合多源数据感知功能与动态路径预测功能的智能监控系统。该系统基于船舶航行信号采集系统(Navigation Signal System,NSS)和ECA智能在线监控系统实现通过不同通导设备获取的船舶航行数据的异构融合,结合自适应边界逼近算法(Adaptive Boundary Approximation Algorithm,ABAA)快速计算船舶与ECA的交互信息,包括航向距离、最短距离和到达时间等。该系统通过4G/5G和北斗卫星导航系统等通信网络实现船岸信息交互,具有阈值预警优化功能,能提醒船员提前切换燃油种类。在船讯网上随机选取船舶进行系统测试,验证该系统的有效性和可靠性。测试结果表明,该系统在不同环境下的性能稳定,能为船员提供实时、准确的监控信息,帮助其提前采取措施,确保船舶在ECA内合规运行。展开更多
基金supported by the National Natural Science Foundation of China(No.50779033)the National High Technology Research and Development Program(863 Program)of China(No.2007AA11Z250)
文摘A path following controller is developed for underactuated ships with only surge force and yaw moment available to follow a predefined path.The proposed controller is based on nonswitch analytic model predictive control.It is shown that the optimal control law for a nonlinear path following system with ill-defined relative degree is continuous and nonsingular.The problem of ill-defined relative degree is solved.The path-following ability of the nonlinear system is guaranteed.Numerical simulations are provided to demonstrate the effectiveness of the proposed control law.
基金the National Natural Science Foundation of China (No. 50779033)the National High Technology Research and Development Program (863) of China (No. 2007AA11Z250)
文摘This paper presents an adaptive path following control law to steer underactuated ships along a predefined path at a constant forward speed with uncertain parameters due to changes of added mass matrices.The proposed controller is based on analytic model predictive control and model reference adaptive control.The SerretFrenet frame is used to describe the ship dynamics.The analytic model predictive control provides a systematic method rather than try-and-error method to get appropriate control parameters to guarantee the stability of the closed-loop system,and the well-defined relative degree is guaranteed by introducing output-redefinition.An identification algorithm based on model reference adaptive control is used to identify the uncertain parameters.Numerical simulations are provided to demonstrate the validity of the proposed control law.
文摘An adaptive robust control algorithm for ship straight path control system in the presence of both modeling uncertainties and the bounded disturbances is proposed. Motivated by the backstepping approach, the algorithm is developed by using the dissipation theory, such that the resulting dosed-loop system is both strictly dissipative and asymptotically adaptively stable for all admissible uncertainties. Also, it is able to steer an underactuated ship along a prescribed straight path with ultimate bounds under external disturbances induced by wave, wind and ocean current. When there are no disturbances, the straight path control can be implemented in a locally asymptotically stable manner. Simulation results on an ocean-going training ship ‘YULONG＇ are presented to validate the effectiveness of the algorithm.
文摘针对现有算法求解大规模船舶路径规划问题性能不佳且对涡旋等海洋环境因素考虑较少等问题,提出了一种基于惩罚信息素蚁群优化算法(punishment pheromone ant colony optimization,PPACO)的船舶路径规划方法。首先,设计了长度、风险和航向3个评价函数;其次利用强化学习启发的蚁群优化算法来搜索最优路径,在传统引导信息素的基础上加入了惩罚信息素,可以防止蚂蚁的无效搜索;最后对改进算法进行仿真实验,在静态环境下的规划结果表明,在路径长度、风险值和航向累积角等指标方面,本文算法相比较传统蚁群算法(ant colony optimization,ACO)、跳点搜索算法(jump point search,JPS)和双向搜索的改进蚁群算法表现出更优越的性能,相对于3个对比算法的最好指标,路径长度减少6.1%,风险值降低5.6%,航向积累角减少78.6%,迭代次数减少53.3%,改进显著。特别是在引入了中尺度涡旋和水流运动因素的情况下,本文算法仍能规划出更优的船舶航行路径,有着积极的应用意义。
文摘为减少船舶在排放控制区(Emission Control Area,ECA)内的大气污染物排放,确保其在ECA内合规运行,设计一种融合多源数据感知功能与动态路径预测功能的智能监控系统。该系统基于船舶航行信号采集系统(Navigation Signal System,NSS)和ECA智能在线监控系统实现通过不同通导设备获取的船舶航行数据的异构融合,结合自适应边界逼近算法(Adaptive Boundary Approximation Algorithm,ABAA)快速计算船舶与ECA的交互信息,包括航向距离、最短距离和到达时间等。该系统通过4G/5G和北斗卫星导航系统等通信网络实现船岸信息交互,具有阈值预警优化功能,能提醒船员提前切换燃油种类。在船讯网上随机选取船舶进行系统测试,验证该系统的有效性和可靠性。测试结果表明,该系统在不同环境下的性能稳定,能为船员提供实时、准确的监控信息,帮助其提前采取措施,确保船舶在ECA内合规运行。
