In this paper,a novel control structure called feedback scheduling of model-based networked control systems is proposed to cope with a flexible network load and resource constraints.The state update time is adjusted a...In this paper,a novel control structure called feedback scheduling of model-based networked control systems is proposed to cope with a flexible network load and resource constraints.The state update time is adjusted according to the real-time network congestion situation.State observer is used under the situation where the state of the controlled plant could not be acquired.The stability criterion of the proposed structure is proved with time-varying state update time.On the basis of the stability of the novel system structure,the compromise between the control performance and the network utilization is realized by using feedback scheduler. Examples are provided to show the advantage of the proposed control structure.展开更多
Various control systems for a robotic excavator named LUCIE (Lancaster University Computerized and Intelligent Excavator),were investigated. The excavator is being developed to dig trenches autonomously. One stumbling...Various control systems for a robotic excavator named LUCIE (Lancaster University Computerized and Intelligent Excavator),were investigated. The excavator is being developed to dig trenches autonomously. One stumbling block is the achievement of adequate,accurate,quick and smooth movement under automatic control. Here,both classical and modern approaches are considered,including proportional-integral-derivative (PID) control tuned by conventional Zigler-Nichols rules,linear proportional-integral-plus (PIP) control,and a novel nonlinear PIP controller based on a state-dependent parameter (SDP) model structure,in which the parameters are functionally dependent on other variables in the system. Implementation results for the excavator joint arms control demonstrate that SDP-PIP controller provides the improved performance with fast,smooth and accurate response in comparison with both PID and linearized PIP control.展开更多
研究了全桥型DC/DC变换器系统的控制方法。针对现有DC/DC变换器动态响应速度慢、抗干扰能力差的现状,提出了基于状态反馈精确线性化的动态矩阵控制-比例积分微分DMC-PID(dynamic matrix control-proportional integral differential)串...研究了全桥型DC/DC变换器系统的控制方法。针对现有DC/DC变换器动态响应速度慢、抗干扰能力差的现状,提出了基于状态反馈精确线性化的动态矩阵控制-比例积分微分DMC-PID(dynamic matrix control-proportional integral differential)串级控制方法。应用状态空间平均法建立全桥型DC/DC变换器系统的非线性模型,通过状态反馈精确线性化后得到线性化系统。为使系统获得优良的控制性能,选取DMC-PID串级控制方法。该控制方法同时具备PID算法的鲁棒性和DMC算法的快速性和稳定性,能有效地解决电源输入电压大范围波动输出电压不能及时稳定的问题。通过仿真分析和实验验证了该方案能在各种扰动工作条件下实现对变换器输出精确、快速的控制。展开更多
文摘In this paper,a novel control structure called feedback scheduling of model-based networked control systems is proposed to cope with a flexible network load and resource constraints.The state update time is adjusted according to the real-time network congestion situation.State observer is used under the situation where the state of the controlled plant could not be acquired.The stability criterion of the proposed structure is proved with time-varying state update time.On the basis of the stability of the novel system structure,the compromise between the control performance and the network utilization is realized by using feedback scheduler. Examples are provided to show the advantage of the proposed control structure.
基金Work supported by the Lancaster University,UK and Jiangsu Provincial Laboratory of Advanced Robotics,SooChow University,ChinaProject(BK2009509) supported by the Natural Science Foundation of Jiangsu Province,China+1 种基金Project(K5117827) supported by the Scientific Research Foundation for the Returned Scholars,Ministry of Education of ChinaProject(Q3117918) supported by the Scientific Research Foundation for Young Teachers of Soochow University,China
文摘Various control systems for a robotic excavator named LUCIE (Lancaster University Computerized and Intelligent Excavator),were investigated. The excavator is being developed to dig trenches autonomously. One stumbling block is the achievement of adequate,accurate,quick and smooth movement under automatic control. Here,both classical and modern approaches are considered,including proportional-integral-derivative (PID) control tuned by conventional Zigler-Nichols rules,linear proportional-integral-plus (PIP) control,and a novel nonlinear PIP controller based on a state-dependent parameter (SDP) model structure,in which the parameters are functionally dependent on other variables in the system. Implementation results for the excavator joint arms control demonstrate that SDP-PIP controller provides the improved performance with fast,smooth and accurate response in comparison with both PID and linearized PIP control.
文摘研究了全桥型DC/DC变换器系统的控制方法。针对现有DC/DC变换器动态响应速度慢、抗干扰能力差的现状,提出了基于状态反馈精确线性化的动态矩阵控制-比例积分微分DMC-PID(dynamic matrix control-proportional integral differential)串级控制方法。应用状态空间平均法建立全桥型DC/DC变换器系统的非线性模型,通过状态反馈精确线性化后得到线性化系统。为使系统获得优良的控制性能,选取DMC-PID串级控制方法。该控制方法同时具备PID算法的鲁棒性和DMC算法的快速性和稳定性,能有效地解决电源输入电压大范围波动输出电压不能及时稳定的问题。通过仿真分析和实验验证了该方案能在各种扰动工作条件下实现对变换器输出精确、快速的控制。
