Electro-hydraulic servo valve is a typical complicated multi-domain system constituted by mechanical, electric, hydraulic and magnetic components, which is widely used in electro-hydraulic servo systems such as constr...Electro-hydraulic servo valve is a typical complicated multi-domain system constituted by mechanical, electric, hydraulic and magnetic components, which is widely used in electro-hydraulic servo systems such as construction machinery, heavy equipment, weapon and so forth. The traditional method of modeling and simulation of servo valve is based on block diagram or signal flow, which cannot describe the servo valve system from components level nor be used in modeling and simulation of overall servo systems. In the procedure of traditional method, computational causality must be involved in modeling of servo valve, which is inconvenient to execute modification on components or parameters. Modelica is an object-oriented modeling language which is suited for large, complex, heterogeneous and multi-domain systems. The key features of Modelica are multi-domain, object-oriented and non-causal, which are suitable for modeling of servo valve and make the model readable, reusable, and easy to modify. The simulation results show similar curves with traditional method. This new servo valve modeling and simulation method can provide the engineers a more efficient way to design and optimize a servo valve and an overall servo system.展开更多
Adaptive control of servo actuator with nonlinear friction compensation is addressed. LuGre dynamic friction model is adopted to characterize the nonlinear friction and a new kind of slid ing mode observer is designe...Adaptive control of servo actuator with nonlinear friction compensation is addressed. LuGre dynamic friction model is adopted to characterize the nonlinear friction and a new kind of slid ing mode observer is designed to estimate the internal immeasurable state of LuGre model. Based on the estimated friction state, adaptive laws are designed to identify the unknown model parameters and the external disturbances, and the system stability and asymptotic trajectory tracking perform ance are guaranteed by Lyapunov function. The position tracking performance is verified by the ex perimental results.展开更多
Jet pipe electro-hydraulic servo valve is the heart of feedback control systems,and it is one of the mechatronic components used for precision flow control application.It consists of several precision and ddicate comp...Jet pipe electro-hydraulic servo valve is the heart of feedback control systems,and it is one of the mechatronic components used for precision flow control application.It consists of several precision and ddicate components.The performance of the jet pipe servo valve depends on many parameters.During the developmental stage,it is very difficult to ascertain the function parameters.The steady-state analysis of jet pipe electro-hydraulic servo valve has been made to simulate its fluid characteristics （flowin,flow-out,leakage flow,recovery or load pressure,etc.） by mathematical modeling.Theoretical model was conducted on various affecting parameters on the pressure,the main flow rate of fluid,or leakage flow through the receiver holes.The major parameters studied are jet pipe nozzle diameters,receiver hole diameters,angle between the two centre-lines of receiver hole,nozzle offset,and nozzle stand-of distance.In this paper the research is important to determine and optimize the structural parameters of jet pipe servo valve.Thus,equations of the pressure and flow characteristics are set up and the optimal structural parameters of jet pipe are established.展开更多
The angular position controller is system （EHSAS） to control the output of the rotary applied to electro-hydraulic servo actuator actuator. It works as a compensator based on the frequency response of the EHSAS. Its...The angular position controller is system （EHSAS） to control the output of the rotary applied to electro-hydraulic servo actuator actuator. It works as a compensator based on the frequency response of the EHSAS. Its design model is verified on the state-space model of EHSAS by using simulation program SIMULINK. Real data used to test the system. Simulation results give a good agreement for the controller and also for the state-space model.展开更多
The tele-operation robotic system which consists of an excavator as the construction robot, and two joysticks for operating the robot from a safe place are useful for performing restoration in damaged areas. In order ...The tele-operation robotic system which consists of an excavator as the construction robot, and two joysticks for operating the robot from a safe place are useful for performing restoration in damaged areas. In order to accomplish a precise task, the operator needs to feel a realistic sense of task force brought about from a feedback force between the fork glove of slave robot and unfamiliar environment. A novel force feedback model is proposed based on velocity control of cylinder to determine environment force acting on fork glove. Namely, the feedback force is formed by the error of displacement of joystick with velocity and driving force of piston, and the gain is calculated by the driving force and threshold of driving force of hydraulic cylinder. Moreover, the variable gain improved algorithm is developed to overcome the defect for grasping soft object. Experimental results for fork glove freedom of robotic system are provided to demonstrate the developed algorithm is available for grasping soft object.展开更多
针对在GPS信号弱/拒止和环境感知欠缺的环境下可重构海洋浮体的协同控制问题,本文提出了一种基于定相对位姿(Determined relative pose,DRP)视觉伺服模型的鲁棒非线性模型预测控制(Nonlinear model predictive control,NMPC)方案。可重...针对在GPS信号弱/拒止和环境感知欠缺的环境下可重构海洋浮体的协同控制问题,本文提出了一种基于定相对位姿(Determined relative pose,DRP)视觉伺服模型的鲁棒非线性模型预测控制(Nonlinear model predictive control,NMPC)方案。可重构海洋浮体的视觉伺服问题难点主要包括环境干扰强、系统非线性程度高、视觉伺服易陷入局部极值和可见性约束强。为应对这些难题,该视觉伺服控制策略需要实现:被控船仅依靠视觉信息进行多船协同控制;视觉伺服模型收敛性好;控制器具有一定鲁棒性且处理非线性系统和约束条件的能力强。为此,本研究首先建立了单浮体的动力学模型;然后将视觉模型、被控船艏摇信息及相机云台转角信息整合到系统状态中,形成了DRP模型,从而保证了双浮体视觉伺服控制结束后相对位姿的唯一性;接着结合浮体动力学模型和DRP模型,建立了基于图像的视觉伺服(Image based visual servo,IBVS)的系统模型,并对该系统模型进行分析,进而据此设计了鲁棒的NMPC控制器,以保证视觉伺服任务可以在强外界干扰的环境下进行;最后通过大量数值仿真实验验证了该方案的有效性。这些实验结果不仅证明了控制策略的稳定性和准确性,还展示了其在复杂环境下的鲁棒性能。展开更多
新一代战斗机和航空发动机研制对全机能量管理及发动机功率提取提出了更高的要求,迫切需要航空发动机伺服机构具备功率受限条件下正常工作的能力。针对功率受限条件下伺服机构控制目标多、约束多,传统PID控制难以满足预期的问题,提出一...新一代战斗机和航空发动机研制对全机能量管理及发动机功率提取提出了更高的要求,迫切需要航空发动机伺服机构具备功率受限条件下正常工作的能力。针对功率受限条件下伺服机构控制目标多、约束多,传统PID控制难以满足预期的问题,提出一种基于模型预测控制的最优控制方法,构建伺服机构的非线性模型,使用有限控制集(Finite Control Set,FCS)思想对输出进行解耦及线性化,综合多重目标要素设计损失函数和约束方程,从而得到了最优控制输出。仿真结果表明:在典型运行场景下,文章方法可使伺服系统实际峰值功率降低32.9%,而上升时间仅增加7.1%,实现了伺服机构的全局最优控制,为新一代飞机与航空发动机的集成研制提供了有益参考。展开更多
基金supported by the National High Technology Research and Development Foundation of China(2009AA044501)the National Basic Research Program of China (2011CB706502)
文摘Electro-hydraulic servo valve is a typical complicated multi-domain system constituted by mechanical, electric, hydraulic and magnetic components, which is widely used in electro-hydraulic servo systems such as construction machinery, heavy equipment, weapon and so forth. The traditional method of modeling and simulation of servo valve is based on block diagram or signal flow, which cannot describe the servo valve system from components level nor be used in modeling and simulation of overall servo systems. In the procedure of traditional method, computational causality must be involved in modeling of servo valve, which is inconvenient to execute modification on components or parameters. Modelica is an object-oriented modeling language which is suited for large, complex, heterogeneous and multi-domain systems. The key features of Modelica are multi-domain, object-oriented and non-causal, which are suitable for modeling of servo valve and make the model readable, reusable, and easy to modify. The simulation results show similar curves with traditional method. This new servo valve modeling and simulation method can provide the engineers a more efficient way to design and optimize a servo valve and an overall servo system.
基金Supported by State Key Laboratory of Explosion Science and Technology(QNKT11-08)
文摘Adaptive control of servo actuator with nonlinear friction compensation is addressed. LuGre dynamic friction model is adopted to characterize the nonlinear friction and a new kind of slid ing mode observer is designed to estimate the internal immeasurable state of LuGre model. Based on the estimated friction state, adaptive laws are designed to identify the unknown model parameters and the external disturbances, and the system stability and asymptotic trajectory tracking perform ance are guaranteed by Lyapunov function. The position tracking performance is verified by the ex perimental results.
基金National Science and Technology Supporting Program,China(No.2011BAJ02B06)Aeronautical Science Foundation of China(No.20090738003)National Natural Science Foundations of China(No.51175378,No.50775161)
文摘Jet pipe electro-hydraulic servo valve is the heart of feedback control systems,and it is one of the mechatronic components used for precision flow control application.It consists of several precision and ddicate components.The performance of the jet pipe servo valve depends on many parameters.During the developmental stage,it is very difficult to ascertain the function parameters.The steady-state analysis of jet pipe electro-hydraulic servo valve has been made to simulate its fluid characteristics （flowin,flow-out,leakage flow,recovery or load pressure,etc.） by mathematical modeling.Theoretical model was conducted on various affecting parameters on the pressure,the main flow rate of fluid,or leakage flow through the receiver holes.The major parameters studied are jet pipe nozzle diameters,receiver hole diameters,angle between the two centre-lines of receiver hole,nozzle offset,and nozzle stand-of distance.In this paper the research is important to determine and optimize the structural parameters of jet pipe servo valve.Thus,equations of the pressure and flow characteristics are set up and the optimal structural parameters of jet pipe are established.
文摘The angular position controller is system （EHSAS） to control the output of the rotary applied to electro-hydraulic servo actuator actuator. It works as a compensator based on the frequency response of the EHSAS. Its design model is verified on the state-space model of EHSAS by using simulation program SIMULINK. Real data used to test the system. Simulation results give a good agreement for the controller and also for the state-space model.
基金supported by National Natural Science Foundation of China(No.50475011).
文摘The tele-operation robotic system which consists of an excavator as the construction robot, and two joysticks for operating the robot from a safe place are useful for performing restoration in damaged areas. In order to accomplish a precise task, the operator needs to feel a realistic sense of task force brought about from a feedback force between the fork glove of slave robot and unfamiliar environment. A novel force feedback model is proposed based on velocity control of cylinder to determine environment force acting on fork glove. Namely, the feedback force is formed by the error of displacement of joystick with velocity and driving force of piston, and the gain is calculated by the driving force and threshold of driving force of hydraulic cylinder. Moreover, the variable gain improved algorithm is developed to overcome the defect for grasping soft object. Experimental results for fork glove freedom of robotic system are provided to demonstrate the developed algorithm is available for grasping soft object.
文摘针对在GPS信号弱/拒止和环境感知欠缺的环境下可重构海洋浮体的协同控制问题,本文提出了一种基于定相对位姿(Determined relative pose,DRP)视觉伺服模型的鲁棒非线性模型预测控制(Nonlinear model predictive control,NMPC)方案。可重构海洋浮体的视觉伺服问题难点主要包括环境干扰强、系统非线性程度高、视觉伺服易陷入局部极值和可见性约束强。为应对这些难题,该视觉伺服控制策略需要实现:被控船仅依靠视觉信息进行多船协同控制;视觉伺服模型收敛性好;控制器具有一定鲁棒性且处理非线性系统和约束条件的能力强。为此,本研究首先建立了单浮体的动力学模型;然后将视觉模型、被控船艏摇信息及相机云台转角信息整合到系统状态中,形成了DRP模型,从而保证了双浮体视觉伺服控制结束后相对位姿的唯一性;接着结合浮体动力学模型和DRP模型,建立了基于图像的视觉伺服(Image based visual servo,IBVS)的系统模型,并对该系统模型进行分析,进而据此设计了鲁棒的NMPC控制器,以保证视觉伺服任务可以在强外界干扰的环境下进行;最后通过大量数值仿真实验验证了该方案的有效性。这些实验结果不仅证明了控制策略的稳定性和准确性,还展示了其在复杂环境下的鲁棒性能。
文摘新一代战斗机和航空发动机研制对全机能量管理及发动机功率提取提出了更高的要求,迫切需要航空发动机伺服机构具备功率受限条件下正常工作的能力。针对功率受限条件下伺服机构控制目标多、约束多,传统PID控制难以满足预期的问题,提出一种基于模型预测控制的最优控制方法,构建伺服机构的非线性模型,使用有限控制集(Finite Control Set,FCS)思想对输出进行解耦及线性化,综合多重目标要素设计损失函数和约束方程,从而得到了最优控制输出。仿真结果表明:在典型运行场景下,文章方法可使伺服系统实际峰值功率降低32.9%,而上升时间仅增加7.1%,实现了伺服机构的全局最优控制,为新一代飞机与航空发动机的集成研制提供了有益参考。
