An improved hybrid position/force controller design of a flexible robot manipulator is presented using a sliding observer. The friction between the end effector and the environment is considered and compensated. For s...An improved hybrid position/force controller design of a flexible robot manipulator is presented using a sliding observer. The friction between the end effector and the environment is considered and compensated. For systematic reasons the controller is designed taking into consideration the rigid link subsystems and the flexible joints. The proposed control system satisfies the stability of the two subsystems and copes with the uncertainty of robot dynamics. A sliding observer is designed to estimate the time derivative of the torque applied as input to the rigid part of the robot. For the stability of the observer, it is assumed that the uncertainty of the observed system is bounded. A MRAC algorithm is used for the estimation of the friction forces at the contact point between the end effector and the environment. Finally simulation and experimental results are given, to demonstrate the effectiveness of the proposed controller.展开更多
As friction, intrinsic steady-state nonlinearity poses a challenging dilemma to the control system of 3-DOF （three degree of freedom） flight simulator, a novel hybrid control strategy of nonlinear PID （proportional...As friction, intrinsic steady-state nonlinearity poses a challenging dilemma to the control system of 3-DOF （three degree of freedom） flight simulator, a novel hybrid control strategy of nonlinear PID （proportionalintegral-derivative） with additional FFC （feed-forward controller） is proposed, and the hardware-in-the-loop simulation results are also given. Based on the description of 3-DOF flight simulator, a novel nonlinear PID theory is well introduced. Then a nonlinear PID controller with additional FFC is designed. Subsequently, the loop structure of 3-DOF flight simulator is also designed. Finally, a series of hardware-in-the-loop simulation experiments are undertaken to verify the feasibility and effectiveness of the proposed nonlinear PID controller with additional FFC for 3-DOF flight simulator.展开更多
Integration of water, fertilizer and pesticide is the final stage of agricultural development, which improves the utilization efficiency of water, fertilizer and pesticide. Starting from the design and realization of ...Integration of water, fertilizer and pesticide is the final stage of agricultural development, which improves the utilization efficiency of water, fertilizer and pesticide. Starting from the design and realization of water, fertilizer and pesticide integrated automatic control device, the paper discusses selection and application of fertilizer pesticides, use procedure, water, fertilizer and pesticide saving effect and receptive crowd in the application process of modern planting industry, so as to provide the basis for promotion and popularization of water, fertilizer and pesticide integration.展开更多
The structure and modeling of a novel unmanned coaxial rotor ducted fan helicopter(RDFH)are introduced,and then,based on the helicopter air dynamics and kinematics principles,a nonlinear model of the coaxial rotor duc...The structure and modeling of a novel unmanned coaxial rotor ducted fan helicopter(RDFH)are introduced,and then,based on the helicopter air dynamics and kinematics principles,a nonlinear model of the coaxial rotor ducted fan helicopter is developed and implemented on the basis of the wind tunnel experiment.After that,the helicopter′s stability and coupling characteristics of manipulation are analyzed through time-domain.Finally,a sliding mode controller(SMC)with boundary layers is developed on a hardware in the loop platform using digital signal processor(DSP)as the flight control computer.The results show that the RDFH′s tracking ability performs well under the use of proposed controller.展开更多
Se is one of trace elements necessary for the human body,and human body could absorb Se via the food. Se intake is insufficient in 2/3 region of China,which seriously affects health of local residents. Therefore,the r...Se is one of trace elements necessary for the human body,and human body could absorb Se via the food. Se intake is insufficient in 2/3 region of China,which seriously affects health of local residents. Therefore,the research of Se-rich fertilizer and the development of Se-rich product become the research focus in food science,medicine and other fields. There are rich marine resources in Beibu Gulf waters of Guangxi,and much carapace organic waste is generated. These carapace waste not only has high Se content but also is composed of a lot of Ca. The preparation of Se-rich ＆ high-Ca fertilizer by these carapace waste not only reaches the target of recycling and environment friendly but also increases the yield of agricultural products,reduces diseases and pests,improves quality,increases the added value of agricultural product,which brings better economic benefit and meets people＇s demand for healthy food.展开更多
文摘An improved hybrid position/force controller design of a flexible robot manipulator is presented using a sliding observer. The friction between the end effector and the environment is considered and compensated. For systematic reasons the controller is designed taking into consideration the rigid link subsystems and the flexible joints. The proposed control system satisfies the stability of the two subsystems and copes with the uncertainty of robot dynamics. A sliding observer is designed to estimate the time derivative of the torque applied as input to the rigid part of the robot. For the stability of the observer, it is assumed that the uncertainty of the observed system is bounded. A MRAC algorithm is used for the estimation of the friction forces at the contact point between the end effector and the environment. Finally simulation and experimental results are given, to demonstrate the effectiveness of the proposed controller.
基金the National Natural Science Foundation of China (60604009)Aeronautical Science Foundationof China(2006ZC51039)Beijing NOVA Program (2007A017).
文摘As friction, intrinsic steady-state nonlinearity poses a challenging dilemma to the control system of 3-DOF （three degree of freedom） flight simulator, a novel hybrid control strategy of nonlinear PID （proportionalintegral-derivative） with additional FFC （feed-forward controller） is proposed, and the hardware-in-the-loop simulation results are also given. Based on the description of 3-DOF flight simulator, a novel nonlinear PID theory is well introduced. Then a nonlinear PID controller with additional FFC is designed. Subsequently, the loop structure of 3-DOF flight simulator is also designed. Finally, a series of hardware-in-the-loop simulation experiments are undertaken to verify the feasibility and effectiveness of the proposed nonlinear PID controller with additional FFC for 3-DOF flight simulator.
基金Supported by Science and Technology Program of Guangxi Province(GK AD19245169,GK AD18281072,GK AA17202037,GK AB16380164)。
文摘Integration of water, fertilizer and pesticide is the final stage of agricultural development, which improves the utilization efficiency of water, fertilizer and pesticide. Starting from the design and realization of water, fertilizer and pesticide integrated automatic control device, the paper discusses selection and application of fertilizer pesticides, use procedure, water, fertilizer and pesticide saving effect and receptive crowd in the application process of modern planting industry, so as to provide the basis for promotion and popularization of water, fertilizer and pesticide integration.
基金supported by the National Natural Science Foundation of China(Nos.6130422361374116+1 种基金61503185)Specialized Research Fund for the Doctoral Program of Higher Education(20123218120015)
文摘The structure and modeling of a novel unmanned coaxial rotor ducted fan helicopter(RDFH)are introduced,and then,based on the helicopter air dynamics and kinematics principles,a nonlinear model of the coaxial rotor ducted fan helicopter is developed and implemented on the basis of the wind tunnel experiment.After that,the helicopter′s stability and coupling characteristics of manipulation are analyzed through time-domain.Finally,a sliding mode controller(SMC)with boundary layers is developed on a hardware in the loop platform using digital signal processor(DSP)as the flight control computer.The results show that the RDFH′s tracking ability performs well under the use of proposed controller.
基金Supported by Guangxi Science and Technology Plan Item(Guangxi Science AA17202037,Guangxi Science AB16380164,2015GXNSFAA139101)Xixiangtang Science and Technology Item of Nanning City(201710304)
文摘Se is one of trace elements necessary for the human body,and human body could absorb Se via the food. Se intake is insufficient in 2/3 region of China,which seriously affects health of local residents. Therefore,the research of Se-rich fertilizer and the development of Se-rich product become the research focus in food science,medicine and other fields. There are rich marine resources in Beibu Gulf waters of Guangxi,and much carapace organic waste is generated. These carapace waste not only has high Se content but also is composed of a lot of Ca. The preparation of Se-rich ＆ high-Ca fertilizer by these carapace waste not only reaches the target of recycling and environment friendly but also increases the yield of agricultural products,reduces diseases and pests,improves quality,increases the added value of agricultural product,which brings better economic benefit and meets people＇s demand for healthy food.
