A tracking stability control problem for the vertical electric stabilization system of moving tank based on adaptive robust servo control is addressed.This paper mainly focuses on two types of possibly fast timevaryin...A tracking stability control problem for the vertical electric stabilization system of moving tank based on adaptive robust servo control is addressed.This paper mainly focuses on two types of possibly fast timevarying but bounded uncertainty within the vertical electric stabilization system:model parameter uncertainty and uncertain nonlinearity.First,the vertical electric stabilization system is constructed as an uncertain nonlinear dynamic system that can reflect the practical mechanics transfer process of the system.Second,the dynamical equation in the form of state space is established by designing the angular tracking error.Third,the comprehensive parameter of system uncertainty is designed to estimate the most conservative effects of uncertainty.Finally,an adaptive robust servo control which can effectively handle the combined effects of complex nonlinearity and uncertainty is proposed.The feasibility of the proposed control strategy under the practical physical condition is validated through the tests on the experimental platform.This paper pioneers the introduction of the internal nonlinearity and uncertainty of the vertical electric stabilization system into the settlement of the tracking stability control problem,and validates the advanced servo control strategy through experiment for the first time.展开更多
A proportional integral derivative (PID) controller is designed and attached to electro-hydraulic servo actuator system (EHSAS) to control the angular position of the rotary actuator which control the movable surf...A proportional integral derivative (PID) controller is designed and attached to electro-hydraulic servo actuator system (EHSAS) to control the angular position of the rotary actuator which control the movable surface of space vehicles. The PID gain parameters are optimized by the genetic algorithm (GA). The controller is verified on the new state-space model of servo-valves attached to the physical rotary actuator by SIMULINK program. The controller and the state-space model are verified experimentally. Simulation and experimental results verify the effectiveness of the PID controller adaptive by GA to control the angular position of the rotary actuator as compared with the classical PID controller and the compensator controller.展开更多
Partial pressure, system vibration and asymmetric system dynamic performance exit in asymmetric cylinder controller by symmetric valve hydraulic system. To solve this problem in the force control system, model referen...Partial pressure, system vibration and asymmetric system dynamic performance exit in asymmetric cylinder controller by symmetric valve hydraulic system. To solve this problem in the force control system, model reference adaptive controller is designed using equilibrium point stability theory and output error equation polynomial. The reference model is selected in such a way that it meets the system dynamic performance. Hardware configuration of asymmetric cylinder controlled by asymmetric valve hydraulic system is replaced by intelligent control algorithm, thus the cost is lowered and easy to application. Simulation results demonstrate that the proposed adaptive control sheme has good adaptive ability and well solves asymmetric dynamic performance problem. The designed adaptive controller is fairly robust to load disturbance and system parameter variation.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
Combining the characteristics of servo systems , tracking variable structure control law is studied. Two kinds of new variable control law , the generalized exponential approaching vari- able structure control law and...Combining the characteristics of servo systems , tracking variable structure control law is studied. Two kinds of new variable control law , the generalized exponential approaching vari- able structure control law and the integral variable structure control law are put forward for dis- crete time domain. Taking pump-controlled-motor rotational speed servo system for example , the experiment investigation and digital simulation of integral variable structure control law for dis- crete time domain are performed , the rightness of conclusions are verified.展开更多
When adaptive robust control(ARC) strategy based on backstepping design is applied in pneumatic servo control, accurate pressure tracking in motion is especially necessary for both force and position trajectories tr...When adaptive robust control(ARC) strategy based on backstepping design is applied in pneumatic servo control, accurate pressure tracking in motion is especially necessary for both force and position trajectories tracking ofrodless pneumatic cylinders, and therefore an adaptive robust pressure controller is developed in this paper to improve the tracking accuracy of pressure trajectory in the chamber when the pneumatic cylinder is moving. In the proposed adaptive robust pressure controller, off-line fitting of the orifice area and on-line parameter estimation of the flow coefficient are utilized to have improved model compensation, and meanwhile robust feedback and Kalman filter are used to have strong robustness against uncertain nonlinearities, parameter fluctuations and noise. Research results demonstrate that the adaptive robust pressure controller could not only track various pressure trajectories accurately even when the pneumatic cylinder is moving, but also obtain very smooth control input, which indicates the effectiveness of adaptive model compensation. Especially when a step pressure trajectory is tracked under the condition of the movement of a rodless pneumatic cylinder, maximum tracking error of ARC is 4.46 kPa and average tracking error is 0.99 kPa, and steady-state error of ARC could achieve 0.84 kPa, which is very close to the measurement accuracy of pressure transducer.展开更多
To control the position of differential cylinder closed loop without usingany throttle elements, a flew idea that two speed variable pumps are used to compensate thenon-symmetric flow of differential cylinder is carri...To control the position of differential cylinder closed loop without usingany throttle elements, a flew idea that two speed variable pumps are used to compensate thenon-symmetric flow of differential cylinder is carried out. According to the leaking property of thesystem, a speed offset principle is also proposed to eliminate the cavitation and tension caused bythe leakage and condensation of oil, which makes the system be in the same state as a valvecontrolled circuit. This principle is explained theoretically and experimentally. Further therelationship that the pressures in cylinder chambers change with load and leakage, and therelationship between biasing speed and pre-load pressures in cylinder chambers are established. Theresearch has proved that the new system has similar technique features as those of controlled withservo valves, but due to the elimination of all the throttle lose the efficiency of system can beimproved greatly.展开更多
Voice coil motor(VCM) is a special direct drive linear motor, which can convert electric energy directly into mechanical energy without the use of transmission mechanism. VCM has the advantages of simple structure, go...Voice coil motor(VCM) is a special direct drive linear motor, which can convert electric energy directly into mechanical energy without the use of transmission mechanism. VCM has the advantages of simple structure, good rigidity, fast response, silence, high linearity, no cogging force, no pulsation et al. It is widely used in the field of high-precision control. This paper reviews and summarizes the results of VCM research conducted by scholars from various countries, and summarizes the general situation of VCM servo control technology. Firstly, a basic description of VCM’s mathematical model and common control mechanisms is provided. The benefits, drawbacks, and application of control techniques in the field of VCM are all explored in detail;At the same time, the methods to improve control strategy are proposed;Then, combined with the analysis and research of scholars in various countries on VCM, the problems of difficult to establish accurate model, friction disturbance and mechanical vibration of VCM and the solutions to the corresponding problems are summarized;Finally, a summary of VCM’s application fields is provided.展开更多
In IBVS (image based visual servoing), the error signal in image space should be transformed into the control signal in the input space quickly. To avoid the iterative adjustment and complicated inverse solution of im...In IBVS (image based visual servoing), the error signal in image space should be transformed into the control signal in the input space quickly. To avoid the iterative adjustment and complicated inverse solution of image Jacobian, CMAC (cerebellar model articulation controller) neural network is inserted into visual servo control loop to implement the nonlinear mapping. Two control schemes are used. Simulation results on two schemes are provided, which show a better tracking precision and stability can be achieved using scheme 2.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
A novel non-smooth controller of the second order double integrator system with a bounded disturbance is proposed,which stability is proved and which disturbance rejection capability is analyzed by MATLAB simulation e...A novel non-smooth controller of the second order double integrator system with a bounded disturbance is proposed,which stability is proved and which disturbance rejection capability is analyzed by MATLAB simulation experiments. The novel non-smooth output feedback controller and tracking differentiator are applied to control the azimuth servo systemof the small floating satellite antenna. The MATLAB simulation and hardware in the loop simulation experiments are conducted. The experiment results validate that the non-smooth output feedback controller with stronger surge and sudden disturbance rejection capability can realize the stable azimuth servo control of the small floating antenna to ensure the communication between the target satellite and the antenna with high quality.展开更多
A novel electro-hydraulic servo control algorithm was introduced. The primary idea of this algorithm was to combine the notion of model prediction with the generic model control (GMC). The performance of the GMC al-...A novel electro-hydraulic servo control algorithm was introduced. The primary idea of this algorithm was to combine the notion of model prediction with the generic model control (GMC). The performance of the GMC al- gorithm was improved by receding optimization and feedback correction. By the predictive model of output errors of an electro-hydraulic servo control system based on the improved weighted least square support vector machines (WLS-SVM) to forecast and compensate the future sequence errors, the control precision and robustness were im- proved. The improved GMC based on the improved WLS-SVM was applied to an electro-hydraulic servo control sys- tem for hot strip rolling control systems. The simulation results showed the feasibility and effectiveness of the pres- ent algorithm.展开更多
Passive torque servo system (PTSS) simulates aerodynamic load and exerts the load on actuation system, but PTSS endures position coupling disturbance from active motion of actuation system, and this inherent disturb...Passive torque servo system (PTSS) simulates aerodynamic load and exerts the load on actuation system, but PTSS endures position coupling disturbance from active motion of actuation system, and this inherent disturbance is called extra torque. The most important issue for PTSS controller design is how to eliminate the influence of extra torque. Using backstepping technique, adaptive fuzzy torque control (AFTC) algorithm is proposed for PTSS in this paper, which reflects the essential characteristics of PTSS and guarantees transient tracking performance as well as final tracking accuracy. Takagi-Sugeno (T-S) fuzzy logic system is utilized to compensate parametric uncertainties and unstructured uncertainties. The output velocity of actuator identified model is introduced into AFTC aiming to eliminate extra torque. The closed-loop stability is studied using small gain theorem and the control system is proved to be semiglobally uniformly ultimately bounded. The proposed AFTC algorithm is applied to an electric load simulator (ELS), and the comparative experimental results indicate that AFTC controller is effective for PTSS.展开更多
随着传感器技术(Transducer)、人机交互界面技术(HMI)技术、伺服高精度脉冲电机(Servo motor)的不断产生与创新,Servo Control Systems在整合集成上面临新的突破,集成这些技术可使跟随速度与精度大幅提升,进而反哺高精度制造业,为高精...随着传感器技术(Transducer)、人机交互界面技术(HMI)技术、伺服高精度脉冲电机(Servo motor)的不断产生与创新,Servo Control Systems在整合集成上面临新的突破,集成这些技术可使跟随速度与精度大幅提升,进而反哺高精度制造业,为高精度制造业带来效益。据此整合了一套"集成伺服随动控制系统"。文章从系统的基本线路结构、控制原理流程以及最终的软硬件组合实现进行了详细的描述。展开更多
The existing plastic forming equipment are mostly driven by traditional AC motors with long trans- mission chains, low efficiency, large size, low precision and poor dynamic response are the common disadvantages. In o...The existing plastic forming equipment are mostly driven by traditional AC motors with long trans- mission chains, low efficiency, large size, low precision and poor dynamic response are the common disadvantages. In order to realize high performance forming processes, the driving device should be improved, especially for com- plicated processing motions. Based on electric servo direct drive technology, a novel AC servo rotating and linear composite driving device is proposed, which features implementing both spindle rotation and feed motion with- out transmission, so that compact structure and precise control can be achieved. Flux switching topology is employed in the rotating drive component for strong robustness, and fractional slot is employed in the linear direct drive component for large force capability. Then the mechanical structure for compositing rotation and linear motion is designed. A device prototype is manufactured, machining of each component and the whole assembly are presented respectively. Commercial servo amplifiers are utilized to construct the control system of the proposed device. To validate the effectiveness of the proposed composite driving device, experimental study on thedynamic test benches are conducted. The results indicate that the output torque can attain to 420 N-m and the dynamic tracking errors are less than about 0.3 rad in the rotating drive, the dynamic tracking errors are less than about 1.6 mm in the linear feed. The proposed research provides a method to construct high efficiency and accu- racy direct driving device in plastic forming equipment.展开更多
Motion control can be considered as the synergistic collaboration of mechanical and electrical engineering, computer science and information technology to apply a controlled force to achieve useful motion in fluid or ...Motion control can be considered as the synergistic collaboration of mechanical and electrical engineering, computer science and information technology to apply a controlled force to achieve useful motion in fluid or soiled electromechanical systems. With the development of computer, electronics, and automatic control theory, motion control comes to a new stage. Great applications are based on the characteristics, stemming from advantages of electronics and modern control technology achievements, having a very good load matching property. Currently, microprocessor-based controllers are invariably used in most applications of drive electronics. The object of this work is to design a position control mechanism system, which can be used in test section of low speed wind tunnel. System load specifications and performance requirements are given. A comprehensive study of mathematical modeling of the mechanism components is given. Procedure for selection of various components with optimum parameters is discussed. After selection and calculation of system parameters to meet the performance requirements, a PID control method is adopted.展开更多
In order to further improve the tracking performances of the conventional disturbance observer(DOB)-based control schemes,a dual-loop robust control scheme is proposed for DC electro-mechanical servo system.The outer-...In order to further improve the tracking performances of the conventional disturbance observer(DOB)-based control schemes,a dual-loop robust control scheme is proposed for DC electro-mechanical servo system.The outer-loop sliding mode controller(SMC)is designed in order to deal with the impacts from the remainder equivalent disturbances,which is due to the inadequate estimation of the inner-loop DOB.Meanwhile,the existence of DOB can reduce the switching gain of SMC law,which can suppress the high-frequency chattering of control input to a certain extent.Moreover,an approximate differential method is employed in order to reliably acquire the differential information in a noisy environment.From the experiment results on a DC motor servo system,it is presented that the proposed dual-loop control scheme can effectively improve the tracking performances with respect to higher tracking accuracy and stronger system robustness against external disturbances and parameter perturbations,compared with the traditional DOB+PD control scheme.展开更多
The 30 kW high-power electric servo system used in the solid booster of the Long March 6 A(LM-6 A)launch vehicle is introduced,and the function,composition of the system as well as its constituent equipments are detai...The 30 kW high-power electric servo system used in the solid booster of the Long March 6 A(LM-6 A)launch vehicle is introduced,and the function,composition of the system as well as its constituent equipments are detailed.To solve the problem of out-of-tolerance in the system dynamic characteristics,an advanced correction network algorithm architecture and double notch filter were designed.Experimental verification was conducted to prove that the dynamic characteristics requirement under multiple operating conditions could be met.展开更多
The aircraft antiskid braking system is an important hydraulic system for preventing tire bursts and ensuring safe take-off and landing. The brake system adjusts the force applied on the brake discs by controlling the...The aircraft antiskid braking system is an important hydraulic system for preventing tire bursts and ensuring safe take-off and landing. The brake system adjusts the force applied on the brake discs by controlling the brake pressure. Traditional aircraft antiskid braking systems achieve antiskid performance by controlling the braking pressure with an electrohydraulic servo valve.Because the pilot stage of an electrohydraulic servo valve is easily blocked by carbonized hydraulic oil, the servo valve would become a dangerous weak point for aircraft safety. This paper proposes a new approach that uses an on-off valve array to replace the servo valve for pressure control. Based on this new pressure control component, an efficient antiskid control algorithm that can utilize this discontinuous feature is proposed. Furthermore, the algorithm has the ability to identify the runway circumstances. To overcome the discontinuity in the process of using an on-off valve array, the Filippov framework is introduced. The conditions of convergence of the system are also discussed.The results of the digital simulations and the hardware-in-the-loop(HIL) braking experiments are used to verify the efficiency and stability of the proposed control algorithm. The method also proves that the on-off valve array can replace the servo valve perfectly as a new type of antiskid braking pressure control component.展开更多
The recoil distance Doppler shift method has been widely used in the study of nuclear structure to determine the level lifetime and absolute transition probabilities.A capacitance servo control plunger based on this m...The recoil distance Doppler shift method has been widely used in the study of nuclear structure to determine the level lifetime and absolute transition probabilities.A capacitance servo control plunger based on this method has been successfully developed by the Nuclear Structure Group of the China Institute of Atomic Energy.Three microscopes were employed to check the parallelism and can therefore guarantee a delicate measurement of the distance between the target and the stopper.This new plunger made a successful performance in the test experiment and the measured lifetime of the 2~+→0~+ transition in ^(78)Kr is in agreement with the previous value.展开更多
基金supported in part by the Nation Natural Science Foundation of China under Grant No.52175099China Postdoctoral Science Foundation under Grant No.2020M671494Jiangsu Planned Projects for Postdoctoral Research Funds under Grant No.2020Z179。
文摘A tracking stability control problem for the vertical electric stabilization system of moving tank based on adaptive robust servo control is addressed.This paper mainly focuses on two types of possibly fast timevarying but bounded uncertainty within the vertical electric stabilization system:model parameter uncertainty and uncertain nonlinearity.First,the vertical electric stabilization system is constructed as an uncertain nonlinear dynamic system that can reflect the practical mechanics transfer process of the system.Second,the dynamical equation in the form of state space is established by designing the angular tracking error.Third,the comprehensive parameter of system uncertainty is designed to estimate the most conservative effects of uncertainty.Finally,an adaptive robust servo control which can effectively handle the combined effects of complex nonlinearity and uncertainty is proposed.The feasibility of the proposed control strategy under the practical physical condition is validated through the tests on the experimental platform.This paper pioneers the introduction of the internal nonlinearity and uncertainty of the vertical electric stabilization system into the settlement of the tracking stability control problem,and validates the advanced servo control strategy through experiment for the first time.
文摘A proportional integral derivative (PID) controller is designed and attached to electro-hydraulic servo actuator system (EHSAS) to control the angular position of the rotary actuator which control the movable surface of space vehicles. The PID gain parameters are optimized by the genetic algorithm (GA). The controller is verified on the new state-space model of servo-valves attached to the physical rotary actuator by SIMULINK program. The controller and the state-space model are verified experimentally. Simulation and experimental results verify the effectiveness of the PID controller adaptive by GA to control the angular position of the rotary actuator as compared with the classical PID controller and the compensator controller.
文摘Partial pressure, system vibration and asymmetric system dynamic performance exit in asymmetric cylinder controller by symmetric valve hydraulic system. To solve this problem in the force control system, model reference adaptive controller is designed using equilibrium point stability theory and output error equation polynomial. The reference model is selected in such a way that it meets the system dynamic performance. Hardware configuration of asymmetric cylinder controlled by asymmetric valve hydraulic system is replaced by intelligent control algorithm, thus the cost is lowered and easy to application. Simulation results demonstrate that the proposed adaptive control sheme has good adaptive ability and well solves asymmetric dynamic performance problem. The designed adaptive controller is fairly robust to load disturbance and system parameter variation.
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.
文摘Combining the characteristics of servo systems , tracking variable structure control law is studied. Two kinds of new variable control law , the generalized exponential approaching vari- able structure control law and the integral variable structure control law are put forward for dis- crete time domain. Taking pump-controlled-motor rotational speed servo system for example , the experiment investigation and digital simulation of integral variable structure control law for dis- crete time domain are performed , the rightness of conclusions are verified.
基金supported by National Natural Science Foundation of China (Grant No. 50775200)
文摘When adaptive robust control(ARC) strategy based on backstepping design is applied in pneumatic servo control, accurate pressure tracking in motion is especially necessary for both force and position trajectories tracking ofrodless pneumatic cylinders, and therefore an adaptive robust pressure controller is developed in this paper to improve the tracking accuracy of pressure trajectory in the chamber when the pneumatic cylinder is moving. In the proposed adaptive robust pressure controller, off-line fitting of the orifice area and on-line parameter estimation of the flow coefficient are utilized to have improved model compensation, and meanwhile robust feedback and Kalman filter are used to have strong robustness against uncertain nonlinearities, parameter fluctuations and noise. Research results demonstrate that the adaptive robust pressure controller could not only track various pressure trajectories accurately even when the pneumatic cylinder is moving, but also obtain very smooth control input, which indicates the effectiveness of adaptive model compensation. Especially when a step pressure trajectory is tracked under the condition of the movement of a rodless pneumatic cylinder, maximum tracking error of ARC is 4.46 kPa and average tracking error is 0.99 kPa, and steady-state error of ARC could achieve 0.84 kPa, which is very close to the measurement accuracy of pressure transducer.
基金This project is supported by National Natural Science Foundation of China(No.50275102) National Foundation for Abroad Return People, China (No.2001345).
文摘To control the position of differential cylinder closed loop without usingany throttle elements, a flew idea that two speed variable pumps are used to compensate thenon-symmetric flow of differential cylinder is carried out. According to the leaking property of thesystem, a speed offset principle is also proposed to eliminate the cavitation and tension caused bythe leakage and condensation of oil, which makes the system be in the same state as a valvecontrolled circuit. This principle is explained theoretically and experimentally. Further therelationship that the pressures in cylinder chambers change with load and leakage, and therelationship between biasing speed and pre-load pressures in cylinder chambers are established. Theresearch has proved that the new system has similar technique features as those of controlled withservo valves, but due to the elimination of all the throttle lose the efficiency of system can beimproved greatly.
文摘Voice coil motor(VCM) is a special direct drive linear motor, which can convert electric energy directly into mechanical energy without the use of transmission mechanism. VCM has the advantages of simple structure, good rigidity, fast response, silence, high linearity, no cogging force, no pulsation et al. It is widely used in the field of high-precision control. This paper reviews and summarizes the results of VCM research conducted by scholars from various countries, and summarizes the general situation of VCM servo control technology. Firstly, a basic description of VCM’s mathematical model and common control mechanisms is provided. The benefits, drawbacks, and application of control techniques in the field of VCM are all explored in detail;At the same time, the methods to improve control strategy are proposed;Then, combined with the analysis and research of scholars in various countries on VCM, the problems of difficult to establish accurate model, friction disturbance and mechanical vibration of VCM and the solutions to the corresponding problems are summarized;Finally, a summary of VCM’s application fields is provided.
基金This project is supported by National Natural Science Foundation of China (No.59990470).
文摘In IBVS (image based visual servoing), the error signal in image space should be transformed into the control signal in the input space quickly. To avoid the iterative adjustment and complicated inverse solution of image Jacobian, CMAC (cerebellar model articulation controller) neural network is inserted into visual servo control loop to implement the nonlinear mapping. Two control schemes are used. Simulation results on two schemes are provided, which show a better tracking precision and stability can be achieved using scheme 2.
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.
基金Supported by Academic Innovation Project of Beijing(201106149)
文摘A novel non-smooth controller of the second order double integrator system with a bounded disturbance is proposed,which stability is proved and which disturbance rejection capability is analyzed by MATLAB simulation experiments. The novel non-smooth output feedback controller and tracking differentiator are applied to control the azimuth servo systemof the small floating satellite antenna. The MATLAB simulation and hardware in the loop simulation experiments are conducted. The experiment results validate that the non-smooth output feedback controller with stronger surge and sudden disturbance rejection capability can realize the stable azimuth servo control of the small floating antenna to ensure the communication between the target satellite and the antenna with high quality.
基金Item Sponsored by National Development and Reform Commission Tech-Industry Project Foundation of China(High-Tech1899)
文摘A novel electro-hydraulic servo control algorithm was introduced. The primary idea of this algorithm was to combine the notion of model prediction with the generic model control (GMC). The performance of the GMC al- gorithm was improved by receding optimization and feedback correction. By the predictive model of output errors of an electro-hydraulic servo control system based on the improved weighted least square support vector machines (WLS-SVM) to forecast and compensate the future sequence errors, the control precision and robustness were im- proved. The improved GMC based on the improved WLS-SVM was applied to an electro-hydraulic servo control sys- tem for hot strip rolling control systems. The simulation results showed the feasibility and effectiveness of the pres- ent algorithm.
基金National High-tech Research and Development Program of China (2009AA04Z412)"111" ProjectBUAA Fund of Graduate Education and Development
文摘Passive torque servo system (PTSS) simulates aerodynamic load and exerts the load on actuation system, but PTSS endures position coupling disturbance from active motion of actuation system, and this inherent disturbance is called extra torque. The most important issue for PTSS controller design is how to eliminate the influence of extra torque. Using backstepping technique, adaptive fuzzy torque control (AFTC) algorithm is proposed for PTSS in this paper, which reflects the essential characteristics of PTSS and guarantees transient tracking performance as well as final tracking accuracy. Takagi-Sugeno (T-S) fuzzy logic system is utilized to compensate parametric uncertainties and unstructured uncertainties. The output velocity of actuator identified model is introduced into AFTC aiming to eliminate extra torque. The closed-loop stability is studied using small gain theorem and the control system is proved to be semiglobally uniformly ultimately bounded. The proposed AFTC algorithm is applied to an electric load simulator (ELS), and the comparative experimental results indicate that AFTC controller is effective for PTSS.
文摘随着传感器技术(Transducer)、人机交互界面技术(HMI)技术、伺服高精度脉冲电机(Servo motor)的不断产生与创新,Servo Control Systems在整合集成上面临新的突破,集成这些技术可使跟随速度与精度大幅提升,进而反哺高精度制造业,为高精度制造业带来效益。据此整合了一套"集成伺服随动控制系统"。文章从系统的基本线路结构、控制原理流程以及最终的软硬件组合实现进行了详细的描述。
基金Supported by National Natural Science Foundation of China(Grant No.51335009)Major National Science and Technology Project of China(Grant No.2011ZX04001-011)
文摘The existing plastic forming equipment are mostly driven by traditional AC motors with long trans- mission chains, low efficiency, large size, low precision and poor dynamic response are the common disadvantages. In order to realize high performance forming processes, the driving device should be improved, especially for com- plicated processing motions. Based on electric servo direct drive technology, a novel AC servo rotating and linear composite driving device is proposed, which features implementing both spindle rotation and feed motion with- out transmission, so that compact structure and precise control can be achieved. Flux switching topology is employed in the rotating drive component for strong robustness, and fractional slot is employed in the linear direct drive component for large force capability. Then the mechanical structure for compositing rotation and linear motion is designed. A device prototype is manufactured, machining of each component and the whole assembly are presented respectively. Commercial servo amplifiers are utilized to construct the control system of the proposed device. To validate the effectiveness of the proposed composite driving device, experimental study on thedynamic test benches are conducted. The results indicate that the output torque can attain to 420 N-m and the dynamic tracking errors are less than about 0.3 rad in the rotating drive, the dynamic tracking errors are less than about 1.6 mm in the linear feed. The proposed research provides a method to construct high efficiency and accu- racy direct driving device in plastic forming equipment.
文摘Motion control can be considered as the synergistic collaboration of mechanical and electrical engineering, computer science and information technology to apply a controlled force to achieve useful motion in fluid or soiled electromechanical systems. With the development of computer, electronics, and automatic control theory, motion control comes to a new stage. Great applications are based on the characteristics, stemming from advantages of electronics and modern control technology achievements, having a very good load matching property. Currently, microprocessor-based controllers are invariably used in most applications of drive electronics. The object of this work is to design a position control mechanism system, which can be used in test section of low speed wind tunnel. System load specifications and performance requirements are given. A comprehensive study of mathematical modeling of the mechanism components is given. Procedure for selection of various components with optimum parameters is discussed. After selection and calculation of system parameters to meet the performance requirements, a PID control method is adopted.
基金This work was financially supported by the National 863 Plan of China(Grant No.2012AA112201).
文摘In order to further improve the tracking performances of the conventional disturbance observer(DOB)-based control schemes,a dual-loop robust control scheme is proposed for DC electro-mechanical servo system.The outer-loop sliding mode controller(SMC)is designed in order to deal with the impacts from the remainder equivalent disturbances,which is due to the inadequate estimation of the inner-loop DOB.Meanwhile,the existence of DOB can reduce the switching gain of SMC law,which can suppress the high-frequency chattering of control input to a certain extent.Moreover,an approximate differential method is employed in order to reliably acquire the differential information in a noisy environment.From the experiment results on a DC motor servo system,it is presented that the proposed dual-loop control scheme can effectively improve the tracking performances with respect to higher tracking accuracy and stronger system robustness against external disturbances and parameter perturbations,compared with the traditional DOB+PD control scheme.
文摘The 30 kW high-power electric servo system used in the solid booster of the Long March 6 A(LM-6 A)launch vehicle is introduced,and the function,composition of the system as well as its constituent equipments are detailed.To solve the problem of out-of-tolerance in the system dynamic characteristics,an advanced correction network algorithm architecture and double notch filter were designed.Experimental verification was conducted to prove that the dynamic characteristics requirement under multiple operating conditions could be met.
基金the Science and Technology on Aircraft Control Laboratorythe National Nature Science Foundation of China (Nos. 51775014 and 51890882)
文摘The aircraft antiskid braking system is an important hydraulic system for preventing tire bursts and ensuring safe take-off and landing. The brake system adjusts the force applied on the brake discs by controlling the brake pressure. Traditional aircraft antiskid braking systems achieve antiskid performance by controlling the braking pressure with an electrohydraulic servo valve.Because the pilot stage of an electrohydraulic servo valve is easily blocked by carbonized hydraulic oil, the servo valve would become a dangerous weak point for aircraft safety. This paper proposes a new approach that uses an on-off valve array to replace the servo valve for pressure control. Based on this new pressure control component, an efficient antiskid control algorithm that can utilize this discontinuous feature is proposed. Furthermore, the algorithm has the ability to identify the runway circumstances. To overcome the discontinuity in the process of using an on-off valve array, the Filippov framework is introduced. The conditions of convergence of the system are also discussed.The results of the digital simulations and the hardware-in-the-loop(HIL) braking experiments are used to verify the efficiency and stability of the proposed control algorithm. The method also proves that the on-off valve array can replace the servo valve perfectly as a new type of antiskid braking pressure control component.
基金Supported by National Natural Science Foundation of China(10675171,10927507,11075214,11175259)
文摘The recoil distance Doppler shift method has been widely used in the study of nuclear structure to determine the level lifetime and absolute transition probabilities.A capacitance servo control plunger based on this method has been successfully developed by the Nuclear Structure Group of the China Institute of Atomic Energy.Three microscopes were employed to check the parallelism and can therefore guarantee a delicate measurement of the distance between the target and the stopper.This new plunger made a successful performance in the test experiment and the measured lifetime of the 2~+→0~+ transition in ^(78)Kr is in agreement with the previous value.