Positioning with high precision piezoelectric actuators is widely used.To overcome positioning inaccuracy caused by hysteresis and creep of actuators,a precise tracking method for piezoelectric actuators using active ...Positioning with high precision piezoelectric actuators is widely used.To overcome positioning inaccuracy caused by hysteresis and creep of actuators,a precise tracking method for piezoelectric actuators using active disturbance rejection control(ADRC) has been proposed in this paper.This method,in real-time,actively estimates and compensates parameter uncertainties,nonlinear factors such as hysteresis,and external disturbances in the tracking system.Precise tracking of the piezoelectric actuator can be achieved without any form of feedforward compensations.The experimental results demonstrate that the active disturbance rejection controller can reduce tracking errors by over90%comparing with those using the PID controller.Those features of the proposed control method are very suitable for applications in adaptive optics.展开更多
This paper describes an automated path generation method for industrial robots. Based on force control, a robotic subsystem has been developed for path automatic generation or path learning. Using a dummy tool and rou...This paper describes an automated path generation method for industrial robots. Based on force control, a robotic subsystem has been developed for path automatic generation or path learning. Using a dummy tool and roughly taught guiding points around a part contour, the robot moves in position and force controlled hybrid mode, following the order of the guiding points and with contact force direction and value predefined. During the motion, robot actual position is recorded by the robot controller. After the motion, the recorded position data is used to generate a robot path program automatically. Robot lead-through may be used in the guiding point teaching. Furthermore, a GUI (graphical user interface) is developed on the teach pedant to guide through the guiding point creation and teaching, path learning, program verification and execution. The development has been incorporated into a robotic machining product option. Combination of the robot path learning function and GUI enhances the interaction between the robot and operator and drastically increases the level of robotic ease-of-use.展开更多
In this paper,a sliding mode control with perturbation estimation(SMCPE) coupled with an inverse hysteresis compensator is proposed for the motion tracking control of a microposition system with piezoelectric actuatio...In this paper,a sliding mode control with perturbation estimation(SMCPE) coupled with an inverse hysteresis compensator is proposed for the motion tracking control of a microposition system with piezoelectric actuation.The inverse hysteresis compensator is employed to cancel the hysteresis nonlinearity,thus reducing the nonlinear system to a linear system with an inversion error.Then,a SMCPE controller is adopted to deal with all the unmodeled dynamics and disturbances,aiming at improving the dynamic performance and the robustness of system.An experiment of a piezoelectric actuator is presented to demonstrate the feasibility and effectiveness of the proposed control scheme.The result shows that for a fast-rate control input,the proposed method is capable of leading to a good performance of system behavior.展开更多
基金Supported by the National Natural Science Foundation of China(No.11373048)
文摘Positioning with high precision piezoelectric actuators is widely used.To overcome positioning inaccuracy caused by hysteresis and creep of actuators,a precise tracking method for piezoelectric actuators using active disturbance rejection control(ADRC) has been proposed in this paper.This method,in real-time,actively estimates and compensates parameter uncertainties,nonlinear factors such as hysteresis,and external disturbances in the tracking system.Precise tracking of the piezoelectric actuator can be achieved without any form of feedforward compensations.The experimental results demonstrate that the active disturbance rejection controller can reduce tracking errors by over90%comparing with those using the PID controller.Those features of the proposed control method are very suitable for applications in adaptive optics.
文摘This paper describes an automated path generation method for industrial robots. Based on force control, a robotic subsystem has been developed for path automatic generation or path learning. Using a dummy tool and roughly taught guiding points around a part contour, the robot moves in position and force controlled hybrid mode, following the order of the guiding points and with contact force direction and value predefined. During the motion, robot actual position is recorded by the robot controller. After the motion, the recorded position data is used to generate a robot path program automatically. Robot lead-through may be used in the guiding point teaching. Furthermore, a GUI (graphical user interface) is developed on the teach pedant to guide through the guiding point creation and teaching, path learning, program verification and execution. The development has been incorporated into a robotic machining product option. Combination of the robot path learning function and GUI enhances the interaction between the robot and operator and drastically increases the level of robotic ease-of-use.
基金supported by National Science Foundation of China under Grant No.61304097Foundation for Innovative Research Groups of the National Natural Science Foundation of China under Grant No.61321002Program for Changjiang Scholars and Innovative Research Team in University under Grant No.IRT1208
文摘In this paper,a sliding mode control with perturbation estimation(SMCPE) coupled with an inverse hysteresis compensator is proposed for the motion tracking control of a microposition system with piezoelectric actuation.The inverse hysteresis compensator is employed to cancel the hysteresis nonlinearity,thus reducing the nonlinear system to a linear system with an inversion error.Then,a SMCPE controller is adopted to deal with all the unmodeled dynamics and disturbances,aiming at improving the dynamic performance and the robustness of system.An experiment of a piezoelectric actuator is presented to demonstrate the feasibility and effectiveness of the proposed control scheme.The result shows that for a fast-rate control input,the proposed method is capable of leading to a good performance of system behavior.