In this paper,some kinds of linear and nonlinear tracking-differentiators are designed by using suitable exponent functions instead of switch functions,and the stability of these tracking-differentiators is proved.Fro...In this paper,some kinds of linear and nonlinear tracking-differentiators are designed by using suitable exponent functions instead of switch functions,and the stability of these tracking-differentiators is proved.From the result of simulations,it is manifest that the tracking speeds of these kinds of linear and nonlinear tracking-differentiators are very high,and their design procedures are simple.展开更多
A filtering algorithm and direction identification method are presented for the positioning system of the mid-speed maglev train. Considering the special structure of the mid-speed maglev train, the ground position es...A filtering algorithm and direction identification method are presented for the positioning system of the mid-speed maglev train. Considering the special structure of the mid-speed maglev train, the ground position estimation method is adopted for its traction system. As the train is running, the induction loop-cable receives the signal sent by the on-board antenna to detect the position and direction of the train. But the height of the on-board antenna relative to the loop-cable is highly vulnerable to the change of the suspension height and the magnetic field produced by the traction during traveling, which may lead to amplitude fluctuation of the received signal. Consequently, the position estimation may be inaccurate. Therefore, a discrete second-order nonlinear trackdifferentiator is proposed based on the boundary characteristic curves, and the new differentiator could also extract the running direction of the train for the traction system. The experimental results show that the tracking differentiator can effectively filter out the signal interference and can provide accurate direction signal.展开更多
The total disturbance estimated by the extended state observer(ESO)in active disturbance rejection controller(ADRC)is affected greatly by measurement noise when the control step is small in heading control of underwat...The total disturbance estimated by the extended state observer(ESO)in active disturbance rejection controller(ADRC)is affected greatly by measurement noise when the control step is small in heading control of underwater flight vehicles(UFVs).In order to prevent rudder from high-frequency chattering caused by measurement noise,a tracking-differentiator(TD)is integrated to the ESO to develop an improved ADRC scheme.The improved ADRC suppresses the impact of sensor noise.Both the results of simulations and tank tests show the effectiveness of improved ADRC based heading control.展开更多
基金Supported by the National Natural Science Foundation of China (6 0 1 740 2 1 ) and Tianjin Key NaturalScience Foundation(0 1 3 80 0 71 1 )
文摘In this paper,some kinds of linear and nonlinear tracking-differentiators are designed by using suitable exponent functions instead of switch functions,and the stability of these tracking-differentiators is proved.From the result of simulations,it is manifest that the tracking speeds of these kinds of linear and nonlinear tracking-differentiators are very high,and their design procedures are simple.
基金Project(11226144) supported by the National Natural Science Foundation of China
文摘A filtering algorithm and direction identification method are presented for the positioning system of the mid-speed maglev train. Considering the special structure of the mid-speed maglev train, the ground position estimation method is adopted for its traction system. As the train is running, the induction loop-cable receives the signal sent by the on-board antenna to detect the position and direction of the train. But the height of the on-board antenna relative to the loop-cable is highly vulnerable to the change of the suspension height and the magnetic field produced by the traction during traveling, which may lead to amplitude fluctuation of the received signal. Consequently, the position estimation may be inaccurate. Therefore, a discrete second-order nonlinear trackdifferentiator is proposed based on the boundary characteristic curves, and the new differentiator could also extract the running direction of the train for the traction system. The experimental results show that the tracking differentiator can effectively filter out the signal interference and can provide accurate direction signal.
文摘The total disturbance estimated by the extended state observer(ESO)in active disturbance rejection controller(ADRC)is affected greatly by measurement noise when the control step is small in heading control of underwater flight vehicles(UFVs).In order to prevent rudder from high-frequency chattering caused by measurement noise,a tracking-differentiator(TD)is integrated to the ESO to develop an improved ADRC scheme.The improved ADRC suppresses the impact of sensor noise.Both the results of simulations and tank tests show the effectiveness of improved ADRC based heading control.
