This paper considers robust fault detection and diagnosis for input uncertain nonlinear systems. It proposes a multi-objective fault detection criterion so that the fault residual is sensitive to the fault but insensi...This paper considers robust fault detection and diagnosis for input uncertain nonlinear systems. It proposes a multi-objective fault detection criterion so that the fault residual is sensitive to the fault but insensitive to the uncertainty as much as possible. Then the paper solves the proposed criterion by maximizing the smallest singular value of the transformation from faults to fault detection residuals while minimizing the largest singular value of the transformation from input uncertainty to the fault detection residuals. This method is applied to an aircraft which has a fault in the left elevator or rudder. The simulation results show the proposed method can detect the control surface failures rapidly and efficiently.展开更多
The hysteresis nonlinearity of giant magnetostrictive actuator(GMA) is stress-dependent.In this paper,laboratory experiments were performed to characterize the stress-dependent hysteresis properties of a GMA under dif...The hysteresis nonlinearity of giant magnetostrictive actuator(GMA) is stress-dependent.In this paper,laboratory experiments were performed to characterize the stress-dependent hysteresis properties of a GMA under different compressive stresses ranging from ?11.3 MPa to ?24.3 MPa and harmonic current excitation with amplitudes from 0.6 A to 1.2 A.The experimental results showed that remarkable changes in peak-peak displacement responses,hysteresis loop width and hysteresis loss occurred with the increasing of compressive stress;no significant changes in coercive current were observed.Based on the analysis of experimental data and discussion of the influences of the weights of Modified Prandtl-Ishlinskii(MPI) on the characteristics of hysteresis loops,a stress-dependent Prandtl-Ishlinskii(SDPI) model was proposed by extending the MPI model to describe the effects of compressive stress,in which the weights of deadzone operators are extended as function of compressive stress.Good agreements were obtained between the model simulation results and the experimental data.Additional model validations were given by the performances of tracking control experiments with an inverse feedforward controller.The experimental results have clearly shown that the inverse SDPI is effective for compensating stress-dependent hysteresis including major and minor loops.展开更多
基金supported by the National Natural Science Foundation of China(60328304)the"111"project of Beihang University (B07009)
文摘This paper considers robust fault detection and diagnosis for input uncertain nonlinear systems. It proposes a multi-objective fault detection criterion so that the fault residual is sensitive to the fault but insensitive to the uncertainty as much as possible. Then the paper solves the proposed criterion by maximizing the smallest singular value of the transformation from faults to fault detection residuals while minimizing the largest singular value of the transformation from input uncertainty to the fault detection residuals. This method is applied to an aircraft which has a fault in the left elevator or rudder. The simulation results show the proposed method can detect the control surface failures rapidly and efficiently.
基金supported by the National Natural Science Foundation of China (Grant Nos. 91016006 and 91116002)the Fundamental Research Funds for the Central Universities
文摘The hysteresis nonlinearity of giant magnetostrictive actuator(GMA) is stress-dependent.In this paper,laboratory experiments were performed to characterize the stress-dependent hysteresis properties of a GMA under different compressive stresses ranging from ?11.3 MPa to ?24.3 MPa and harmonic current excitation with amplitudes from 0.6 A to 1.2 A.The experimental results showed that remarkable changes in peak-peak displacement responses,hysteresis loop width and hysteresis loss occurred with the increasing of compressive stress;no significant changes in coercive current were observed.Based on the analysis of experimental data and discussion of the influences of the weights of Modified Prandtl-Ishlinskii(MPI) on the characteristics of hysteresis loops,a stress-dependent Prandtl-Ishlinskii(SDPI) model was proposed by extending the MPI model to describe the effects of compressive stress,in which the weights of deadzone operators are extended as function of compressive stress.Good agreements were obtained between the model simulation results and the experimental data.Additional model validations were given by the performances of tracking control experiments with an inverse feedforward controller.The experimental results have clearly shown that the inverse SDPI is effective for compensating stress-dependent hysteresis including major and minor loops.
