The problem of fault detection for linear discrete timevarying systems with multiplicative noise is dealt with.By using an observer-based robust fault detection filter（FDF） as a residual generator,the design of the ...The problem of fault detection for linear discrete timevarying systems with multiplicative noise is dealt with.By using an observer-based robust fault detection filter（FDF） as a residual generator,the design of the FDF is formulated in the framework of H ∞ filtering for a class of stochastic time-varying systems.A sufficient condition for the existence of the FDF is derived in terms of a Riccati equation.The determination of the parameter matrices of the filter is converted into a quadratic optimization problem,and an analytical solution of the parameter matrices is obtained by solving the Riccati equation.Numerical examples are given to illustrate the effectiveness of the proposed method.展开更多
This paper deals with the problem of optimal fault detection filter （FDF） design for a class of discrete-time switched linear systems under arbitrary switching. By using an observer-based FDF as a residual generator...This paper deals with the problem of optimal fault detection filter （FDF） design for a class of discrete-time switched linear systems under arbitrary switching. By using an observer-based FDF as a residual generator, the design of the FDF is formulated into an optimization problem through maximizing the H_/H∞ or H∞/H∞ performance index. With the aid of an operator optimization method, it is shown that a mode-dependent unified optimal solution can be derived by solving a coupled Riccati equation. A numerical example is given to show the effectiveness of the proposed method.展开更多
Fringe projection profilometry has been increasingly sought and applied in dynamic three dimensional(3D)shape measurement.In this work,a robust,high-efficiency 3D measurement based on Gray-coded light is proposed.Unli...Fringe projection profilometry has been increasingly sought and applied in dynamic three dimensional(3D)shape measurement.In this work,a robust,high-efficiency 3D measurement based on Gray-coded light is proposed.Unlike the traditional method,a tripartite phase unwrapping method is proposed to avoid the jump errors on the boundary of code words,which are mainly caused by the defocusing of the projector and the motion of the tested object.Subsequently,the time overlapping coding strategy is presented to greatly increase the coding ef-ficiency,decreasing the projected number in each group from seven(i.e.,3+4)to four(i.e.,3+1)for one restored 3D frame.The combination of two proposed techniques allows the reconstruction of a pixel-wise and unambiguous 3D geometry of dynamic scenes with strong noise using every four projected patterns.To the best of our knowledge,the presented techniques for the first time preserve the high anti-noise ability of a method based on the Gray code while overcoming the drawbacks of jump errors and low coding efficiency.Experiments have demonstrated that the proposed method can achieve robust,high efficiency 3D shape measurement of high speed dynamic scenes even polluted by strong noise.展开更多
基金supported by the National Natural Science Foundation of China (61174121,61121003)the National High Technology Researchand Development Program of China (863 Program) (2008AA121302)+1 种基金the National Basic Research Program of China (973 Program)(2009CB724000)the Research Fund for the Doctoral Program of Higher Education of China
文摘The problem of fault detection for linear discrete timevarying systems with multiplicative noise is dealt with.By using an observer-based robust fault detection filter（FDF） as a residual generator,the design of the FDF is formulated in the framework of H ∞ filtering for a class of stochastic time-varying systems.A sufficient condition for the existence of the FDF is derived in terms of a Riccati equation.The determination of the parameter matrices of the filter is converted into a quadratic optimization problem,and an analytical solution of the parameter matrices is obtained by solving the Riccati equation.Numerical examples are given to illustrate the effectiveness of the proposed method.
基金supported by the National Natural Science Foundation of China(6117412161121003+2 种基金61203083)the Research Fund for the Doctoral Program of Higher Education of Chinathe Doctoral Foundation of University of Jinan(XBS1242)
文摘This paper deals with the problem of optimal fault detection filter （FDF） design for a class of discrete-time switched linear systems under arbitrary switching. By using an observer-based FDF as a residual generator, the design of the FDF is formulated into an optimization problem through maximizing the H_/H∞ or H∞/H∞ performance index. With the aid of an operator optimization method, it is shown that a mode-dependent unified optimal solution can be derived by solving a coupled Riccati equation. A numerical example is given to show the effectiveness of the proposed method.
基金National Natural Science Foundation of China(61675141).
文摘Fringe projection profilometry has been increasingly sought and applied in dynamic three dimensional(3D)shape measurement.In this work,a robust,high-efficiency 3D measurement based on Gray-coded light is proposed.Unlike the traditional method,a tripartite phase unwrapping method is proposed to avoid the jump errors on the boundary of code words,which are mainly caused by the defocusing of the projector and the motion of the tested object.Subsequently,the time overlapping coding strategy is presented to greatly increase the coding ef-ficiency,decreasing the projected number in each group from seven(i.e.,3+4)to four(i.e.,3+1)for one restored 3D frame.The combination of two proposed techniques allows the reconstruction of a pixel-wise and unambiguous 3D geometry of dynamic scenes with strong noise using every four projected patterns.To the best of our knowledge,the presented techniques for the first time preserve the high anti-noise ability of a method based on the Gray code while overcoming the drawbacks of jump errors and low coding efficiency.Experiments have demonstrated that the proposed method can achieve robust,high efficiency 3D shape measurement of high speed dynamic scenes even polluted by strong noise.
