The Experts below are selected from a list of 102618 Experts worldwide ranked by ideXlab platform
Miroslav Krstic - One of the best experts on this subject based on the ideXlab platform.
-
delay compensated control of sandwiched ode PDE ode hyperbolic systems for oil drilling and disaster relief
Automatica, 2020Co-Authors: Ji Wang, Miroslav KrsticAbstract:Abstract Motivated by engineering applications of subsea installation by deepwater construction vessels in oil drilling, and of aid delivery by unmanned aerial vehicles in disaster relief, we develop output-feedback boundary control of heterodirectional coupled hyperbolic PDEs sandwiched between two ODEs, where the measurement is the output state of one ODE and suffers a time delay. After rewriting the time-delay dynamics as a transport PDE of which the left boundary connects with the sandwiched system, a state observer is built to estimate the states of the overall system of ODE-heterodirectional coupled hyperbolic PDEs–ODE–transport PDE using the right boundary state of the last transport PDE. An observer-based output-feedback controller acting at the first ODE is designed to stabilize the overall system using backstepping transformations and frequency-domain designs. The exponential stability results of the closed-loop system, boundedness and exponential convergence of the control input are proved. The obtained theoretical result is applied to control of a deepwater oil drilling construction vessel as a simulation case, where the simulation results show the proposed control design reduces cable oscillations and places the oil drilling equipment to be installed in the target area on the sea floor. Performance deterioration under extreme and unmodeled disturbances is also illustrated.
-
single boundary control of the two phase stefan system
Systems & Control Letters, 2020Co-Authors: Shumon Koga, Miroslav KrsticAbstract:Abstract This paper presents the control design of the two-phase Stefan problem. The two-phase Stefan problem is a representative model of liquid–solid phase transition by describing the time evolutions of the temperature profile, which is divided by subdomains of liquid and solid phases as the liquid–solid moving interface position. The mathematical formulation is given by two diffusion partial differential equations (PDEs) defined on a time-varying spatial domain described by an ordinary differential equation (ODE) driven by the Neumann boundary values of both PDE states, resulting in a nonlinear coupled PDE–ODE–PDE system. We design a state feedback control law by means of energy-shaping to stabilize the interface position to a desired setpoint by using single boundary heat input. We prove that the closed-loop system under the control law ensures some conditions for model validity, and the global exponential stability estimate is shown in the spatial L 2 norm. Furthermore, the robustness of the closed-loop stability with respect to the uncertainties of the physical parameters is shown. Numerical simulation is provided to illustrate the desired performance of the proposed control law in comparison to the control design for the one-phase Stefan problem.
-
two phase stefan problem
2020Co-Authors: Shumon Koga, Miroslav KrsticAbstract:While in Sect. 4.4 we already dealt with an approximation of the influence of the solid phase, where non-monotonic interface dynamics arose due to incorporating a heat loss at the interface in the one-phase Stefan model, such a heat loss should be exactly modeled by a PDE for the solid phase and with the effect of the heat flux from the solid phase on the interface ODE. The control design to asymptotically stabilize the resulting PDE-ODE-PDE system is quite challenging. We present it in this chapter.
-
observer design for a coupled ode PDE system from a wellbore reservoir drilling model
Conference on Decision and Control, 2019Co-Authors: Leobardo Camachosolorio, Naveen Velmurugan, Florent Di Meglio, Miroslav KrsticAbstract:The problem of state estimation for a coupled ODE-PDE system is addressed here by means of the backstepping method for PDEs. The ODE is a finite-dimensional, linear time-invariant system and the PDE is a linear radial diffusion equation with Neumann and Robin boundary conditions. The coupling appears at one of the boundaries of the PDE and is bidirectional. More precisely, the ODE state appears in one of the boundary conditions of the PDE and the value of the PDE state at the boundary is an input to the ODE. Measurements of the ODE output are available, while the state of the PDE is out of sight. The estimate is defined as the state of an observer; constructed as a copy of the coupled system ODE-PDE with output error feedback. This study is motivated by the influx estimation problem from a wellbore-reservoir model used in managed pressured drilling applications.
-
delay compensated control of sandwiched ode PDE ode hyperbolic systems for oil drilling and disaster relief
arXiv: Optimization and Control, 2019Co-Authors: Ji Wang, Miroslav KrsticAbstract:Motivated by engineering applications of subsea installation by deepwater construction vessels in oil drilling, and of aid delivery by unmanned aerial vehicles in disaster relief, we develop output-feedback boundary control of heterodirectional coupled hyperbolic PDEs sandwiched between two general ODEs, where the measurement is the output state of one ODE and suffers a time delay. After rewriting the time-delay dynamics as a transport PDE of which the left boundary connects with the sandwiched system, a state observer is built to estimate the states of the overall system of ODE-heterodirectional coupled hyperbolic PDEs-ODE-transport PDE using the right boundary state of the last transport PDE. An observer-based output-feedback controller acting at the first ODE is designed to stabilize the overall system using backstepping transformations and frequency-domain designs. The exponential stability results of the closed-loop system, boundedness and exponential convergence of the control input are proved. The obtained theoretical result is applied to control of a deepwater oil drilling construction vessel as a simulation case, where the simulation results show the proposed control design reduces cable oscillations and places the oil drilling equipment to be installed in the target area on the sea floor. Performance deterioration under extreme and unmodelled disturbances is also illustrated.
M M Aghdam - One of the best experts on this subject based on the ideXlab platform.
-
thermo mechanical buckling and nonlinear free vibration analysis of functionally graded beams on nonlinear elastic foundation
Composites Part B-engineering, 2012Co-Authors: Ali Fallah, M M AghdamAbstract:Abstract In this paper, thermo-mechanical buckling and nonlinear free vibration analysis of functionally graded (FG) beams on nonlinear elastic foundation are investigated. Nonlinear governing partial differential equation (PDE) of motion is derived based on Euler–Bernoulli assumptions together with Von Karman strain–displacement relation. Based on the Galerkin’s decomposition method, the nonlinear PDE governing equation is reduced to a nonlinear ordinary differential equation (ODE). He’s variational method is employed to obtain a simple and efficient approximate closed form solution for the resulted nonlinear ODE. Comparison between results of the present work and those available in literature shows accuracy of the presented expressions. Some new results for the thermo-mechanical buckling and nonlinear free vibration analysis of the FG beams such as the effects of vibration amplitude, material inhomogeneity, nonlinear elastic foundation, boundary conditions, geometric parameter and thermal loading are presented to be used in future references.
-
thermo mechanical buckling and nonlinear free vibration analysis of functionally graded beams on nonlinear elastic foundation
Composites Part B-engineering, 2012Co-Authors: Ali Fallah, M M AghdamAbstract:Abstract In this paper, thermo-mechanical buckling and nonlinear free vibration analysis of functionally graded (FG) beams on nonlinear elastic foundation are investigated. Nonlinear governing partial differential equation (PDE) of motion is derived based on Euler–Bernoulli assumptions together with Von Karman strain–displacement relation. Based on the Galerkin’s decomposition method, the nonlinear PDE governing equation is reduced to a nonlinear ordinary differential equation (ODE). He’s variational method is employed to obtain a simple and efficient approximate closed form solution for the resulted nonlinear ODE. Comparison between results of the present work and those available in literature shows accuracy of the presented expressions. Some new results for the thermo-mechanical buckling and nonlinear free vibration analysis of the FG beams such as the effects of vibration amplitude, material inhomogeneity, nonlinear elastic foundation, boundary conditions, geometric parameter and thermal loading are presented to be used in future references.
Chengkang Xie - One of the best experts on this subject based on the ideXlab platform.
-
control law in analytic expression of a system coupled by reaction diffusion equation
Systems & Control Letters, 2020Co-Authors: Xinglan Liu, Chengkang XieAbstract:Abstract Control design of a coupled ODE–PDE boundary control system is considered in this paper. The PDE is one dimensional reaction–diffusion equation, with constant parameters, actuated at one of the boundaries and coupled to a linear and time-invariant ODE at the opposite boundary. By introducing a two-step backstepping design procedure, analytic solutions of the kernel and vector-valued functions in the backstepping transformations are obtained. Therefore, a boundary control law in analytic expression is constructed for this coupled ODE–PDE control system.
-
stabilization for a coupled PDE ode control system
Journal of The Franklin Institute-engineering and Applied Mathematics, 2011Co-Authors: Shuxia Tang, Chengkang XieAbstract:A control system of an ODE and a diffusion PDE is discussed in this paper. The novelty lies in that the system is coupled. The method of PDE backstepping as well as some special skills is resorted in stabilizing the coupled PDE–ODE control system, which is transformed into an exponentially stable PDE–ODE cascade with an invertible integral transformation. And a state feedback boundary controller is designed. Moreover, an exponentially convergent observer for anti-collocated setup is proposed, and the output feedback boundary control problem is solved. For both the state and output feedback boundary controllers, exponential stability analyses in the sense of the corresponding norms for the resulting closed-loop systems are given through rigid proofs.
-
state and output feedback boundary control for a coupled PDE ode system
Systems & Control Letters, 2011Co-Authors: Shuxia Tang, Chengkang XieAbstract:Abstract This note is devoted to stabilizing a coupled PDE–ODE system with interaction at the interface. First, a state feedback boundary controller is designed, and the system is transformed into an exponentially stable PDE–ODE cascade with an invertible integral transformation, where PDE backstepping is employed. Moreover, the solution to the resulting closed-loop system is derived explicitly. Second, an observer is proposed, which is proved to exhibit good performance in estimating the original coupled system, and then an output feedback boundary controller is obtained. For both the state and output feedback boundary controllers, exponential stability analyses in the sense of the corresponding norms for the resulting closed-loop systems are provided. The boundary controller and observer for a scalar coupled PDE–ODE system as well as the solutions to the closed-loop systems are given explicitly.
P Korytar - One of the best experts on this subject based on the ideXlab platform.
-
retention time database of 126 polybrominated diphenyl ether congeners and two bromkal technical mixtures on seven capillary gas chromatographic columns
Journal of Chromatography A, 2005Co-Authors: Adrian Covaci, P Korytar, Jacob De Boer, Anke Gelbin, Udo Th A BrinkmanAbstract:The elution order of 126 polybrominated diphenyl ethers (PBDE) was determined for seven different gas chromatographic (GC) stationary phases. The resulting database facilitates selection of the most suitable GC columns for developing a quantitative, congener-specific BDE analysis and the testing of retention prediction algorithms based on structure relationships of GC phases and congener substitution patterns. In addition, co-elutions of the principal BDE congeners with other BDEs and/or with other brominated flame retardants were investigated and, as an application, the composition of two Bromkal mixtures (70-5DE and 79-8DE) was studied.
Ji Wang - One of the best experts on this subject based on the ideXlab platform.
-
delay compensated control of sandwiched ode PDE ode hyperbolic systems for oil drilling and disaster relief
Automatica, 2020Co-Authors: Ji Wang, Miroslav KrsticAbstract:Abstract Motivated by engineering applications of subsea installation by deepwater construction vessels in oil drilling, and of aid delivery by unmanned aerial vehicles in disaster relief, we develop output-feedback boundary control of heterodirectional coupled hyperbolic PDEs sandwiched between two ODEs, where the measurement is the output state of one ODE and suffers a time delay. After rewriting the time-delay dynamics as a transport PDE of which the left boundary connects with the sandwiched system, a state observer is built to estimate the states of the overall system of ODE-heterodirectional coupled hyperbolic PDEs–ODE–transport PDE using the right boundary state of the last transport PDE. An observer-based output-feedback controller acting at the first ODE is designed to stabilize the overall system using backstepping transformations and frequency-domain designs. The exponential stability results of the closed-loop system, boundedness and exponential convergence of the control input are proved. The obtained theoretical result is applied to control of a deepwater oil drilling construction vessel as a simulation case, where the simulation results show the proposed control design reduces cable oscillations and places the oil drilling equipment to be installed in the target area on the sea floor. Performance deterioration under extreme and unmodeled disturbances is also illustrated.
-
Delay-Compensated Control of Sandwiched ODE-PDE-ODE Hyperbolic Systems for Oil Drilling and Disaster Relief
2020Co-Authors: Ji Wang, Krstic MiroslavAbstract:Motivated by engineering applications of subsea installation by deepwater construction vessels in oil drilling, and of aid delivery by unmanned aerial vehicles in disaster relief, we develop output-feedback boundary control of heterodirectional coupled hyperbolic PDEs sandwiched between two ODEs, where the measurement is the output state of one ODE and suffers a time delay. After rewriting the time-delay dynamics as a transport PDE of which the left boundary connects with the sandwiched system, a state observer is built to estimate the states of the overall system of ODE-heterodirectional coupled hyperbolic PDEs-ODE-transport PDE using the right boundary state of the last transport PDE. An observer-based output-feedback controller acting at the first ODE is designed to stabilize the overall system using backstepping transformations and frequency-domain designs. The exponential stability results of the closed-loop system, boundedness and exponential convergence of the control input are proved. The obtained theoretical result is applied to control of a deepwater oil drilling construction vessel as a simulation case, where the simulation results show the proposed control design reduces cable oscillations and places the oil drilling equipment to be installed in the target area on the sea floor. Performance deterioration under extreme and unmodeled disturbances is also illustrated.Comment: Supplementary document of the paper "Delay-compensated control of sandwiched ODE-PDE-ODE hyperbolic systems for oil drilling and disaster relief
-
delay compensated control of sandwiched ode PDE ode hyperbolic systems for oil drilling and disaster relief
arXiv: Optimization and Control, 2019Co-Authors: Ji Wang, Miroslav KrsticAbstract:Motivated by engineering applications of subsea installation by deepwater construction vessels in oil drilling, and of aid delivery by unmanned aerial vehicles in disaster relief, we develop output-feedback boundary control of heterodirectional coupled hyperbolic PDEs sandwiched between two general ODEs, where the measurement is the output state of one ODE and suffers a time delay. After rewriting the time-delay dynamics as a transport PDE of which the left boundary connects with the sandwiched system, a state observer is built to estimate the states of the overall system of ODE-heterodirectional coupled hyperbolic PDEs-ODE-transport PDE using the right boundary state of the last transport PDE. An observer-based output-feedback controller acting at the first ODE is designed to stabilize the overall system using backstepping transformations and frequency-domain designs. The exponential stability results of the closed-loop system, boundedness and exponential convergence of the control input are proved. The obtained theoretical result is applied to control of a deepwater oil drilling construction vessel as a simulation case, where the simulation results show the proposed control design reduces cable oscillations and places the oil drilling equipment to be installed in the target area on the sea floor. Performance deterioration under extreme and unmodelled disturbances is also illustrated.
-
output feedback boundary control of a heat PDE sandwiched between two odes
IEEE Transactions on Automatic Control, 2019Co-Authors: Ji Wang, Miroslav KrsticAbstract:We present designs for exponential stabilization of an ordinary differential equation (ODE)-heat partial differential equation (PDE)-ODE coupled system where the control actuation only acts in one ODE. The combination of PDE backstepping and ODE backstepping is employed in a state feedback control law and in an observer that estimates PDE and two ODE states using only one PDE boundary measurement. Based on the state feedback control law and the observer, the output feedback control law is then proposed. The exponential stability of the closed-loop system and the boundedness and exponential convergence of the control law are proved via Lyapunov analysis. Finally, numerical simulations validate the effectiveness of this method for the “sandwiched” system.
-
output feedback boundary control of a heat PDE sandwiched between two odes
arXiv: Optimization and Control, 2019Co-Authors: Ji Wang, Miroslav KrsticAbstract:We present designs for exponential stabilization of an ODE-heat PDE-ODE coupled system where the control actuation only acts in one ODE. The combination of PDE backstepping and ODE backstepping is employed in a state-feedback control law and in an observer that estimates PDE and two ODE states only using one PDE boundary measurement. Based on the state-feedback control law and the observer, the output-feedback control law is then proposed. The exponential stability of the closed-loop system and the boundedness and exponential convergence of the control law are proved via Lyapunov analysis. Finally, numerical simulations validate the effectiveness of this method for the `sandwiched' system.