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Ajouter le résultat dans votre panierTrajectory control of miniature helicopters using a unified nonlinear optimal control technique / Ming Xin in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 133 N° 6 (Novembre 2011)
Titre : Trajectory control of miniature helicopters using a unified nonlinear optimal control technique Type de document : texte imprimé Auteurs : Ming Xin, Auteur ; Yunjun Xu, Auteur ; Ricky Hopkins, Auteur Année de publication : 2012 Article en page(s) : 14 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Aircraft control Helicopters Mobile robots Motion Nonlinear systems Optimal Position Vehicle dynamics Index. décimale : 629.8 Résumé : It is always a challenge to design a real-time optimal full flight envelope controller for a miniature helicopter due to the nonlinear, underactuated, uncertain, and highly coupled nature of its dynamics. This paper integrates the control of translational, rotational, and flapping motions of a simulated miniature aerobatic helicopter in one unified optimal control framework. In particular, a recently developed real-time nonlinear optimal control method, called the theta-D technique, is employed to solve the resultant challenging problem considering the full nonlinear dynamics without gain scheduling techniques and timescale separations. The uniqueness of the theta-D method is its ability to obtain an approximate analytical solution to the Hamilton–Jacobi–Bellman equation, which leads to a closed-form suboptimal control law. As a result, it can provide a great advantage in real-time implementation without a high computational load. Two complex trajectory tracking scenarios are used to evaluate the control capabilities of the proposed method in full flight envelope. Realistic uncertainties in modeling parameters and the wind gust condition are included in the simulation for the purpose of demonstrating the robustness of the proposed control law. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 14 p.[article] Trajectory control of miniature helicopters using a unified nonlinear optimal control technique [texte imprimé] / Ming Xin, Auteur ; Yunjun Xu, Auteur ; Ricky Hopkins, Auteur . - 2012 . - 14 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 14 p.
Mots-clés : Aircraft control Helicopters Mobile robots Motion Nonlinear systems Optimal Position Vehicle dynamics Index. décimale : 629.8 Résumé : It is always a challenge to design a real-time optimal full flight envelope controller for a miniature helicopter due to the nonlinear, underactuated, uncertain, and highly coupled nature of its dynamics. This paper integrates the control of translational, rotational, and flapping motions of a simulated miniature aerobatic helicopter in one unified optimal control framework. In particular, a recently developed real-time nonlinear optimal control method, called the theta-D technique, is employed to solve the resultant challenging problem considering the full nonlinear dynamics without gain scheduling techniques and timescale separations. The uniqueness of the theta-D method is its ability to obtain an approximate analytical solution to the Hamilton–Jacobi–Bellman equation, which leads to a closed-form suboptimal control law. As a result, it can provide a great advantage in real-time implementation without a high computational load. Two complex trajectory tracking scenarios are used to evaluate the control capabilities of the proposed method in full flight envelope. Realistic uncertainties in modeling parameters and the wind gust condition are included in the simulation for the purpose of demonstrating the robustness of the proposed control law. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Solution of the forward dynamics of a single-loop linkage using power series Type de document : texte imprimé Auteurs : Paul Milenkovic, Auteur Année de publication : 2012 Article en page(s) : 09 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Differential equations Robot dynamics kinematics Series (mathematics) Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : The kinematic differential equations express the paths taken by points, lines, and coordinate frames attached to a rigid body in terms of the instantaneous screw for the motion of that body. Such differential equations are linear but with a time-varying coefficient and hence solvable by power series. A single-loop kinematic chain may be expressed by a system of such differential equations subject to a linear constraint. A single matrix factorization followed by a sequence of substitutions of linear-system right-hand-side terms determines successive orders of the joint rate coefficients in the kinematic solution for this mechanism. The present work extends this procedure to the forward dynamics problem, applying it to a Clemens constant-velocity coupling expressed as a spatial 9R closed kinematic chain. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 09 p.[article] Solution of the forward dynamics of a single-loop linkage using power series [texte imprimé] / Paul Milenkovic, Auteur . - 2012 . - 09 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 09 p.
Mots-clés : Differential equations Robot dynamics kinematics Series (mathematics) Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : The kinematic differential equations express the paths taken by points, lines, and coordinate frames attached to a rigid body in terms of the instantaneous screw for the motion of that body. Such differential equations are linear but with a time-varying coefficient and hence solvable by power series. A single-loop kinematic chain may be expressed by a system of such differential equations subject to a linear constraint. A single matrix factorization followed by a sequence of substitutions of linear-system right-hand-side terms determines successive orders of the joint rate coefficients in the kinematic solution for this mechanism. The present work extends this procedure to the forward dynamics problem, applying it to a Clemens constant-velocity coupling expressed as a spatial 9R closed kinematic chain. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Active steering assistance for lane keeping and lane departure prevention Type de document : texte imprimé Auteurs : Nicoleta Minoiu Enache, Auteur ; Saïd Mammar, Auteur ; Benoit Lusetti, Auteur Année de publication : 2012 Article en page(s) : 12 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Collision avoidance Control system synthesis Linear matrix inequalities Optimisation Road accidents vehicles Steering systems Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Single-vehicle road departure accidents represent a substantial amount of today's accidents. This paper presents the design and experimental test of an active steering assistance system that offers two functions: lane departure avoidance by temporary activation and maintaining vehicle heading by permanent activation. Each of the two functions can be used exclusively or in combination. Specific constraints related to each of the two functions are taken into account in the control design of the steering assistance by using LMI (linear matrix inequality) and BMI (bilinear matrix inequality) optimization methods. Consequently, lane overshoot is minimized for assistance activations near the border of the lane even during curve negotiation and robust lane keeping is ensured. Furthermore, the effects on lane keeping performance of simultaneous steering by the driver and the assistance are theoretically quantified. The results are verified using a fully equipped prototype vehicle. The obtained field test is consistent with the expected performance. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 12 p.[article] Active steering assistance for lane keeping and lane departure prevention [texte imprimé] / Nicoleta Minoiu Enache, Auteur ; Saïd Mammar, Auteur ; Benoit Lusetti, Auteur . - 2012 . - 12 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 12 p.
Mots-clés : Collision avoidance Control system synthesis Linear matrix inequalities Optimisation Road accidents vehicles Steering systems Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Single-vehicle road departure accidents represent a substantial amount of today's accidents. This paper presents the design and experimental test of an active steering assistance system that offers two functions: lane departure avoidance by temporary activation and maintaining vehicle heading by permanent activation. Each of the two functions can be used exclusively or in combination. Specific constraints related to each of the two functions are taken into account in the control design of the steering assistance by using LMI (linear matrix inequality) and BMI (bilinear matrix inequality) optimization methods. Consequently, lane overshoot is minimized for assistance activations near the border of the lane even during curve negotiation and robust lane keeping is ensured. Furthermore, the effects on lane keeping performance of simultaneous steering by the driver and the assistance are theoretically quantified. The results are verified using a fully equipped prototype vehicle. The obtained field test is consistent with the expected performance. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Auto-calibration based control and its application to a kind of electrohydraulic poppet valves Type de document : texte imprimé Auteurs : Patrick Opdenbosch, Auteur ; Nader Sadegh, Auteur ; Wayne Book, Auteur Année de publication : 2012 Article en page(s) : 10 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Adaptive control Electrohydraulic equipment Feedforward Inverse problems Position Pressure Valves Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : This paper describes a novel learning/adaptive state trajectory control method and its application to electronic hydraulic pressure control. The control algorithm presented herein learns the inverse input-state mapping of the plant at the same time this map is employed in the feedforward loop to force the state of the plant to asymptotically converge to a prescribed state trajectory. The algorithm accomplishes this task without requiring prior exact information about the state transition map of the plant. The novel controller is applied to an electrohydraulic poppet valve with the objective of tracking a desired supply pressure signal. In this application, the controller learns the inverse conductance characteristics of the valve. The supply pressure tracking performance subject to the proposed controller is validated through experimental data. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.[article] Auto-calibration based control and its application to a kind of electrohydraulic poppet valves [texte imprimé] / Patrick Opdenbosch, Auteur ; Nader Sadegh, Auteur ; Wayne Book, Auteur . - 2012 . - 10 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.
Mots-clés : Adaptive control Electrohydraulic equipment Feedforward Inverse problems Position Pressure Valves Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : This paper describes a novel learning/adaptive state trajectory control method and its application to electronic hydraulic pressure control. The control algorithm presented herein learns the inverse input-state mapping of the plant at the same time this map is employed in the feedforward loop to force the state of the plant to asymptotically converge to a prescribed state trajectory. The algorithm accomplishes this task without requiring prior exact information about the state transition map of the plant. The novel controller is applied to an electrohydraulic poppet valve with the objective of tracking a desired supply pressure signal. In this application, the controller learns the inverse conductance characteristics of the valve. The supply pressure tracking performance subject to the proposed controller is validated through experimental data. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Physical limitations for the bandwidth frequency of a pressure controlled, axial-piston pump Type de document : texte imprimé Auteurs : Manring, Noah D., Auteur ; Mehta, Viral S., Auteur Année de publication : 2012 Article en page(s) : 12 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Design engineering Hydraulic actuators Perturbation techniques Pistons Pressure control Pumps Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : The objectives of this paper are to identify the design parameters that have the greatest impact on the bandwidth frequency of a pressure controlled, axial-piston pump. This study is motivated by the fact that a physical limitation for these machines has been observed in practice, as it has been difficult to increase the bandwidth frequency much beyond 25 Hz. Though much research has been done over the past thirty years to understand the dynamical behavior of these machines, the essential design-characteristics that determine the bandwidth frequency of the pump remain elusive. In part, this is due to the fact that the machine is complex and when coupled with a hydraulic control valve that is disturbed by steady and transient fluid-momentum effects this dynamical property becomes difficult to assess. In order to achieve the objectives of this research, this paper presents the most comprehensive pump-and-valve model of a pressure controlled, axial-piston machine available in the literature to date. The pump model includes the effects of the discrete pumping-elements acting on the swash plate, while the valve model includes both steady and transient fluid-momentum forces. To identify the dominate features of the model, nondimensional analysis is employed and the complexity of the model is subsequently reduced by eliminating negligible terms. Furthermore, a closed-form expression for the bandwidth frequency is employed and perturbation analysis is used to identify the dominant set of parameters that impact the bandwidth frequency of the pump. In conclusion, it is shown that, by far, the greatest impact on the bandwidth frequency may be achieved by reducing the swept volume of the control actuator and by increasing the flow capacity of the control valve. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 12 p.[article] Physical limitations for the bandwidth frequency of a pressure controlled, axial-piston pump [texte imprimé] / Manring, Noah D., Auteur ; Mehta, Viral S., Auteur . - 2012 . - 12 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 12 p.
Mots-clés : Design engineering Hydraulic actuators Perturbation techniques Pistons Pressure control Pumps Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : The objectives of this paper are to identify the design parameters that have the greatest impact on the bandwidth frequency of a pressure controlled, axial-piston pump. This study is motivated by the fact that a physical limitation for these machines has been observed in practice, as it has been difficult to increase the bandwidth frequency much beyond 25 Hz. Though much research has been done over the past thirty years to understand the dynamical behavior of these machines, the essential design-characteristics that determine the bandwidth frequency of the pump remain elusive. In part, this is due to the fact that the machine is complex and when coupled with a hydraulic control valve that is disturbed by steady and transient fluid-momentum effects this dynamical property becomes difficult to assess. In order to achieve the objectives of this research, this paper presents the most comprehensive pump-and-valve model of a pressure controlled, axial-piston machine available in the literature to date. The pump model includes the effects of the discrete pumping-elements acting on the swash plate, while the valve model includes both steady and transient fluid-momentum forces. To identify the dominate features of the model, nondimensional analysis is employed and the complexity of the model is subsequently reduced by eliminating negligible terms. Furthermore, a closed-form expression for the bandwidth frequency is employed and perturbation analysis is used to identify the dominant set of parameters that impact the bandwidth frequency of the pump. In conclusion, it is shown that, by far, the greatest impact on the bandwidth frequency may be achieved by reducing the swept volume of the control actuator and by increasing the flow capacity of the control valve. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Model-based control of the air fuel ratio for gasoline direct injection engines via advanced co-simulation : an approach to reduce the development cycle of engine control systems Type de document : texte imprimé Auteurs : Alessandro di Gaeta, Auteur ; Umberto Montanaro, Auteur ; Veniero Giglio, Auteur Année de publication : 2012 Article en page(s) : 17 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Control system synthesis Gain control Internal combustion engines PI Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Nowadays, the precise control of the air fuel ratio (AFR) in spark ignition (SI) engines plays a crucial role in meeting the more and more restrictive standard emissions for the passenger cars and the fuel economy required by the automotive market as well. To attain this demanding goal, the development of an advanced AFR control strategy embedding highly predictive models becomes mandatory for the next generation of electronic control unit (ECU). Conversely, the adoption of more complex control strategies affects the development time of the ECU increasing the time-to-market of new engine models. In this paper to solve the AFR control problem for gasoline direct injection (GDI) and to speed up the design of the entire control system, a gain scheduling PI model-based control strategy is proposed. To this aim, AFR dynamics are modeled via a first order time delay system whose parameters vary strongly with the fresh air mass entering the cylinders. Nonlinear relations have been found to describe the behavior of model parameters in function of air mass. Closed loop performances, when this novel controller is nested in the control loop, are compared to those provided by the classical PI Ziegler–Nichols control action with respect to different cost functions. Model validation as well as the effectiveness of the control design are carried out by means of ECU-1D engine co-simulation environment for a wide range of engine working conditions. The combination in one integrated designing environment of control systems and virtual engine, simulated through high predictive commercial one dimensional code, becomes a high predictive tool for automotive control engineers and enables fast prototyping. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 17 p.[article] Model-based control of the air fuel ratio for gasoline direct injection engines via advanced co-simulation : an approach to reduce the development cycle of engine control systems [texte imprimé] / Alessandro di Gaeta, Auteur ; Umberto Montanaro, Auteur ; Veniero Giglio, Auteur . - 2012 . - 17 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 17 p.
Mots-clés : Control system synthesis Gain control Internal combustion engines PI Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Nowadays, the precise control of the air fuel ratio (AFR) in spark ignition (SI) engines plays a crucial role in meeting the more and more restrictive standard emissions for the passenger cars and the fuel economy required by the automotive market as well. To attain this demanding goal, the development of an advanced AFR control strategy embedding highly predictive models becomes mandatory for the next generation of electronic control unit (ECU). Conversely, the adoption of more complex control strategies affects the development time of the ECU increasing the time-to-market of new engine models. In this paper to solve the AFR control problem for gasoline direct injection (GDI) and to speed up the design of the entire control system, a gain scheduling PI model-based control strategy is proposed. To this aim, AFR dynamics are modeled via a first order time delay system whose parameters vary strongly with the fresh air mass entering the cylinders. Nonlinear relations have been found to describe the behavior of model parameters in function of air mass. Closed loop performances, when this novel controller is nested in the control loop, are compared to those provided by the classical PI Ziegler–Nichols control action with respect to different cost functions. Model validation as well as the effectiveness of the control design are carried out by means of ECU-1D engine co-simulation environment for a wide range of engine working conditions. The combination in one integrated designing environment of control systems and virtual engine, simulated through high predictive commercial one dimensional code, becomes a high predictive tool for automotive control engineers and enables fast prototyping. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Calculation of frequency response envelope for dynamic systems with uncertain parameters Type de document : texte imprimé Auteurs : Wen-Hua Chen, Auteur Année de publication : 2012 Article en page(s) : 09 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Closed loop systems Finite element analysis Frequency response Nonlinear control Open Transfer functions Uncertain Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Frequency response finds a wide range of applications in many engineering sectors. When variations and uncertainties exist during the operation and lifetime of an engineering system, the calculation of frequency response for an uncertain dynamic system is required in order to assess the worst cases in terms of various criteria, for example gain and phase margins in control engineering, or peak magnitude at different modes in the finite element analysis of structures. This paper describes an analytical approach toward the identification of critical interior lines that possibly contribute to the boundary of the frequency response. It is allowed that uncertain parameters perturb transfer function coefficients in a nonlinear form. Conditions for critical interior lines contributing to the boundary of the frequency response are presented. An invariant property of these critical lines under open-loop and closed-loop configurations augmented by control systems or compensators is established, which greatly simplifies the analysis, design, and verification process when using frequency domain techniques. A procedure for computing frequency response and identifying the worst cases is then developed based on the combination of symbolic and numerical computation. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 09 p.[article] Calculation of frequency response envelope for dynamic systems with uncertain parameters [texte imprimé] / Wen-Hua Chen, Auteur . - 2012 . - 09 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 09 p.
Mots-clés : Closed loop systems Finite element analysis Frequency response Nonlinear control Open Transfer functions Uncertain Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Frequency response finds a wide range of applications in many engineering sectors. When variations and uncertainties exist during the operation and lifetime of an engineering system, the calculation of frequency response for an uncertain dynamic system is required in order to assess the worst cases in terms of various criteria, for example gain and phase margins in control engineering, or peak magnitude at different modes in the finite element analysis of structures. This paper describes an analytical approach toward the identification of critical interior lines that possibly contribute to the boundary of the frequency response. It is allowed that uncertain parameters perturb transfer function coefficients in a nonlinear form. Conditions for critical interior lines contributing to the boundary of the frequency response are presented. An invariant property of these critical lines under open-loop and closed-loop configurations augmented by control systems or compensators is established, which greatly simplifies the analysis, design, and verification process when using frequency domain techniques. A procedure for computing frequency response and identifying the worst cases is then developed based on the combination of symbolic and numerical computation. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Identification of die thermal dynamics using neural networks Type de document : texte imprimé Auteurs : Jaho Seo, Auteur ; Khajepour, Amir, Auteur ; Huissoon, Jan Paul, Auteur Année de publication : 2012 Article en page(s) : 09 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Cooling Die casting Finite element analysis Mechanical engineering computing Neural nets Temperature distribution Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : The objective of this research is to identify a dynamic model that describes the temperature distribution in a die with uncertain dynamics using a neural network (NN) approach. By using data sets obtained from a finite element analysis (FEA) of the thermal dynamics of a die and applying NN off-line and on-line learning algorithms, the die model is identified. This identification approach has been conducted assuming fully measurable and partially measurable states. For the latter, a NN based adaptive observer is employed to estimate unmeasurable states. It is shown that the complex behavior of the die system with cooling channels can be accurately identified in both cases of fully and partially measurable states. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 09 p.[article] Identification of die thermal dynamics using neural networks [texte imprimé] / Jaho Seo, Auteur ; Khajepour, Amir, Auteur ; Huissoon, Jan Paul, Auteur . - 2012 . - 09 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 09 p.
Mots-clés : Cooling Die casting Finite element analysis Mechanical engineering computing Neural nets Temperature distribution Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : The objective of this research is to identify a dynamic model that describes the temperature distribution in a die with uncertain dynamics using a neural network (NN) approach. By using data sets obtained from a finite element analysis (FEA) of the thermal dynamics of a die and applying NN off-line and on-line learning algorithms, the die model is identified. This identification approach has been conducted assuming fully measurable and partially measurable states. For the latter, a NN based adaptive observer is employed to estimate unmeasurable states. It is shown that the complex behavior of the die system with cooling channels can be accurately identified in both cases of fully and partially measurable states. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Inverse dynamics of a redundantly actuated four-bar mechanism using an optimal control formulation Type de document : texte imprimé Auteurs : Olavo Luppi Silva, Auteur ; Menegaldo, Luciano Luporini, Auteur Année de publication : 2012 Article en page(s) : 10 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Actuators Matrix algebra Optimal control Robot dynamics kinematics Torque Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : This paper presents an approach to estimating joint torques in a four-bar closed-chain mechanism with prescribed kinematics and redundant actuation, i.e., with more actuators than degrees of freedom. This problem has several applications in industrial robots, machine tools, and biomechanics. The inverse dynamics problem is formulated as an optimal control problem (OCP). The dynamical equations are derived for an open-chain mechanism, what keeps the formulation simple and straightforward. Sets of constraints are explored to force the three-link open-chain to behave as a four-bar mechanism with a crank rotating at a constant velocity. The controls calculated from the OCP are assumed to be the input joint torques. The standard case with one torque actuator is solved and compared to cases with two and three actuators. The case of two actuators presented the smallest peak and mean torques, using one specific set of constraints. Such torques were smaller than the solution obtained using an alternative method existing in literature that solves the redundancy problem by means of the pseudo-inverse matrix. Comparison with inverse dynamics solutions using well-established methods for the one-actuator closed-loop four-bar were equal. Reconstructed kinematical trajectories from forward integration of the closed-loop mechanism with the OCP obtained torques were essentially similar. The results suggest that the adopted procedure is promising, giving solutions with lower torque requirements than the regularly actuated case and redundantly actuated computed with other approaches. The applicability of the method has been shown for the four-bar mechanism. Other classes of redundantly actuated, closed-loop mechanisms could be tested using a similar formulation. However, the numerical parameters of the OCP must be chosen carefully to achieve convergence. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.[article] Inverse dynamics of a redundantly actuated four-bar mechanism using an optimal control formulation [texte imprimé] / Olavo Luppi Silva, Auteur ; Menegaldo, Luciano Luporini, Auteur . - 2012 . - 10 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.
Mots-clés : Actuators Matrix algebra Optimal control Robot dynamics kinematics Torque Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : This paper presents an approach to estimating joint torques in a four-bar closed-chain mechanism with prescribed kinematics and redundant actuation, i.e., with more actuators than degrees of freedom. This problem has several applications in industrial robots, machine tools, and biomechanics. The inverse dynamics problem is formulated as an optimal control problem (OCP). The dynamical equations are derived for an open-chain mechanism, what keeps the formulation simple and straightforward. Sets of constraints are explored to force the three-link open-chain to behave as a four-bar mechanism with a crank rotating at a constant velocity. The controls calculated from the OCP are assumed to be the input joint torques. The standard case with one torque actuator is solved and compared to cases with two and three actuators. The case of two actuators presented the smallest peak and mean torques, using one specific set of constraints. Such torques were smaller than the solution obtained using an alternative method existing in literature that solves the redundancy problem by means of the pseudo-inverse matrix. Comparison with inverse dynamics solutions using well-established methods for the one-actuator closed-loop four-bar were equal. Reconstructed kinematical trajectories from forward integration of the closed-loop mechanism with the OCP obtained torques were essentially similar. The results suggest that the adopted procedure is promising, giving solutions with lower torque requirements than the regularly actuated case and redundantly actuated computed with other approaches. The applicability of the method has been shown for the four-bar mechanism. Other classes of redundantly actuated, closed-loop mechanisms could be tested using a similar formulation. However, the numerical parameters of the OCP must be chosen carefully to achieve convergence. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Supervisory control of parallel hybrid electric vehicles for fuel and emission reduction Type de document : texte imprimé Auteurs : Dongsuk Kum, Auteur ; Huei Peng, Auteur ; Norman K. Bucknor, Auteur Année de publication : 2012 Article en page(s) : 10 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Air pollution control Catalysis Dynamic programming Engines Exhaust systems Fuel economy Hybrid electric vehicles Minimisation Optimal Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Past research on hybrid electric vehicles (HEVs) focused primarily on improving their fuel economy. Emission reduction is another important performance attribute that needs to be addressed. When emissions are considered for hybrid vehicles with a gasoline engine, horizon-based optimization methodologies should be used because the light-off of the three-way catalytic converter heavily depends on the warming-up of catalyst temperature. In this paper, we propose a systematic design method for a cold-start supervisory control algorithm based on the dynamic programming (DP) methodology. First, a system-level parallel HEV model is developed to efficiently predict tailpipe emissions as well as fuel economy. The optimal control problem for minimization of cold-start emissions and fuel consumption is then solved via DP. Since DP solution cannot be directly implemented as a real-time controller, more useful control strategies are extracted from DP solutions over the entire state space via the comprehensive extraction method. The extracted DP results indicate that the engine on/off, gear-shift, and power-split strategies must be properly adjusted to achieve fast catalyst warm-up and low cold-start tailpipe emissions. Based on DP results, we proposed a rule-based control algorithm that is easy to implement and adjust while achieving near-optimal fuel economy and emission performance. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.[article] Supervisory control of parallel hybrid electric vehicles for fuel and emission reduction [texte imprimé] / Dongsuk Kum, Auteur ; Huei Peng, Auteur ; Norman K. Bucknor, Auteur . - 2012 . - 10 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.
Mots-clés : Air pollution control Catalysis Dynamic programming Engines Exhaust systems Fuel economy Hybrid electric vehicles Minimisation Optimal Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Past research on hybrid electric vehicles (HEVs) focused primarily on improving their fuel economy. Emission reduction is another important performance attribute that needs to be addressed. When emissions are considered for hybrid vehicles with a gasoline engine, horizon-based optimization methodologies should be used because the light-off of the three-way catalytic converter heavily depends on the warming-up of catalyst temperature. In this paper, we propose a systematic design method for a cold-start supervisory control algorithm based on the dynamic programming (DP) methodology. First, a system-level parallel HEV model is developed to efficiently predict tailpipe emissions as well as fuel economy. The optimal control problem for minimization of cold-start emissions and fuel consumption is then solved via DP. Since DP solution cannot be directly implemented as a real-time controller, more useful control strategies are extracted from DP solutions over the entire state space via the comprehensive extraction method. The extracted DP results indicate that the engine on/off, gear-shift, and power-split strategies must be properly adjusted to achieve fast catalyst warm-up and low cold-start tailpipe emissions. Based on DP results, we proposed a rule-based control algorithm that is easy to implement and adjust while achieving near-optimal fuel economy and emission performance. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Cellular stochastic control of the collective output of a class of distributed hysteretic systems Type de document : texte imprimé Auteurs : Levi B. Wood, Auteur ; Harry Asada, H., Auteur Année de publication : 2012 Article en page(s) : 11 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Distributed control Feedback Hysteresis Intelligent actuators Robust Shape memory effects Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Stable stochastic feedback control of an aggregate output from a multitude of cellular units is presented in this paper. Similar to a skeletal muscle comprising a number of muscle fibers, the plant considered in this paper consists of many independent units (called cellular units), each of which contributes to an aggregate output of the whole system. The central controller regulates the aggregate output by stochastically recruiting as many cellular units as needed for producing a required output. Two challenges are considered. The first is how to deal with individual units having pronounced hysteresis and long latency time in transient response. It will be shown that slow response and poor stability due to the hysteresis and latency time can significantly be improved by coordinating the multitude of cellular units, which are in diverse phases in the hysteresis loop. The second challenge is how to build a central controller that coordinates the multitude of cellular units without knowing the state of individual units. Stochastic broadcast feedback is presented as a solution that meets those requirements. The central controller observes only the aggregate output value rather than the output and state of each unit, compares the aggregate output against a reference, and broadcasts an error signal to all the units, which are anonymous. In turn, each cellular unit makes a control decision stochastically with state transition probabilities that are modulated by the broadcast error signal from the central controller. Stability analysis based on supermatingale theory guarantees that this stochastic broadcast feedback is stable and robust against cell failures. The method is applied to the control of shape-memory-alloy muscle actuators with cellular architecture. Despite pronounced hysteresis and long latency time, stochastic broadcast feedback can achieve fast and stable control. Simulation experiments verify the theoretical results. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 11 p.[article] Cellular stochastic control of the collective output of a class of distributed hysteretic systems [texte imprimé] / Levi B. Wood, Auteur ; Harry Asada, H., Auteur . - 2012 . - 11 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 11 p.
Mots-clés : Distributed control Feedback Hysteresis Intelligent actuators Robust Shape memory effects Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Stable stochastic feedback control of an aggregate output from a multitude of cellular units is presented in this paper. Similar to a skeletal muscle comprising a number of muscle fibers, the plant considered in this paper consists of many independent units (called cellular units), each of which contributes to an aggregate output of the whole system. The central controller regulates the aggregate output by stochastically recruiting as many cellular units as needed for producing a required output. Two challenges are considered. The first is how to deal with individual units having pronounced hysteresis and long latency time in transient response. It will be shown that slow response and poor stability due to the hysteresis and latency time can significantly be improved by coordinating the multitude of cellular units, which are in diverse phases in the hysteresis loop. The second challenge is how to build a central controller that coordinates the multitude of cellular units without knowing the state of individual units. Stochastic broadcast feedback is presented as a solution that meets those requirements. The central controller observes only the aggregate output value rather than the output and state of each unit, compares the aggregate output against a reference, and broadcasts an error signal to all the units, which are anonymous. In turn, each cellular unit makes a control decision stochastically with state transition probabilities that are modulated by the broadcast error signal from the central controller. Stability analysis based on supermatingale theory guarantees that this stochastic broadcast feedback is stable and robust against cell failures. The method is applied to the control of shape-memory-alloy muscle actuators with cellular architecture. Despite pronounced hysteresis and long latency time, stochastic broadcast feedback can achieve fast and stable control. Simulation experiments verify the theoretical results. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Fuzzy sliding mode control of rigid-flexible multibody systems with bounded inputs Type de document : texte imprimé Auteurs : Pinhas Ben-Tzvi, Auteur ; Shengjian Bai, Auteur ; Qingkun Zhou, Auteur Année de publication : 2012 Article en page(s) : 08 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Control system synthesis Flexible structures Fuzzy control Space vehicles Structural engineering Variable structure systems Vibration Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : This paper presents the dynamic modeling and fuzzy sliding mode control for rigid-flexible multibody systems. To investigate the dynamic stiffening of rigid-flexible systems, a first-order approximate model of a flexible spacecraft system is formulated by using Hamilton's principles and assumed mode method, taking into account the second-order term of the coupling deformation field. For highly flexible structural models, ideal surface sliding that produces pure rigid body motion may not be achievable. In this paper, the discontinuity in the sliding mode controller is smoothed inside a thin boundary layer using fuzzy logic technique to reduce the chattering phenomenon efficiently. Sliding mode control is insensitive to parameter variations and provides complete rejection of disturbances, but these advantages only hold in the sliding mode domain. However, when the actuators' amplitude is limited by their physical constraints, the sliding mode domain will be restricted to some local domain near zero on the switching surface. Control input saturation is also considered in the fuzzy sliding mode control approach. The new features and advantages of the proposed approach are the use of new dynamic equations for the motion of flexible spacecraft systems and the design of fuzzy sliding mode control by taking into account the control input saturation. The classical sliding mode control case is also developed for comparison. Numerical simulations are performed to validate the proposed methods and to demonstrate that rotational maneuvers and vibration suppression are accomplished in spite of the presence of model uncertainty and control saturation nonlinearity. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 08 p.[article] Fuzzy sliding mode control of rigid-flexible multibody systems with bounded inputs [texte imprimé] / Pinhas Ben-Tzvi, Auteur ; Shengjian Bai, Auteur ; Qingkun Zhou, Auteur . - 2012 . - 08 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 08 p.
Mots-clés : Control system synthesis Flexible structures Fuzzy control Space vehicles Structural engineering Variable structure systems Vibration Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : This paper presents the dynamic modeling and fuzzy sliding mode control for rigid-flexible multibody systems. To investigate the dynamic stiffening of rigid-flexible systems, a first-order approximate model of a flexible spacecraft system is formulated by using Hamilton's principles and assumed mode method, taking into account the second-order term of the coupling deformation field. For highly flexible structural models, ideal surface sliding that produces pure rigid body motion may not be achievable. In this paper, the discontinuity in the sliding mode controller is smoothed inside a thin boundary layer using fuzzy logic technique to reduce the chattering phenomenon efficiently. Sliding mode control is insensitive to parameter variations and provides complete rejection of disturbances, but these advantages only hold in the sliding mode domain. However, when the actuators' amplitude is limited by their physical constraints, the sliding mode domain will be restricted to some local domain near zero on the switching surface. Control input saturation is also considered in the fuzzy sliding mode control approach. The new features and advantages of the proposed approach are the use of new dynamic equations for the motion of flexible spacecraft systems and the design of fuzzy sliding mode control by taking into account the control input saturation. The classical sliding mode control case is also developed for comparison. Numerical simulations are performed to validate the proposed methods and to demonstrate that rotational maneuvers and vibration suppression are accomplished in spite of the presence of model uncertainty and control saturation nonlinearity. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Analysis and modeling of a pneumatic servo system based on backstepping design Type de document : texte imprimé Auteurs : Chia-Hua Lu, Auteur ; Yean-Ren Hwang, Auteur ; Yu-Ta Shen, Auteur Année de publication : 2012 Article en page(s) : 10 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Blades Control system synthesis Nonlinear control systems Pneumatic Servomechanisms Three-term Tracking Variable structure Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Air motors have often been utilized in industrial servo systems in the automation industry due to their advantages such as small volume, low cost, light weight, convenience of operation, and no overheating problems. Recently, the development of control technology has improved, making the requirements for control precision higher than ever before. Accurate control performance in pneumatic systems is facilitated by the implementation of nonlinear control techniques. The purpose of this study is to analyze the behavior of a biaxial pneumatic table motion system with a vane-type air motor, and to design a backstepping sliding mode controller for this system. A proportional integral derivative controller compared with this new backstepping design. The tracking circle error and tracking error of the two axes are noted. The experimental results show that accurate tracking circle trajectory performance can be achieved with the proposed controller. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.[article] Analysis and modeling of a pneumatic servo system based on backstepping design [texte imprimé] / Chia-Hua Lu, Auteur ; Yean-Ren Hwang, Auteur ; Yu-Ta Shen, Auteur . - 2012 . - 10 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.
Mots-clés : Blades Control system synthesis Nonlinear control systems Pneumatic Servomechanisms Three-term Tracking Variable structure Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Air motors have often been utilized in industrial servo systems in the automation industry due to their advantages such as small volume, low cost, light weight, convenience of operation, and no overheating problems. Recently, the development of control technology has improved, making the requirements for control precision higher than ever before. Accurate control performance in pneumatic systems is facilitated by the implementation of nonlinear control techniques. The purpose of this study is to analyze the behavior of a biaxial pneumatic table motion system with a vane-type air motor, and to design a backstepping sliding mode controller for this system. A proportional integral derivative controller compared with this new backstepping design. The tracking circle error and tracking error of the two axes are noted. The experimental results show that accurate tracking circle trajectory performance can be achieved with the proposed controller. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Position control of servomotors using neural dynamic sliding mode Type de document : texte imprimé Auteurs : A. Karami-Mollaee, Auteur ; N. Pariz, Auteur ; H. M. Shanechi, Auteur Année de publication : 2012 Article en page(s) : 10 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Adaptive control Learning (artificial intelligence) Machine Neurocontrollers Nonlinear systems PI Position Radial basis function networks Robust Servomotors State feedback Variable structure Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : In this paper, position control of servomotors is addressed. A radial basis function neural network is employed to identify the unknown nonlinear function of the plant model, and then a robust adaptive law is developed to train the parameters of the neural network, which does not require any preliminary off-line weight learning. Moreover, base on the identified model, we propose a new dynamic sliding mode control (DSMC) for a general class of nonaffine nonlinear systems by defining a new adaptive proportional-integral sliding surface and employing a linear state feedback. The main property of proposed controller is that it does not need an upper bound for the uncertainty and identified model; moreover, the switching gain increases and decreases according to the system circumstance by employing an adaptive procedure. Then, chattering is removed completely by using the DSMC with a small switching gain. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.[article] Position control of servomotors using neural dynamic sliding mode [texte imprimé] / A. Karami-Mollaee, Auteur ; N. Pariz, Auteur ; H. M. Shanechi, Auteur . - 2012 . - 10 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.
Mots-clés : Adaptive control Learning (artificial intelligence) Machine Neurocontrollers Nonlinear systems PI Position Radial basis function networks Robust Servomotors State feedback Variable structure Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : In this paper, position control of servomotors is addressed. A radial basis function neural network is employed to identify the unknown nonlinear function of the plant model, and then a robust adaptive law is developed to train the parameters of the neural network, which does not require any preliminary off-line weight learning. Moreover, base on the identified model, we propose a new dynamic sliding mode control (DSMC) for a general class of nonaffine nonlinear systems by defining a new adaptive proportional-integral sliding surface and employing a linear state feedback. The main property of proposed controller is that it does not need an upper bound for the uncertainty and identified model; moreover, the switching gain increases and decreases according to the system circumstance by employing an adaptive procedure. Then, chattering is removed completely by using the DSMC with a small switching gain. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Decentralized PID controllers based on probabilistic robustness Type de document : texte imprimé Auteurs : Chuanfeng Wang, Auteur ; Donghai Li, Auteur Année de publication : 2012 Article en page(s) : 08 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Chemical engineering Control system synthesis Decentralised control Genetic algorithms MIMO systems Monte Carlo methods Multivariable Probability Robust Three-term Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : A tuning method for decentralized PID controllers was developed based on probabilistic robustness for multi-input-multi-output plants, whose parameters vary in a determinate area. The advantage of this method is that the entire uncertainty parameter space can be considered for controller designing. According to model uncertainties, the probabilities of satisfaction for every item of dynamic performance requirements were computed and synthesized as the cost function of genetic algorithms, which was used to optimize the parameters of decentralized PID controllers. Monte Carlo experiments were used to test the control system robustness. Simulations for five multivariable chemical processes were carried out. Comparisons with a standard design method based on nominal conditions indicate that the method presented in this paper has better robustness, and the systems can satisfy the design requirements in a maximal probability. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 08 p.[article] Decentralized PID controllers based on probabilistic robustness [texte imprimé] / Chuanfeng Wang, Auteur ; Donghai Li, Auteur . - 2012 . - 08 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 08 p.
Mots-clés : Chemical engineering Control system synthesis Decentralised control Genetic algorithms MIMO systems Monte Carlo methods Multivariable Probability Robust Three-term Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : A tuning method for decentralized PID controllers was developed based on probabilistic robustness for multi-input-multi-output plants, whose parameters vary in a determinate area. The advantage of this method is that the entire uncertainty parameter space can be considered for controller designing. According to model uncertainties, the probabilities of satisfaction for every item of dynamic performance requirements were computed and synthesized as the cost function of genetic algorithms, which was used to optimize the parameters of decentralized PID controllers. Monte Carlo experiments were used to test the control system robustness. Simulations for five multivariable chemical processes were carried out. Comparisons with a standard design method based on nominal conditions indicate that the method presented in this paper has better robustness, and the systems can satisfy the design requirements in a maximal probability. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Friction hysteresis modeling and force control in a constrained single-link arm Type de document : texte imprimé Auteurs : Bazaei, Ali, Auteur ; M. Moallem, Auteur Année de publication : 2012 Article en page(s) : 09 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Force control Friction Hysteresis Manipulator dynamics Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : In this paper, we study friction characteristics of a constrained planar single-link arm in applications, where control of the end-point interaction force is required. The objective is to improve performance of a force control system by developing an adequate friction model. It is shown that hub friction increases with the applied force with the end-point force exhibiting significant hysteresis behavior. A friction model is presented for capturing these phenomena and compared with the widely used LuGre friction model. Effectiveness of the proposed model for friction compensation is further examined on an experimental force control system testbed. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 09 p.[article] Friction hysteresis modeling and force control in a constrained single-link arm [texte imprimé] / Bazaei, Ali, Auteur ; M. Moallem, Auteur . - 2012 . - 09 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 09 p.
Mots-clés : Force control Friction Hysteresis Manipulator dynamics Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : In this paper, we study friction characteristics of a constrained planar single-link arm in applications, where control of the end-point interaction force is required. The objective is to improve performance of a force control system by developing an adequate friction model. It is shown that hub friction increases with the applied force with the end-point force exhibiting significant hysteresis behavior. A friction model is presented for capturing these phenomena and compared with the widely used LuGre friction model. Effectiveness of the proposed model for friction compensation is further examined on an experimental force control system testbed. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Stochastic averaging for identification of feedback nonlinearities in thermoacoustic systems Type de document : texte imprimé Auteurs : Gregory Hagen, Auteur Année de publication : 2012 Article en page(s) : 10 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Gaussian processes Iterative methods Thermoacoustics Time series Vibrations Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : We present algorithms based on stochastic averaging for estimating nonlinear feedback parameters obtained from time series data with application to noise-driven nonlinear vibration systems, with particular emphasis on limit-cycling thermo-acoustic systems. The harmonic and Gaussian components of relevant signals are estimated from the probability density function (pdf) of an output signal from a single experiment. The respective feedback gains, along with a phase-shifting element are fit to a nominal (given) linear oscillator model from which the parameters of a nonlinearity are fit. When input-output data are available from multiple experiments, the feedback nonlinearity can be estimated point-wise via an iterative algorithm, applicable when the appropriate input signals have a constant (Gaussian) variance. The estimation procedures are demonstrated on a benchmark thermo-acoustic model and applied to time-series data obtained from a limit-cycling combustor rig experiment. In the latter case, relations between the feedback parameters and the fuel to air ratio are briefly discussed. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.[article] Stochastic averaging for identification of feedback nonlinearities in thermoacoustic systems [texte imprimé] / Gregory Hagen, Auteur . - 2012 . - 10 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.
Mots-clés : Gaussian processes Iterative methods Thermoacoustics Time series Vibrations Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : We present algorithms based on stochastic averaging for estimating nonlinear feedback parameters obtained from time series data with application to noise-driven nonlinear vibration systems, with particular emphasis on limit-cycling thermo-acoustic systems. The harmonic and Gaussian components of relevant signals are estimated from the probability density function (pdf) of an output signal from a single experiment. The respective feedback gains, along with a phase-shifting element are fit to a nominal (given) linear oscillator model from which the parameters of a nonlinearity are fit. When input-output data are available from multiple experiments, the feedback nonlinearity can be estimated point-wise via an iterative algorithm, applicable when the appropriate input signals have a constant (Gaussian) variance. The estimation procedures are demonstrated on a benchmark thermo-acoustic model and applied to time-series data obtained from a limit-cycling combustor rig experiment. In the latter case, relations between the feedback parameters and the fuel to air ratio are briefly discussed. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : Resonant frequencies in web process lines due to idle rollers and spans Type de document : texte imprimé Auteurs : P. R. Pagilla, Auteur ; Y. Diao, Auteur Année de publication : 2012 Article en page(s) : 10 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Rollers (machinery) Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : This paper presents the results of a study on the resonant frequencies of a system of idle rollers and web spans. A simple linear model that describes the behavior of tension in a web span is considered. It is shown experimentally on a web platform that the simple model is capable of predicting resonant frequencies in an idler system consisting of idle rollers and spans between two driven rollers. This model is used to investigate the behavior of the minimum resonant frequency as a function of the number of idle rollers and span lengths. Analytical solutions for computing the minimum resonant frequency for the one-idler system (one idle roller and two spans) and the two-idler system (two idle rollers and three spans) are given. Discussions on how to maximize the minimum resonant frequency for two-, three-, and four-idler systems based on numerical analysis are also given. An analytical approximation of the minimum resonant frequency for equal span lengths and any number of idle rollers is derived. This approximation is a lower bound on the minimum resonant frequency and tends to converge to it, with the increase in the number of idle rollers. This is useful in getting a quick and reliable estimate of the minimum resonant frequency in festoons/accumulators which contain many idle rollers and web spans of equal lengths. The results of this study are expected to be useful to the web machine designer and developers of web tension control systems. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.[article] Resonant frequencies in web process lines due to idle rollers and spans [texte imprimé] / P. R. Pagilla, Auteur ; Y. Diao, Auteur . - 2012 . - 10 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.
Mots-clés : Rollers (machinery) Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : This paper presents the results of a study on the resonant frequencies of a system of idle rollers and web spans. A simple linear model that describes the behavior of tension in a web span is considered. It is shown experimentally on a web platform that the simple model is capable of predicting resonant frequencies in an idler system consisting of idle rollers and spans between two driven rollers. This model is used to investigate the behavior of the minimum resonant frequency as a function of the number of idle rollers and span lengths. Analytical solutions for computing the minimum resonant frequency for the one-idler system (one idle roller and two spans) and the two-idler system (two idle rollers and three spans) are given. Discussions on how to maximize the minimum resonant frequency for two-, three-, and four-idler systems based on numerical analysis are also given. An analytical approximation of the minimum resonant frequency for equal span lengths and any number of idle rollers is derived. This approximation is a lower bound on the minimum resonant frequency and tends to converge to it, with the increase in the number of idle rollers. This is useful in getting a quick and reliable estimate of the minimum resonant frequency in festoons/accumulators which contain many idle rollers and web spans of equal lengths. The results of this study are expected to be useful to the web machine designer and developers of web tension control systems. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : A new approach to the control design of fuzzy dynamical systems Type de document : texte imprimé Auteurs : Chen, Ye-Hwa, Auteur Année de publication : 2012 Article en page(s) : 09 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Control system synthesis Fuzzy control set theory Robust Time-varying systems Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : A new approach to the control design for fuzzy dynamical systems is proposed. For a fuzzy dynamical system, the uncertainty lies within a fuzzy set. The desirable system performance is twofold: one deterministic and one fuzzy. While the deterministic performance assures the bottom line, the fuzzy performance enhances the cost consideration. Under this setting, a class of robust controls is proposed. The control is deterministic and is not if-then rules-based. An optimal design problem associated with the control is then formulated as a constrained optimization problem. We show that the problem can be solved and the solution exists and is unique. The closed-form solution and cost are explicitly shown. The resulting control is able to guarantee the prescribed deterministic performance and minimize the average fuzzy performance. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 09 p.[article] A new approach to the control design of fuzzy dynamical systems [texte imprimé] / Chen, Ye-Hwa, Auteur . - 2012 . - 09 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 09 p.
Mots-clés : Control system synthesis Fuzzy control set theory Robust Time-varying systems Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : A new approach to the control design for fuzzy dynamical systems is proposed. For a fuzzy dynamical system, the uncertainty lies within a fuzzy set. The desirable system performance is twofold: one deterministic and one fuzzy. While the deterministic performance assures the bottom line, the fuzzy performance enhances the cost consideration. Under this setting, a class of robust controls is proposed. The control is deterministic and is not if-then rules-based. An optimal design problem associated with the control is then formulated as a constrained optimization problem. We show that the problem can be solved and the solution exists and is unique. The closed-form solution and cost are explicitly shown. The resulting control is able to guarantee the prescribed deterministic performance and minimize the average fuzzy performance. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : A single differential equation for first-excursion time in a class of linear systems Type de document : texte imprimé Auteurs : Matthew B. Greytak, Auteur ; Franz S. Hover, Auteur Année de publication : 2012 Article en page(s) : 07 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Aircraft Closed loop systems Continuous Time Damping Differential equations Linear Marine vehicles Mobile robots Oscillators Path planning Structural engineering Time-varying Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : First-excursion times have been developed extensively in the literature for oscillators; one major application is structural dynamics of buildings. Using the fact that most closed-loop systems operate with a moderate to high damping ratio, we have derived a new procedure for calculating first-excursion times for a class of linear continuous, time-varying systems. In several examples, we show that the algorithm is both accurate and time-efficient. These are important attributes for real-time path planning in stochastic environments, and hence the work should be useful for autonomous robotic systems involving marine and air vehicles. DEWEY : 553 ISSN : 0022-0434
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 07 p.[article] A single differential equation for first-excursion time in a class of linear systems [texte imprimé] / Matthew B. Greytak, Auteur ; Franz S. Hover, Auteur . - 2012 . - 07 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 07 p.
Mots-clés : Aircraft Closed loop systems Continuous Time Damping Differential equations Linear Marine vehicles Mobile robots Oscillators Path planning Structural engineering Time-varying Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : First-excursion times have been developed extensively in the literature for oscillators; one major application is structural dynamics of buildings. Using the fact that most closed-loop systems operate with a moderate to high damping ratio, we have derived a new procedure for calculating first-excursion times for a class of linear continuous, time-varying systems. In several examples, we show that the algorithm is both accurate and time-efficient. These are important attributes for real-time path planning in stochastic environments, and hence the work should be useful for autonomous robotic systems involving marine and air vehicles. DEWEY : 553 ISSN : 0022-0434 Exemplaires
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Titre : Measurement of effective fluid bulk modulus in hydraulic system Type de document : texte imprimé Auteurs : Yang Huayong, Auteur ; Feng Bin, Auteur ; Gong Guofang, Auteur Année de publication : 2012 Article en page(s) : 06 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Elasticity Hydraulic fluids systems Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Effective fluid bulk modulus has significant influence on the stiffness and dynamic performance of hydraulic systems. It is always varied with different working parameters as air content, fluid pressure, and temperature. To estimating effective bulk modulus accurately is very important when designing high performance hydraulic systems. In this study, a measuring device was developed based on the definition of bulk modulus, and the measurement accuracy was estimated. Experiments were carried out using L-HM46 antiwear hydraulic fluid at approximately constant temperature, the results show that the good repeatability and pressure resolution can be achieved. Results also show that when pressure is low, the bulk modulus increases strongly as pressure increases; pressures over 8.5 MPa have slight influence on the bulk modulus. Effective fluid bulk modulus can be expressed as a function of working pressure when the air content is certain. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 06 p.[article] Measurement of effective fluid bulk modulus in hydraulic system [texte imprimé] / Yang Huayong, Auteur ; Feng Bin, Auteur ; Gong Guofang, Auteur . - 2012 . - 06 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 06 p.
Mots-clés : Elasticity Hydraulic fluids systems Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Effective fluid bulk modulus has significant influence on the stiffness and dynamic performance of hydraulic systems. It is always varied with different working parameters as air content, fluid pressure, and temperature. To estimating effective bulk modulus accurately is very important when designing high performance hydraulic systems. In this study, a measuring device was developed based on the definition of bulk modulus, and the measurement accuracy was estimated. Experiments were carried out using L-HM46 antiwear hydraulic fluid at approximately constant temperature, the results show that the good repeatability and pressure resolution can be achieved. Results also show that when pressure is low, the bulk modulus increases strongly as pressure increases; pressures over 8.5 MPa have slight influence on the bulk modulus. Effective fluid bulk modulus can be expressed as a function of working pressure when the air content is certain. DEWEY : 553 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000133000006 [...] Exemplaires
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Titre : A novel approach to evaluation of vibration source separation based on spatial distribution of sensors and Fourier transforms Type de document : texte imprimé Auteurs : Ali Mahvash, Auteur ; Aouni A. Lakis, Auteur Année de publication : 2012 Article en page(s) : 09 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Blind source separation Condition monitoring Fourier transforms Machinery Sensors Statistical analysis Vibrations Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : An obstacle in diagnosis of multicomponent machinery using multiple sensors to acquire vibration data is firstly found in the data acquisition itself. This is due to the fact that vibration signals collected by each sensor are a mixture of vibration produced by different components and noise; it is not evident what signals are produced by each component. A number of research studies have been carried out in which this problem was considered a blind source separation (BSS) problem and different mathematical methods were used to separate the signals. One complexity with applying such mathematical methods to separate vibration sources is that no metric or standard measure exists to evaluate the quality of the separation. In this study, a method based on statistical energy analysis (SEA) is proposed using Fourier transforms and the spatial distance between sensors and components. The principle of this method is based on the fact that each sensor, with respect to its location in the system, collects a different version of the vibration produced in the system. By applying a short time Fourier transform to the signals collected by multiple sensors and making use of a priori knowledge of the spatial distribution of sensor locations with respect to the components, the source of the peaks on the frequency spectra of the signals can be identified and attributed to the components. The performance of the method was verified using a series of experimental tests on synthetic signals and real laboratory signals collected from different bearings and the results confirmed the efficacy of the method. DEWEY : 553 ISSN : 0022-0434 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 09 p.[article] A novel approach to evaluation of vibration source separation based on spatial distribution of sensors and Fourier transforms [texte imprimé] / Ali Mahvash, Auteur ; Aouni A. Lakis, Auteur . - 2012 . - 09 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 09 p.
Mots-clés : Blind source separation Condition monitoring Fourier transforms Machinery Sensors Statistical analysis Vibrations Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : An obstacle in diagnosis of multicomponent machinery using multiple sensors to acquire vibration data is firstly found in the data acquisition itself. This is due to the fact that vibration signals collected by each sensor are a mixture of vibration produced by different components and noise; it is not evident what signals are produced by each component. A number of research studies have been carried out in which this problem was considered a blind source separation (BSS) problem and different mathematical methods were used to separate the signals. One complexity with applying such mathematical methods to separate vibration sources is that no metric or standard measure exists to evaluate the quality of the separation. In this study, a method based on statistical energy analysis (SEA) is proposed using Fourier transforms and the spatial distance between sensors and components. The principle of this method is based on the fact that each sensor, with respect to its location in the system, collects a different version of the vibration produced in the system. By applying a short time Fourier transform to the signals collected by multiple sensors and making use of a priori knowledge of the spatial distribution of sensor locations with respect to the components, the source of the peaks on the frequency spectra of the signals can be identified and attributed to the components. The performance of the method was verified using a series of experimental tests on synthetic signals and real laboratory signals collected from different bearings and the results confirmed the efficacy of the method. DEWEY : 553 ISSN : 0022-0434 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...] Exemplaires
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Titre : Semiglobal output feedback stabilization of a generalized class of MIMO nonlinear systems Type de document : texte imprimé Auteurs : Junyong Zhai, Auteur ; Chunjian Qian, Auteur ; Hui Ye, Auteur Année de publication : 2012 Article en page(s) : 05 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Asymptotic stability Closed loop systems Feedback Linear MIMO Nonlinear control Uncertain Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : This paper considers the problem of semiglobal stabilization by output feedback for a class of generalized multi-input and multi-output uncertain nonlinear systems. Due to the presence of mismatched uncertainties and the lack of triangularity condition, the systems under consideration are not uniformly completely observable. Combining the output feedback domination approach and block-backstepping scheme together, a series of linear output feedback controllers are constructed recursively for each subsystems and the closed-loop system is rendered semiglobally asymptotically stable. DEWEY : 553 ISSN : 0022-0434 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 05 p.[article] Semiglobal output feedback stabilization of a generalized class of MIMO nonlinear systems [texte imprimé] / Junyong Zhai, Auteur ; Chunjian Qian, Auteur ; Hui Ye, Auteur . - 2012 . - 05 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 05 p.
Mots-clés : Asymptotic stability Closed loop systems Feedback Linear MIMO Nonlinear control Uncertain Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : This paper considers the problem of semiglobal stabilization by output feedback for a class of generalized multi-input and multi-output uncertain nonlinear systems. Due to the presence of mismatched uncertainties and the lack of triangularity condition, the systems under consideration are not uniformly completely observable. Combining the output feedback domination approach and block-backstepping scheme together, a series of linear output feedback controllers are constructed recursively for each subsystems and the closed-loop system is rendered semiglobally asymptotically stable. DEWEY : 553 ISSN : 0022-0434 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...] Exemplaires
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Titre : Parameter identification for electrohydraulic valvetrain systems Type de document : texte imprimé Auteurs : James Gray, Auteur ; Krstic, Miroslav, Auteur ; Nalin Chaturvedi, Auteur Année de publication : 2012 Article en page(s) : 08 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Damping Hydraulic systems Least squares approximations Parameter estimation Pistons Valves Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : We consider an electrohydraulic valve system (EHVS) model with uncertain parameters that may possibly vary with time. This is a nonlinear third order system consisting of two clearly separated subsystems, one for the piston position and the other for the chamber pressure. The nonlinearities involved are flow-pressure characteristics of the solenoid valves, the pressure dynamics of the chamber due to varying volume, and a variable damping nonlinearity. We develop a parametric model that is linear in the unknown parameters of the system using filtering. We deal with a nonlinear parameterization in the variable damping term using the Taylor approximation. We design a parameter identifier, which employs a continuous-time unnormalized least-squares update law with a forgetting factor. This update law exponentially converges to the true parameters under a persistence of excitation condition, which is satisfied due to the periodic regime of operation of EHVS. We present simulation results that show good following of unknown parameters even with the presence of sensor noise. DEWEY : 553 ISSN : 0022-0434 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 08 p.[article] Parameter identification for electrohydraulic valvetrain systems [texte imprimé] / James Gray, Auteur ; Krstic, Miroslav, Auteur ; Nalin Chaturvedi, Auteur . - 2012 . - 08 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 08 p.
Mots-clés : Damping Hydraulic systems Least squares approximations Parameter estimation Pistons Valves Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : We consider an electrohydraulic valve system (EHVS) model with uncertain parameters that may possibly vary with time. This is a nonlinear third order system consisting of two clearly separated subsystems, one for the piston position and the other for the chamber pressure. The nonlinearities involved are flow-pressure characteristics of the solenoid valves, the pressure dynamics of the chamber due to varying volume, and a variable damping nonlinearity. We develop a parametric model that is linear in the unknown parameters of the system using filtering. We deal with a nonlinear parameterization in the variable damping term using the Taylor approximation. We design a parameter identifier, which employs a continuous-time unnormalized least-squares update law with a forgetting factor. This update law exponentially converges to the true parameters under a persistence of excitation condition, which is satisfied due to the periodic regime of operation of EHVS. We present simulation results that show good following of unknown parameters even with the presence of sensor noise. DEWEY : 553 ISSN : 0022-0434 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...] Exemplaires
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Titre : Fault-distribution dependent reliable control for T-S fuzzy time-delayed systems Type de document : texte imprimé Auteurs : Zhou Gu, Auteur ; Jinliang Liu, Auteur ; Chen Peng, Auteur Année de publication : 2012 Article en page(s) : 04 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Actuators Delays Fuzzy control systems Linear matrix inequalities Lyapunov methods Reliability Statistical distributions Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : The problem of reliable control for T-S fuzzy time-delayed systems is investigated in this paper. A more practical and general actuator-fault-model is proposed by assuming that actuators fault obeys a certain probabilistic distribution. In order to get less conservative results, the state-delay is segmentalized into several continuous equivalent subintervals in constructing the Lyapunov function and stochastic fault information is also introduced in deriving the results. Sufficient conditions for the existence of reliable controller are expressed by a set of linear matrix inequalities. Illustrative examples are exploited to show the effectiveness of the proposed design procedures. DEWEY : 553 ISSN : 0022-0434 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 04 p.[article] Fault-distribution dependent reliable control for T-S fuzzy time-delayed systems [texte imprimé] / Zhou Gu, Auteur ; Jinliang Liu, Auteur ; Chen Peng, Auteur . - 2012 . - 04 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 04 p.
Mots-clés : Actuators Delays Fuzzy control systems Linear matrix inequalities Lyapunov methods Reliability Statistical distributions Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : The problem of reliable control for T-S fuzzy time-delayed systems is investigated in this paper. A more practical and general actuator-fault-model is proposed by assuming that actuators fault obeys a certain probabilistic distribution. In order to get less conservative results, the state-delay is segmentalized into several continuous equivalent subintervals in constructing the Lyapunov function and stochastic fault information is also introduced in deriving the results. Sufficient conditions for the existence of reliable controller are expressed by a set of linear matrix inequalities. Illustrative examples are exploited to show the effectiveness of the proposed design procedures. DEWEY : 553 ISSN : 0022-0434 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...] Exemplaires
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Titre : Partial stabilization approach to 3-dimensional guidance law design Type de document : texte imprimé Auteurs : T. Binazadeh, Auteur ; Yazdanpanah, M. J., Auteur Année de publication : 2012 Article en page(s) : 04 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Missile guidance Robust control Variable structure systems Vehicle dynamics Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : In this paper, a new approach to design the 3-dimensional missile guidance law, based on partial stabilization, is presented. The approach is based on the classification of the state variables within the guidance system dynamics with respect to their required stabilization properties. The resulting guidance law enables the missile to intercept highly maneuvering targets within a finite interception time. Effectiveness of the proposed guidance law is demonstrated through analysis and simulations. DEWEY : 553 ISSN : 0022-0434 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 04 p.[article] Partial stabilization approach to 3-dimensional guidance law design [texte imprimé] / T. Binazadeh, Auteur ; Yazdanpanah, M. J., Auteur . - 2012 . - 04 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 04 p.
Mots-clés : Missile guidance Robust control Variable structure systems Vehicle dynamics Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : In this paper, a new approach to design the 3-dimensional missile guidance law, based on partial stabilization, is presented. The approach is based on the classification of the state variables within the guidance system dynamics with respect to their required stabilization properties. The resulting guidance law enables the missile to intercept highly maneuvering targets within a finite interception time. Effectiveness of the proposed guidance law is demonstrated through analysis and simulations. DEWEY : 553 ISSN : 0022-0434 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...] Exemplaires
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Titre : Load and stress analysis for the swash plate of an axial piston pump/motor Type de document : texte imprimé Auteurs : M. Z. Norhirni, Auteur ; Hamdi, M., Auteur ; S. Nurmaya Musa, Auteur Année de publication : 2012 Article en page(s) : 10 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Braking Force control Hybrid electric vehicles Hydraulic systems Pistons Plates (structures) Pumps Shear modulus Stress analysis Torque Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : In an axial piston pump design, the swash plate plays an important role in controlling the displacement of the pump, especially in a closed loop system. In this paper, the axial piston pump is incorporated into the design of a hydraulic regenerative braking system for hybrid vehicles. The pump in this configuration should function in dual mode, as a pump and as a motor. For this to occur, the swash plate should swing in two opposite directions. The swash plate presented in this paper is designed for stability and ease of control. Analytical analysis of torque and forces were conducted using MATLAB software to verify the motion of the swash plate. Furthermore, finite element analysis was also carried out to evaluate the rigidity and stress in the system. The analytical evaluation has shown that as the swash plate angle increases, the required control force and torque increase almost linearly. However, the change of the plate angle was found to have no effect on the force exerted on the X-axis and the torque exerted on the Z-axis. DEWEY : 553 ISSN : 0022-0434 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.[article] Load and stress analysis for the swash plate of an axial piston pump/motor [texte imprimé] / M. Z. Norhirni, Auteur ; Hamdi, M., Auteur ; S. Nurmaya Musa, Auteur . - 2012 . - 10 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 10 p.
Mots-clés : Braking Force control Hybrid electric vehicles Hydraulic systems Pistons Plates (structures) Pumps Shear modulus Stress analysis Torque Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : In an axial piston pump design, the swash plate plays an important role in controlling the displacement of the pump, especially in a closed loop system. In this paper, the axial piston pump is incorporated into the design of a hydraulic regenerative braking system for hybrid vehicles. The pump in this configuration should function in dual mode, as a pump and as a motor. For this to occur, the swash plate should swing in two opposite directions. The swash plate presented in this paper is designed for stability and ease of control. Analytical analysis of torque and forces were conducted using MATLAB software to verify the motion of the swash plate. Furthermore, finite element analysis was also carried out to evaluate the rigidity and stress in the system. The analytical evaluation has shown that as the swash plate angle increases, the required control force and torque increase almost linearly. However, the change of the plate angle was found to have no effect on the force exerted on the X-axis and the torque exerted on the Z-axis. DEWEY : 553 ISSN : 0022-0434 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...] Exemplaires
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Titre : Adaptive position control of an electrohydraulic servo system with load disturbance rejection and friction compensation Type de document : texte imprimé Auteurs : Honorine Angue-Mintsa, Auteur ; Ravinder Venugopal, Auteur ; Jean-Pierre Kenné, Auteur Année de publication : 2012 Article en page(s) : 08 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Adaptive control Electrohydraulic equipment Feedback Friction Lyapunov methods Position Robust Servomechanisms Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Electrohydraulic servo systems (EHSS) are used for several engineering applications, and in particular, for efficient handling of heavy loads. These systems are characterized by pronounced nonlinearities and are also subject to parameter variations during operation, friction effects, and variable loads. Several studies have addressed the nonlinear nature of EHSS; however, only a few control schemes explicitly address friction and load disturbance effects along with parameter variations. Fuzzy and/or sliding mode versions of feedback linearizing controllers have been used to compensate for the external loads disturbances in the control of EHSS. However, real-time implementations issues limit the use of these techniques. While adaptive control using a feedback-linearization based controller structure has been shown to be effective in the presence of parameter variations, load and friction effects are typically not considered. In this paper, we present a nonlinear adaptive feedback linearizing position controller for an EHSS, which is robust to parameter uncertainty while achieving load disturbances rejection/attenuation and friction compensation. The adaptation law is derived using a Lyapunov approach. Simulation results using the proposed controller are compared to those using a nonadaptive feedback linearizing controller as well as a proportional-integral-derivative (PID) controller, in the presence of torque load disturbance, friction, and uncertainty in the hydraulic parameters. These results show improved tracking performance with the proposed controller. To address implementation concerns, simulation results with noise effects and valve saturation are also presented. DEWEY : 553 ISSN : 0022-0434 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...]
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 08 p.[article] Adaptive position control of an electrohydraulic servo system with load disturbance rejection and friction compensation [texte imprimé] / Honorine Angue-Mintsa, Auteur ; Ravinder Venugopal, Auteur ; Jean-Pierre Kenné, Auteur . - 2012 . - 08 p.
Dynamic systems
Langues : Anglais (eng)
in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 6 (Novembre 2011) . - 08 p.
Mots-clés : Adaptive control Electrohydraulic equipment Feedback Friction Lyapunov methods Position Robust Servomechanisms Index. décimale : 553 Géologie économique. Minérographie. Minéraux. Formation et gisements de minerais Résumé : Electrohydraulic servo systems (EHSS) are used for several engineering applications, and in particular, for efficient handling of heavy loads. These systems are characterized by pronounced nonlinearities and are also subject to parameter variations during operation, friction effects, and variable loads. Several studies have addressed the nonlinear nature of EHSS; however, only a few control schemes explicitly address friction and load disturbance effects along with parameter variations. Fuzzy and/or sliding mode versions of feedback linearizing controllers have been used to compensate for the external loads disturbances in the control of EHSS. However, real-time implementations issues limit the use of these techniques. While adaptive control using a feedback-linearization based controller structure has been shown to be effective in the presence of parameter variations, load and friction effects are typically not considered. In this paper, we present a nonlinear adaptive feedback linearizing position controller for an EHSS, which is robust to parameter uncertainty while achieving load disturbances rejection/attenuation and friction compensation. The adaptation law is derived using a Lyapunov approach. Simulation results using the proposed controller are compared to those using a nonadaptive feedback linearizing controller as well as a proportional-integral-derivative (PID) controller, in the presence of torque load disturbance, friction, and uncertainty in the hydraulic parameters. These results show improved tracking performance with the proposed controller. To address implementation concerns, simulation results with noise effects and valve saturation are also presented. DEWEY : 553 ISSN : 0022-0434 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...] Exemplaires
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