Dépouillements

Experimental testing and analysis of inerter devices / Christos Papageorgiou in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 11 p. Titre : Experimental testing and analysis of inerter devices Type de document : texte imprimé Auteurs : Christos Papageorgiou, Auteur ; Neil E. Houghton, Auteur ; Malcolm C. Smith, Auteur Année de publication : 2009 Article en page(s) : 11 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : mechanical  devices;  stand-alone  inerter  devices Résumé : This paper presents a first in-depth experimental study of mechanical devices that are designed to approximate the dynamics of the ideal inerter, which is a two-terminal mechanical element analogous to the ungrounded capacitor. The focus of the paper is experimental testing and identification of stand-alone inerter devices as well as the study of practical issues involved in their feedback control using standard hydraulic damper test rigs. Two contrasting inerter embodiments are studied, one in which a flywheel is driven by a rack-and-pinion mechanism and the other employing a ballscrew. Due to the fact that the ideal inerter is a dynamic element whose admittance function is 90 deg out of phase with that of the ideal damper, particular attention is needed to ensure closed-loop stability in testing using standard hydraulic damper test rigs. As expected, instability is observed in default configurations, and it is seen to manifest itself in a nonlinear manner with backlash playing a significant role. By using a basic model of the hydraulic rig and a model of an ideal inerter with backlash, the nature of the instability is reproduced and explained in a qualitative way. To achieve closed-loop stability without the need to redesign the controller as a function of the load, a methodology is proposed involving the design of a mechanical buffer network to be connected in series with the inerter device. It is demonstrated that this approach removes the instability problem for a wide range of inertance loads. Finally, the dynamic characteristics of the inerter devices are identified. It is verified experimentally that the admittance of the devices approaches the ideal inerter admittance over a useful frequency range and that friction in the devices is a major source of deviation from the ideal inerter behavior. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...] [article] Experimental testing and analysis of inerter devices [texte imprimé] / Christos Papageorgiou, Auteur ; Neil E. Houghton, Auteur ; Malcolm C. Smith, Auteur . - 2009 . - 11 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 11 p. Mots-clés : mechanical  devices;  stand-alone  inerter  devices Résumé : This paper presents a first in-depth experimental study of mechanical devices that are designed to approximate the dynamics of the ideal inerter, which is a two-terminal mechanical element analogous to the ungrounded capacitor. The focus of the paper is experimental testing and identification of stand-alone inerter devices as well as the study of practical issues involved in their feedback control using standard hydraulic damper test rigs. Two contrasting inerter embodiments are studied, one in which a flywheel is driven by a rack-and-pinion mechanism and the other employing a ballscrew. Due to the fact that the ideal inerter is a dynamic element whose admittance function is 90 deg out of phase with that of the ideal damper, particular attention is needed to ensure closed-loop stability in testing using standard hydraulic damper test rigs. As expected, instability is observed in default configurations, and it is seen to manifest itself in a nonlinear manner with backlash playing a significant role. By using a basic model of the hydraulic rig and a model of an ideal inerter with backlash, the nature of the instability is reproduced and explained in a qualitative way. To achieve closed-loop stability without the need to redesign the controller as a function of the load, a methodology is proposed involving the design of a mechanical buffer network to be connected in series with the inerter device. It is demonstrated that this approach removes the instability problem for a wide range of inertance loads. Finally, the dynamic characteristics of the inerter devices are identified. It is verified experimentally that the admittance of the devices approaches the ideal inerter admittance over a useful frequency range and that friction in the devices is a major source of deviation from the ideal inerter behavior. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...]

Mean value modeling and analysis of HCCI diesel engines with external mixture formation / Canova, Marcello in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 14 p. Titre : Mean value modeling and analysis of HCCI diesel engines with external mixture formation Type de document : texte imprimé Auteurs : Canova, Marcello, Auteur ; Midlam-Mohler, Shawn, Auteur ; Yann Guezennec, Auteur Année de publication : 2009 Article en page(s) : 14 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : pressure;  flow  (dynamics);  temperature;  combustion;  fuels;  engines;  stress;  cylinders;  diesel  engines;  exhaust  systems;  mixtures;  exhaust  gas  recirculation;  homogeneous  charge  compression  ignition  engines Résumé : Homogeneous charge compression ignition (HCCI) is a promising concept for internal combustion engines that can considerably decrease NOx and soot emissions in part-load operations without penalizing fuel consumption. The HCCI combustion can be implemented in direct injection diesel engines without major modifications by introducing a specialized fuel injector in the intake port. This decouples the homogeneous mixture formation from the traditional in-cylinder injection, thus providing two fueling systems that can be used to optimize exhaust emissions and fuel consumption over the engine operating range. However, understanding and controlling the complex mechanisms and interactions driving the HCCI combustion process is still a difficult task. For this reason, it is essential to identify the most important control parameters and understand their influence on the auto-ignition process. The current work analyzes HCCI combustion with external mixture formation through experimental investigation and the definition of a control-oriented model. An extensive testing activity was performed on a passenger car diesel engine equipped with an external fuel atomizer to operate in HCCI mode. This provided an understanding of the process as well as experimental data to identify a mean value model of the system and its parameters. The model includes a thermodynamic combustion calculation that estimates the heat release, cylinder pressure, and the relevant variables for combustion control. The tool developed was then validated and used for analyzing the system behavior in steady state conditions. Finally, a description of the HCCI system behavior in transient operations is presented. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...] [article] Mean value modeling and analysis of HCCI diesel engines with external mixture formation [texte imprimé] / Canova, Marcello, Auteur ; Midlam-Mohler, Shawn, Auteur ; Yann Guezennec, Auteur . - 2009 . - 14 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 14 p. Mots-clés : pressure;  flow  (dynamics);  temperature;  combustion;  fuels;  engines;  stress;  cylinders;  diesel  engines;  exhaust  systems;  mixtures;  exhaust  gas  recirculation;  homogeneous  charge  compression  ignition  engines Résumé : Homogeneous charge compression ignition (HCCI) is a promising concept for internal combustion engines that can considerably decrease NOx and soot emissions in part-load operations without penalizing fuel consumption. The HCCI combustion can be implemented in direct injection diesel engines without major modifications by introducing a specialized fuel injector in the intake port. This decouples the homogeneous mixture formation from the traditional in-cylinder injection, thus providing two fueling systems that can be used to optimize exhaust emissions and fuel consumption over the engine operating range. However, understanding and controlling the complex mechanisms and interactions driving the HCCI combustion process is still a difficult task. For this reason, it is essential to identify the most important control parameters and understand their influence on the auto-ignition process. The current work analyzes HCCI combustion with external mixture formation through experimental investigation and the definition of a control-oriented model. An extensive testing activity was performed on a passenger car diesel engine equipped with an external fuel atomizer to operate in HCCI mode. This provided an understanding of the process as well as experimental data to identify a mean value model of the system and its parameters. The model includes a thermodynamic combustion calculation that estimates the heat release, cylinder pressure, and the relevant variables for combustion control. The tool developed was then validated and used for analyzing the system behavior in steady state conditions. Finally, a description of the HCCI system behavior in transient operations is presented. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...]

Feedback linearization based generalized predictive control of jupiter icy moons orbiter / Jianjun, Shi in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 10 p. Titre : Feedback linearization based generalized predictive control of jupiter icy moons orbiter Type de document : texte imprimé Auteurs : Jianjun, Shi, Auteur ; Kelkar, Atul G., Auteur Année de publication : 2009 Article en page(s) : 10 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : control  equipment;  equations  of  motion;  design;  equations;  feedback;  predictive  control;  space  vehicles Résumé : This paper presents a nonlinear dynamic model of Jupiter Icy Moons Orbiter (JIMO), a concept design of a spacecraft intended to orbit the three icy moons of Jupiter, namely, Europa, Ganymede, and Callisto. The work in this paper represents a part of the feasibility study conducted to assess control requirements for the JIMO mission. A nonlinear dynamic model of JIMO is derived, which includes rigid body as well as flexible body dynamics. This paper presents a novel hybrid control strategy, which combines feedback linearization with generalized predictive control methodology in a two-step approach for attitude control of the spacecraft. This feedback linearization based generalized predictive control (FLGPC) law is used to accomplish a representative realistic in-orbit maneuver to test the efficacy of the controller. The controller performance shows that the FLGPC is a viable methodology for attitude control of a similar class of spacecraft. The results presented are a part of exhaustive study conducted to evaluate various controller designs. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...] [article] Feedback linearization based generalized predictive control of jupiter icy moons orbiter [texte imprimé] / Jianjun, Shi, Auteur ; Kelkar, Atul G., Auteur . - 2009 . - 10 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 10 p. Mots-clés : control  equipment;  equations  of  motion;  design;  equations;  feedback;  predictive  control;  space  vehicles Résumé : This paper presents a nonlinear dynamic model of Jupiter Icy Moons Orbiter (JIMO), a concept design of a spacecraft intended to orbit the three icy moons of Jupiter, namely, Europa, Ganymede, and Callisto. The work in this paper represents a part of the feasibility study conducted to assess control requirements for the JIMO mission. A nonlinear dynamic model of JIMO is derived, which includes rigid body as well as flexible body dynamics. This paper presents a novel hybrid control strategy, which combines feedback linearization with generalized predictive control methodology in a two-step approach for attitude control of the spacecraft. This feedback linearization based generalized predictive control (FLGPC) law is used to accomplish a representative realistic in-orbit maneuver to test the efficacy of the controller. The controller performance shows that the FLGPC is a viable methodology for attitude control of a similar class of spacecraft. The results presented are a part of exhaustive study conducted to evaluate various controller designs. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...]

Wireless swimming microrobot: design, analysis, and experiments / Yongshun Zhang in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 08 p. Titre : Wireless swimming microrobot: design, analysis, and experiments Type de document : texte imprimé Auteurs : Yongshun Zhang, Auteur ; Guangjun Liu, Auteur Année de publication : 2009 Article en page(s) : 08 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : resonance;  force;  motion;  robots;  magnetic  fields;  propulsion;  engineering  prototypes;  actuators;  design;  vibration;  fins;  frequency;  shapes;  dynamic  models Résumé : This paper presents a bidirectional wireless swimming microrobot that has been developed, analyzed, and experimentally tested. The robot is developed based on fin beating propulsion, using giant magnetostrictive films for head and tail fins. An innovative drive approach, using separate second order resonance frequencies of the head and tail fins to generate forward and backward thrusts, is proposed and implemented on a bidirectional swimming microrobot prototype. Dynamic model of the proposed microrobot has been derived based on theoretical analysis. Simulation and experimental results have demonstrated the feasibility of the proposed drive approach and design. The developed swimming microrobot features a low driving frequency, low power consumption, and a large range of swimming speed in both the forward and backward directions. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...] [article] Wireless swimming microrobot: design, analysis, and experiments [texte imprimé] / Yongshun Zhang, Auteur ; Guangjun Liu, Auteur . - 2009 . - 08 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 08 p. Mots-clés : resonance;  force;  motion;  robots;  magnetic  fields;  propulsion;  engineering  prototypes;  actuators;  design;  vibration;  fins;  frequency;  shapes;  dynamic  models Résumé : This paper presents a bidirectional wireless swimming microrobot that has been developed, analyzed, and experimentally tested. The robot is developed based on fin beating propulsion, using giant magnetostrictive films for head and tail fins. An innovative drive approach, using separate second order resonance frequencies of the head and tail fins to generate forward and backward thrusts, is proposed and implemented on a bidirectional swimming microrobot prototype. Dynamic model of the proposed microrobot has been derived based on theoretical analysis. Simulation and experimental results have demonstrated the feasibility of the proposed drive approach and design. The developed swimming microrobot features a low driving frequency, low power consumption, and a large range of swimming speed in both the forward and backward directions. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...]

Identification of time-varying time constants of thermocouple sensors and its application to temperature measurement / Kenneth Kar in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) Titre : Identification of time-varying time constants of thermocouple sensors and its application to temperature measurement Type de document : texte imprimé Auteurs : Kenneth Kar, Auteur ; Akshya K. Swain, Auteur ; Robert Raine, Auteur Année de publication : 2009 Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : temperature;  sensors;  temperature  measurement;  algorithms;  errors;  thermocouples Résumé : The present study addresses the problem of estimating time-varying time constants associated with thermocouple sensors by a set of basis functions. By expanding each time-varying time constant onto a finite set of basis sequences, the time-varying identification problem reduces to a parameter estimation problem of a time-invariant system. The proposed algorithm, to be called as orthogonal least-squares with basis function expansion algorithm, combines the orthogonal least-squares algorithm with an error reduction ratio test to include significant basis functions into the model, which results in a parsimonious model structure. The performance of the method was compared with a linear Kalman filter. Simulations on engine data have demonstrated that the proposed method performs satisfactorily and is better than the Kalman filter. The new technique has been applied in a Stirling cycle compressor. The sinusoidal variations in time constant are tracked properly using the new technique, but the linear Kalman filter fails to do so. Both model validation and thermodynamic laws confirm that the new technique gives unbiased estimates and that the assumed thermocouple model is adequate. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...] [article] Identification of time-varying time constants of thermocouple sensors and its application to temperature measurement [texte imprimé] / Kenneth Kar, Auteur ; Akshya K. Swain, Auteur ; Robert Raine, Auteur . - 2009. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) Mots-clés : temperature;  sensors;  temperature  measurement;  algorithms;  errors;  thermocouples Résumé : The present study addresses the problem of estimating time-varying time constants associated with thermocouple sensors by a set of basis functions. By expanding each time-varying time constant onto a finite set of basis sequences, the time-varying identification problem reduces to a parameter estimation problem of a time-invariant system. The proposed algorithm, to be called as orthogonal least-squares with basis function expansion algorithm, combines the orthogonal least-squares algorithm with an error reduction ratio test to include significant basis functions into the model, which results in a parsimonious model structure. The performance of the method was compared with a linear Kalman filter. Simulations on engine data have demonstrated that the proposed method performs satisfactorily and is better than the Kalman filter. The new technique has been applied in a Stirling cycle compressor. The sinusoidal variations in time constant are tracked properly using the new technique, but the linear Kalman filter fails to do so. Both model validation and thermodynamic laws confirm that the new technique gives unbiased estimates and that the assumed thermocouple model is adequate. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...]

Design and development of a novel 2DOF actuation slosh rig / Prasanna S. Gandhi in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 09 p. Titre : Design and development of a novel 2DOF actuation slosh rig Type de document : texte imprimé Auteurs : Prasanna S. Gandhi, Auteur ; Keyur B. Joshi, Auteur ; N. Ananthkrishnan, Auteur Année de publication : 2009 Article en page(s) : 09 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : slosh  dynamics;  mechatronic  design;  excitations Résumé : Sloshing of liquid in a tank is critical in several areas, including launch vehicles carrying liquid fuel, satellites, industrial packaging of liquids, systems handling molten metal, and so on. Hence modeling, characterization, and control of nonlinear slosh phenomena are important in these applications. To study slosh dynamics, develop useful identification schemes, and design and verify slosh control algorithms, a new 2DOF actuation slosh rig is reported in this paper considering the fact that most of the times these tanks are subjected to linear as well as pitching excitation/control inputs. The paper discusses mechatronic design and several advantages that the new design offers. A slosh phenomenon of beating observed when both lateral and pitching excitations are provided is simulated using a model based on pendulum approximation to slosh and is further verified in experiments. The results confirm that the effects of both excitations together can be detrimental against separate excitations of the same amplitude. Moreover, slosh compensation in open loop is demonstrated by giving excitation in pitching and developing a compensatory input in the lateral direction. Furthermore, active slosh control strategy is developed and its effectiveness is demonstrated with control in translation and disturbance in pitching. Thus the proposed rig is an ideal tool for the study, identification, and control development of slosh in the presence of two excitations/inputs. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...] [article] Design and development of a novel 2DOF actuation slosh rig [texte imprimé] / Prasanna S. Gandhi, Auteur ; Keyur B. Joshi, Auteur ; N. Ananthkrishnan, Auteur . - 2009 . - 09 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 09 p. Mots-clés : slosh  dynamics;  mechatronic  design;  excitations Résumé : Sloshing of liquid in a tank is critical in several areas, including launch vehicles carrying liquid fuel, satellites, industrial packaging of liquids, systems handling molten metal, and so on. Hence modeling, characterization, and control of nonlinear slosh phenomena are important in these applications. To study slosh dynamics, develop useful identification schemes, and design and verify slosh control algorithms, a new 2DOF actuation slosh rig is reported in this paper considering the fact that most of the times these tanks are subjected to linear as well as pitching excitation/control inputs. The paper discusses mechatronic design and several advantages that the new design offers. A slosh phenomenon of beating observed when both lateral and pitching excitations are provided is simulated using a model based on pendulum approximation to slosh and is further verified in experiments. The results confirm that the effects of both excitations together can be detrimental against separate excitations of the same amplitude. Moreover, slosh compensation in open loop is demonstrated by giving excitation in pitching and developing a compensatory input in the lateral direction. Furthermore, active slosh control strategy is developed and its effectiveness is demonstrated with control in translation and disturbance in pitching. Thus the proposed rig is an ideal tool for the study, identification, and control development of slosh in the presence of two excitations/inputs. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...]

Indicated mean effective pressure estimator order determination and reduction when using estimated engine statistics / J. S. Arbuckle in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 10 p. Titre : Indicated mean effective pressure estimator order determination and reduction when using estimated engine statistics Type de document : texte imprimé Auteurs : J. S. Arbuckle, Auteur ; J. B. Burl, Auteur Année de publication : 2009 Article en page(s) : 10 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : pressure;  engines;  errors Résumé : The indicated mean effective pressure (IMEP) is typically used as an engine running quality metric. IMEP depends on cylinder pressure, which is costly to measure, therefore it is useful to estimate IMEP from currently measured crankshaft encoder data. In this paper, the difficulties in developing an optimal linear estimator from acceleration computed from crankshaft rotational speed and cylinder pressure data are discussed, and strategies are presented to reduce these difficulties. Estimating IMEP from crankshaft data requires the determination of which data to use in the estimator. Without this step, the estimator can become unnecessarily complex due the inclusion of strongly correlated data points in the estimator. A strategy to determine the angular location of the acceleration points to use is presented and is shown to greatly reduce the estimator complexity without significantly affecting estimation error. Additionally, while increasing the estimator order usually decreases the estimation error, it will be shown that increasing the estimator order can actually increase the estimation error. This effect is due to uncertainties in the gains of the estimator. These uncertainties in the gains can result from using limited training data to estimate the statistics necessary to compute the gains or when dealing with a nonstationary system. A method of reducing the effect of these uncertainties by optimizing the estimator order based on the number of available training data cycles is developed and demonstrated. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...] [article] Indicated mean effective pressure estimator order determination and reduction when using estimated engine statistics [texte imprimé] / J. S. Arbuckle, Auteur ; J. B. Burl, Auteur . - 2009 . - 10 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 10 p. Mots-clés : pressure;  engines;  errors Résumé : The indicated mean effective pressure (IMEP) is typically used as an engine running quality metric. IMEP depends on cylinder pressure, which is costly to measure, therefore it is useful to estimate IMEP from currently measured crankshaft encoder data. In this paper, the difficulties in developing an optimal linear estimator from acceleration computed from crankshaft rotational speed and cylinder pressure data are discussed, and strategies are presented to reduce these difficulties. Estimating IMEP from crankshaft data requires the determination of which data to use in the estimator. Without this step, the estimator can become unnecessarily complex due the inclusion of strongly correlated data points in the estimator. A strategy to determine the angular location of the acceleration points to use is presented and is shown to greatly reduce the estimator complexity without significantly affecting estimation error. Additionally, while increasing the estimator order usually decreases the estimation error, it will be shown that increasing the estimator order can actually increase the estimation error. This effect is due to uncertainties in the gains of the estimator. These uncertainties in the gains can result from using limited training data to estimate the statistics necessary to compute the gains or when dealing with a nonstationary system. A method of reducing the effect of these uncertainties by optimizing the estimator order based on the number of available training data cycles is developed and demonstrated. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...]

Robust and simplified design of slip control system for torque converter lock-up clutch / R. Hibino in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 10 p. Titre : Robust and simplified design of slip control system for torque converter lock-up clutch Type de document : texte imprimé Auteurs : R. Hibino, Auteur ; M. Osawa, Auteur ; K. Kono, Auteur Année de publication : 2009 Article en page(s) : 10 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : stability;  locks  (waterways);  control  systems;  control  equipment;  torque  converters;  design;  modeling;  vehicles;  errors;  fittings Résumé : A torque converter lock-up clutch slip control system, which is designed to improve fuel economy, must be able to precisely regulate slip speed. Also the system must have a high level of robustness for coping with changes in the operating conditions and any deterioration in the automatic transmission fluid and the clutch. Moreover, to reduce the design time, the design process must be as simple as possible. In this paper, we first propose a loop shaping that aims to optimize complementary sensitivity function of the control system, while satisfying the abovementioned requirements of performance and robustness. Next, a method for simplifying the design process is proposed, that is, a model and a controller are expressed by interpolation. A controller set, which has a relationship of duality to the interpolation parameters of the model, is created in advance so that the construction of a new control system can be realized by identifying the characteristic parameters only. From application to the actual design process for a vehicle, we verified that the design time was reduced to less than 1∕3 of that required for the conventional method. This new method has already been adopted for the design and fitting of new products. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...] [article] Robust and simplified design of slip control system for torque converter lock-up clutch [texte imprimé] / R. Hibino, Auteur ; M. Osawa, Auteur ; K. Kono, Auteur . - 2009 . - 10 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 10 p. Mots-clés : stability;  locks  (waterways);  control  systems;  control  equipment;  torque  converters;  design;  modeling;  vehicles;  errors;  fittings Résumé : A torque converter lock-up clutch slip control system, which is designed to improve fuel economy, must be able to precisely regulate slip speed. Also the system must have a high level of robustness for coping with changes in the operating conditions and any deterioration in the automatic transmission fluid and the clutch. Moreover, to reduce the design time, the design process must be as simple as possible. In this paper, we first propose a loop shaping that aims to optimize complementary sensitivity function of the control system, while satisfying the abovementioned requirements of performance and robustness. Next, a method for simplifying the design process is proposed, that is, a model and a controller are expressed by interpolation. A controller set, which has a relationship of duality to the interpolation parameters of the model, is created in advance so that the construction of a new control system can be realized by identifying the characteristic parameters only. From application to the actual design process for a vehicle, we verified that the design time was reduced to less than 1∕3 of that required for the conventional method. This new method has already been adopted for the design and fitting of new products. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...]

Trajectory optimization for DDE models of supercavitating underwater vehicles / Carlo L. Bottasso in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 18 p. Titre : Trajectory optimization for DDE models of supercavitating underwater vehicles Type de document : texte imprimé Auteurs : Carlo L. Bottasso, Auteur ; Francesco Scorcelletti, Auteur ; Massimo Ruzzene, Auteur Année de publication : 2009 Article en page(s) : 18 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : force;  trajectories  (physics);  optimization;  vehicles;  cavities;  delays;  flight Résumé : In this study we first develop a flight mechanics model for supercavitating vehicles, which is formulated to account for the dependence of the cavity shape from the past history of the system. This mathematical model is governed by a particular class of delay differential equations, featuring time delays on the states of the system. Next, flight trajectories and maneuvering strategies for supercavitating vehicles are obtained by solving an optimal control problem, whose solution, given a cost function and general constraints and bounds on states and controls, yields the control time histories that maneuver the vehicle according to a desired strategy, together with the associated flight path. The optimal control problem is solved using a novel direct multiple shooting approach, which is formulated to properly handle conditions dictated by the delay differential equation formulation governing the dynamic behavior of the vehicle. Specifically, the new formulation enforces the state continuity line conditions in a least-squares sense using local interpolations, which supports local time stepping and drastically reduces the number of optimization unknowns. Examples of maneuvers and resulting trajectories demonstrate the effectiveness of the proposed methodology and the generality of the formulation. The results are also compared with those obtained from a previously developed model governed by ordinary differential equations to highlight the differences and demonstrate the need for the current formulation. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...] [article] Trajectory optimization for DDE models of supercavitating underwater vehicles [texte imprimé] / Carlo L. Bottasso, Auteur ; Francesco Scorcelletti, Auteur ; Massimo Ruzzene, Auteur . - 2009 . - 18 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 18 p. Mots-clés : force;  trajectories  (physics);  optimization;  vehicles;  cavities;  delays;  flight Résumé : In this study we first develop a flight mechanics model for supercavitating vehicles, which is formulated to account for the dependence of the cavity shape from the past history of the system. This mathematical model is governed by a particular class of delay differential equations, featuring time delays on the states of the system. Next, flight trajectories and maneuvering strategies for supercavitating vehicles are obtained by solving an optimal control problem, whose solution, given a cost function and general constraints and bounds on states and controls, yields the control time histories that maneuver the vehicle according to a desired strategy, together with the associated flight path. The optimal control problem is solved using a novel direct multiple shooting approach, which is formulated to properly handle conditions dictated by the delay differential equation formulation governing the dynamic behavior of the vehicle. Specifically, the new formulation enforces the state continuity line conditions in a least-squares sense using local interpolations, which supports local time stepping and drastically reduces the number of optimization unknowns. Examples of maneuvers and resulting trajectories demonstrate the effectiveness of the proposed methodology and the generality of the formulation. The results are also compared with those obtained from a previously developed model governed by ordinary differential equations to highlight the differences and demonstrate the need for the current formulation. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...]

Sliding mode control of mechanical systems actuated by shape memory alloy / Hashem Ashrafiuon in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 06 p. Titre : Sliding mode control of mechanical systems actuated by shape memory alloy Type de document : texte imprimé Auteurs : Hashem Ashrafiuon, Auteur ; Vijay Reddy Jala, Auteur Année de publication : 2009 Article en page(s) : 06 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : temperature;  phase  transitions;  cooling;  control  equipment;  robots;  wire;  shape  memory  alloys;  stress;  equations  of  motion;  sliding  mode  control;  actuators;  convection;  modeling;  equations;  Kalman  filters;  position  control;  heating Résumé : This paper presents a model-based sliding mode control law for mechanical systems, which use shape memory alloys (SMAs) as actuators. The systems under consideration are assumed to be fully actuated and represented by unconstrained equations of motion. A system model is developed by combining the equations of motion with SMA heat convection, constitutive law, and phase transformation equations, which account for hysteresis. The control law is introduced using asymptotically stable second-order sliding surfaces. Robustness is guaranteed through the inclusion of modeling uncertainties in the controller development. The control law is developed assuming only positions are available for measurement. The unmeasured states, which include velocities and SMA temperatures and stresses, are estimated using an extended Kalman filter based on the nonlinear system model. The control law is applied to a three-link planar robot for position control problem. Simulation and experimental results show good agreement and verify the robustness of the control law despite significant modeling uncertainty. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...] [article] Sliding mode control of mechanical systems actuated by shape memory alloy [texte imprimé] / Hashem Ashrafiuon, Auteur ; Vijay Reddy Jala, Auteur . - 2009 . - 06 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 06 p. Mots-clés : temperature;  phase  transitions;  cooling;  control  equipment;  robots;  wire;  shape  memory  alloys;  stress;  equations  of  motion;  sliding  mode  control;  actuators;  convection;  modeling;  equations;  Kalman  filters;  position  control;  heating Résumé : This paper presents a model-based sliding mode control law for mechanical systems, which use shape memory alloys (SMAs) as actuators. The systems under consideration are assumed to be fully actuated and represented by unconstrained equations of motion. A system model is developed by combining the equations of motion with SMA heat convection, constitutive law, and phase transformation equations, which account for hysteresis. The control law is introduced using asymptotically stable second-order sliding surfaces. Robustness is guaranteed through the inclusion of modeling uncertainties in the controller development. The control law is developed assuming only positions are available for measurement. The unmeasured states, which include velocities and SMA temperatures and stresses, are estimated using an extended Kalman filter based on the nonlinear system model. The control law is applied to a three-link planar robot for position control problem. Simulation and experimental results show good agreement and verify the robustness of the control law despite significant modeling uncertainty. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...]

Reduced-Order model-based feedback control of flow over an obstacle using center manifold methods / Cosku Kasnakoglu in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 12 p. Titre : Reduced-Order model-based feedback control of flow over an obstacle using center manifold methods Type de document : texte imprimé Auteurs : Cosku Kasnakoglu, Auteur ; R. Chris Camphouse, Auteur ; Serrani, Andrea, Auteur Année de publication : 2009 Article en page(s) : 12 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : dynamics  (mechanics);  flow  (dynamics);  control  equipment;  design;  modeling;  optimization;  equations;  errors;  feedback;  manifolds Résumé : In this paper, we consider a boundary control problem governed by the two-dimensional Burgers’ equation for a configuration describing convective flow over an obstacle. Flows over obstacles are important as they arise in many practical applications. Burgers’ equations are also significant as they represent a simpler form of the more general Navier–Stokes momentum equation describing fluid flow. The aim of the work is to develop a reduced-order boundary control-oriented model for the system with subsequent nonlinear control law design. The control objective is to drive the full order system to a desired 2D profile. Reduced-order modeling involves the application of an L2 optimization based actuation mode expansion technique for input separation, demonstrating how one can obtain a reduced-order Galerkin model in which the control inputs appear as explicit terms. Controller design is based on averaging and center manifold techniques and is validated with full order numerical simulation. Closed-loop results are compared to a standard linear quadratic regulator design based on a linearization of the reduced-order model. The averaging∕center manifold based controller design provides smoother response with less control effort and smaller tracking error. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...] [article] Reduced-Order model-based feedback control of flow over an obstacle using center manifold methods [texte imprimé] / Cosku Kasnakoglu, Auteur ; R. Chris Camphouse, Auteur ; Serrani, Andrea, Auteur . - 2009 . - 12 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 12 p. Mots-clés : dynamics  (mechanics);  flow  (dynamics);  control  equipment;  design;  modeling;  optimization;  equations;  errors;  feedback;  manifolds Résumé : In this paper, we consider a boundary control problem governed by the two-dimensional Burgers’ equation for a configuration describing convective flow over an obstacle. Flows over obstacles are important as they arise in many practical applications. Burgers’ equations are also significant as they represent a simpler form of the more general Navier–Stokes momentum equation describing fluid flow. The aim of the work is to develop a reduced-order boundary control-oriented model for the system with subsequent nonlinear control law design. The control objective is to drive the full order system to a desired 2D profile. Reduced-order modeling involves the application of an L2 optimization based actuation mode expansion technique for input separation, demonstrating how one can obtain a reduced-order Galerkin model in which the control inputs appear as explicit terms. Controller design is based on averaging and center manifold techniques and is validated with full order numerical simulation. Closed-loop results are compared to a standard linear quadratic regulator design based on a linearization of the reduced-order model. The averaging∕center manifold based controller design provides smoother response with less control effort and smaller tracking error. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...]

Safe control of hopping in uneven terrain / Brian Howley in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 11 p. Titre : Safe control of hopping in uneven terrain Type de document : texte imprimé Auteurs : Brian Howley, Auteur ; Mark Cutkosky, Auteur Année de publication : 2009 Article en page(s) : 11 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : dynamics  (mechanics);  force;  machinery;  stairs;  motion;  safety;  robots;  thrust;  algorithms;  damping;  dynamic  systems;  robotics;  compression;  feedback;  springs;  steady  state;  stiffness Résumé : Using a classic problem from robotics of a vertical hopping machine, we demonstrate an approach for investigating the safety of a hybrid discrete/continuous dynamic system operating in an uncertain environment. The challenges imposed by the environment are expressed in terms of constraints imposed in the phase space of the system as it undergoes periodic motion. The approach is demonstrated first with a hopper that has state feedback to govern the timing of thrust and subsequently for a timer-based hopper. The latter case increases the dimensionality of the problem and must be treated numerically. However, the use of a multiresolution surface representation of the feasible regions in state space reduces the computational burden of the approach. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...] [article] Safe control of hopping in uneven terrain [texte imprimé] / Brian Howley, Auteur ; Mark Cutkosky, Auteur . - 2009 . - 11 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 11 p. Mots-clés : dynamics  (mechanics);  force;  machinery;  stairs;  motion;  safety;  robots;  thrust;  algorithms;  damping;  dynamic  systems;  robotics;  compression;  feedback;  springs;  steady  state;  stiffness Résumé : Using a classic problem from robotics of a vertical hopping machine, we demonstrate an approach for investigating the safety of a hybrid discrete/continuous dynamic system operating in an uncertain environment. The challenges imposed by the environment are expressed in terms of constraints imposed in the phase space of the system as it undergoes periodic motion. The approach is demonstrated first with a hopper that has state feedback to govern the timing of thrust and subsequently for a timer-based hopper. The latter case increases the dimensionality of the problem and must be treated numerically. However, the use of a multiresolution surface representation of the feasible regions in state space reduces the computational burden of the approach. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...]

Intermittent predictive steering control as an automobile driver model / Rene Roy in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 06 p. Titre : Intermittent predictive steering control as an automobile driver model Type de document : texte imprimé Auteurs : Rene Roy, Auteur ; Philippe Micheau, Auteur ; Paul Bourassa, Auteur Année de publication : 2009 Article en page(s) : 06 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : engineering  simulation;  vehicles;  automobiles;  errors;  predictive  control;  roads;  steering  wheels Résumé : The originality of this paper is the evaluation of intermittent control as a viable candidate to represent an automobile driver in a path tracking scenario. The control algorithm is based on general predictive control where the road curvature is considered known for a horizon in front of the automobile. The computed steering wheel command is used in an intermittent fashion, the intermittence period being one of the system parameter to study. Simulations are carried out and parameters of the driver, the automobile, and the road are varied. An intermittence period range giving satisfactory performances is observed. A comparison is made with actual car/driver behavior measurements for a lane change maneuver. It is concluded that, according to this driver model, there is a wide range of intermittence period that the automobile driver may be operating. Moreover, it is suggested to consider the intermittency of information as an important parameter for vehicle safety systems. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...] [article] Intermittent predictive steering control as an automobile driver model [texte imprimé] / Rene Roy, Auteur ; Philippe Micheau, Auteur ; Paul Bourassa, Auteur . - 2009 . - 06 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 06 p. Mots-clés : engineering  simulation;  vehicles;  automobiles;  errors;  predictive  control;  roads;  steering  wheels Résumé : The originality of this paper is the evaluation of intermittent control as a viable candidate to represent an automobile driver in a path tracking scenario. The control algorithm is based on general predictive control where the road curvature is considered known for a horizon in front of the automobile. The computed steering wheel command is used in an intermittent fashion, the intermittence period being one of the system parameter to study. Simulations are carried out and parameters of the driver, the automobile, and the road are varied. An intermittence period range giving satisfactory performances is observed. A comparison is made with actual car/driver behavior measurements for a lane change maneuver. It is concluded that, according to this driver model, there is a wide range of intermittence period that the automobile driver may be operating. Moreover, it is suggested to consider the intermittency of information as an important parameter for vehicle safety systems. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...]

Iterative and feedback control for hysteresis compensation in SMA / Kam K. Leang in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 06 p. Titre : Iterative and feedback control for hysteresis compensation in SMA Type de document : texte imprimé Auteurs : Kam K. Leang, Auteur ; Seth Ashley, Auteur ; Guy Tchoupo, Auteur Année de publication : 2009 Article en page(s) : 06 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : phase  transitions;  control  equipment;  actuators;  design;  errors;  feedback Résumé : This paper investigates the design of an iteration-based controller combined with feedback control to address the positioning error caused by hysteresis in a shape memory alloy (SMA) actuator. Without compensation, the positioning error due to hysteresis can be excessively large (greater than 20%), therefore limiting the performance of SMAs in positioning applications. An iterative controller based on the Preisach hysteresis model is used to compensate for the hysteresis. However, one of the major challenges with SMA at or near the phase-transition zones, from martensite to austenite and vice versa, is the output response is shown to be sensitive to small changes in the input. In practice, an iterative controller provides limited performance due to lack of robustness. It is demonstrated that combining a simple feedback controller with an iterative controller provides the needed robustness to enable high-precision tracking. Experimental results are presented that show maximum tracking error of 0.15% of the total displacement range—this value is approximately the noise level of the sensor measurement. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...] [article] Iterative and feedback control for hysteresis compensation in SMA [texte imprimé] / Kam K. Leang, Auteur ; Seth Ashley, Auteur ; Guy Tchoupo, Auteur . - 2009 . - 06 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 06 p. Mots-clés : phase  transitions;  control  equipment;  actuators;  design;  errors;  feedback Résumé : This paper investigates the design of an iteration-based controller combined with feedback control to address the positioning error caused by hysteresis in a shape memory alloy (SMA) actuator. Without compensation, the positioning error due to hysteresis can be excessively large (greater than 20%), therefore limiting the performance of SMAs in positioning applications. An iterative controller based on the Preisach hysteresis model is used to compensate for the hysteresis. However, one of the major challenges with SMA at or near the phase-transition zones, from martensite to austenite and vice versa, is the output response is shown to be sensitive to small changes in the input. In practice, an iterative controller provides limited performance due to lack of robustness. It is demonstrated that combining a simple feedback controller with an iterative controller provides the needed robustness to enable high-precision tracking. Experimental results are presented that show maximum tracking error of 0.15% of the total displacement range—this value is approximately the noise level of the sensor measurement. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...]

Lyapunov-based stabilization of MEMS relays / Y. Bastani in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 09 p. Titre : Lyapunov-based stabilization of MEMS relays Type de document : texte imprimé Auteurs : Y. Bastani, Auteur ; M. S. de Queiroz, Auteur Année de publication : 2009 Article en page(s) : 09 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : electric  potential;  control  equipment;  microelectromechanical  systems;  design;  electrodes;  signals;  simulation  results;  state  feedback;  velocity  measurement;  uncertainty Résumé : In this paper, nonlinear stabilizers are introduced for voltage-controlled microelectromechanical system (MEMS) relays. The control constructions follow a Lyapunov approach and are based on a nonlinear dynamic model applicable to the two types of MEMS relays—electrostatic and electromagnetic. Two control schemes are presented with the objectives of avoiding pull-in during the microrelay closing and improving the transient response during the microrelay opening. First, an adaptive state feedback stabilizer is proposed to compensate for parametric uncertainty in all mechanical parameters and selected electrical parameters while ensuring asymptotic regulation of the electrode opening and closing. Next, a model-based observer/stabilizer is proposed to account for the lack of velocity measurements. Simulations demonstrate the performance of the two control schemes in comparison to the typical open-loop operation of the MEMS relay. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...] [article] Lyapunov-based stabilization of MEMS relays [texte imprimé] / Y. Bastani, Auteur ; M. S. de Queiroz, Auteur . - 2009 . - 09 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 09 p. Mots-clés : electric  potential;  control  equipment;  microelectromechanical  systems;  design;  electrodes;  signals;  simulation  results;  state  feedback;  velocity  measurement;  uncertainty Résumé : In this paper, nonlinear stabilizers are introduced for voltage-controlled microelectromechanical system (MEMS) relays. The control constructions follow a Lyapunov approach and are based on a nonlinear dynamic model applicable to the two types of MEMS relays—electrostatic and electromagnetic. Two control schemes are presented with the objectives of avoiding pull-in during the microrelay closing and improving the transient response during the microrelay opening. First, an adaptive state feedback stabilizer is proposed to compensate for parametric uncertainty in all mechanical parameters and selected electrical parameters while ensuring asymptotic regulation of the electrode opening and closing. Next, a model-based observer/stabilizer is proposed to account for the lack of velocity measurements. Simulations demonstrate the performance of the two control schemes in comparison to the typical open-loop operation of the MEMS relay. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...]

Fast and robust synchronization of twin-gyro systems / S. M. Shahruz in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 05 p. Titre : Fast and robust synchronization of twin-gyro systems Type de document : texte imprimé Auteurs : S. M. Shahruz, Auteur Année de publication : 2009 Article en page(s) : 05 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : motion;  trusses  (building);  design;  displacement;  robustness;  synchronization Résumé : In this paper, design of control laws for V-gimbaled control-moment-gyro (CMG) devices is studied. Such a device has two gyros that are used to control the slewing motion of space truss arms. Control laws are designed to make the gyros of a CMG device track a desired function of time synchronously. Synchronous tracking makes the angular displacement of a truss arm track a desired function of time. Application of the synchronizing control laws to two-gyro systems in the absence and presence of parametric uncertainties and disturbances is studied. In both cases, the designed control laws achieve the desired goals. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...] [article] Fast and robust synchronization of twin-gyro systems [texte imprimé] / S. M. Shahruz, Auteur . - 2009 . - 05 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 05 p. Mots-clés : motion;  trusses  (building);  design;  displacement;  robustness;  synchronization Résumé : In this paper, design of control laws for V-gimbaled control-moment-gyro (CMG) devices is studied. Such a device has two gyros that are used to control the slewing motion of space truss arms. Control laws are designed to make the gyros of a CMG device track a desired function of time synchronously. Synchronous tracking makes the angular displacement of a truss arm track a desired function of time. Application of the synchronizing control laws to two-gyro systems in the absence and presence of parametric uncertainties and disturbances is studied. In both cases, the designed control laws achieve the desired goals. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...]

Local L2 gain of axial flow compressor control / Tiebao Yang in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 08 p. Titre : Local L2 gain of axial flow compressor control Type de document : texte imprimé Auteurs : Tiebao Yang, Auteur ; Xiang Chen, Auteur Année de publication : 2009 Article en page(s) : 08 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : control  equipment;  compressors;  axial  flow;  feedback Résumé : Feedback control has been pursued to stabilize the bifurcated operating solution near the rotating stall point in axial-flow compressors. These controllers can extend the stable operating range and hence improve engine performance. However, the local L2 gain of these controllers still remains unknown. In this paper, a family of Lyapunov functions is first constructed, and then the local L2 gain is derived through Hamilton–Jacobi–Bellman inequality for a class of stabilizing controllers with throttle position as actuator and pressure rise as measurement. The results obtained in this paper provide useful guidance for selecting the most robust controller from a given class of stabilizing controllers in terms of L2 gain. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...] [article] Local L2 gain of axial flow compressor control [texte imprimé] / Tiebao Yang, Auteur ; Xiang Chen, Auteur . - 2009 . - 08 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 08 p. Mots-clés : control  equipment;  compressors;  axial  flow;  feedback Résumé : Feedback control has been pursued to stabilize the bifurcated operating solution near the rotating stall point in axial-flow compressors. These controllers can extend the stable operating range and hence improve engine performance. However, the local L2 gain of these controllers still remains unknown. In this paper, a family of Lyapunov functions is first constructed, and then the local L2 gain is derived through Hamilton–Jacobi–Bellman inequality for a class of stabilizing controllers with throttle position as actuator and pressure rise as measurement. The results obtained in this paper provide useful guidance for selecting the most robust controller from a given class of stabilizing controllers in terms of L2 gain. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...]

Sensitivity analysis of combustion timing of homogeneous charge compression ignition gasoline engines / Chia-Jui Chiang in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 05 p. Titre : Sensitivity analysis of combustion timing of homogeneous charge compression ignition gasoline engines Type de document : texte imprimé Auteurs : Chia-Jui Chiang, Auteur ; Stefanopoulou, Anna G., Auteur Année de publication : 2009 Article en page(s) : 05 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : temperature;  combustion;  fuels;  engines;  cylinders;  exhaust  systems;  sensitivity  analysis;  gasoline  engines;  homogeneous  charge  compression  ignition  engines Résumé : The goal of this paper is to identify the dominant factors that should be included in a control oriented model in order to predict the start of combustion in a homogeneous charge compression ignition (HCCI) engine. Qualitative and quantitative information on the individual effects of fuel and exhaust gas recirculation on the HCCI combustion is provided. Using sensitivity analysis around a wide range of operating conditions of a single-cylinder port-injection gasoline HCCI engine, we find that temperature is the dominant factor in determining the start of combustion. Charge temperature thus becomes the “spark” in a HCCI engine. Therefore, a model without the composition terms should be adequate for model based regulation of the combustion timing in a port-injection gasoline HCCI engine with high dilution from the exhaust. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...] [article] Sensitivity analysis of combustion timing of homogeneous charge compression ignition gasoline engines [texte imprimé] / Chia-Jui Chiang, Auteur ; Stefanopoulou, Anna G., Auteur . - 2009 . - 05 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 05 p. Mots-clés : temperature;  combustion;  fuels;  engines;  cylinders;  exhaust  systems;  sensitivity  analysis;  gasoline  engines;  homogeneous  charge  compression  ignition  engines Résumé : The goal of this paper is to identify the dominant factors that should be included in a control oriented model in order to predict the start of combustion in a homogeneous charge compression ignition (HCCI) engine. Qualitative and quantitative information on the individual effects of fuel and exhaust gas recirculation on the HCCI combustion is provided. Using sensitivity analysis around a wide range of operating conditions of a single-cylinder port-injection gasoline HCCI engine, we find that temperature is the dominant factor in determining the start of combustion. Charge temperature thus becomes the “spark” in a HCCI engine. Therefore, a model without the composition terms should be adequate for model based regulation of the combustion timing in a port-injection gasoline HCCI engine with high dilution from the exhaust. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...]

Exemplaires

Bibliothèque Ecole Nationale Polytechnique d'Alger

Accueil

Se connecter

Météo

Adresse