2012 12th International Conference on Control Automation Robotics & Vision (ICARCV), 2012
ABSTRACT In this paper, we integrate information from a hybrid bond graph (HBG) model and discret... more ABSTRACT In this paper, we integrate information from a hybrid bond graph (HBG) model and discrete event systems (DES) into a fault diagnosis method for hybrid systems. In a pure HBG framework, mode change detection and isolation is handled by the mode change signature and the mode change signature matrix. In a DES approach, discrete states and faults are traced based on observable events and diagnosers. The integration of the two approaches is based on a new diagnoser that is driven by both, observable events and consistency indicators generated by continuous residuals. The proposed method allows not only to effectively trace the system mode, but also to decide whether this mode is faulty or normal. The new method is presented along with a theoretical example.
Turning-machining is an important manufacturing process, widely used in industry. The dynamic int... more Turning-machining is an important manufacturing process, widely used in industry. The dynamic interaction between the tool and the workpiece may cause regenerative chatter, that is associated with poor surface finish, reduced product quality and low productivity. The demand for accuracy motivates development of active vibration control methods based on realistic dynamic models of the turning process. This study investigates the performance of a novel active robust control law for chatter attenuation that is based on an extended dynamical model of the chatter regenerative process. The extended model describes an external turning process, and includes the influence of the workpiece elasticity and the actuator finite bandwidth.
This paper presents some useful results which follow from the particular structural properties of... more This paper presents some useful results which follow from the particular structural properties of a rigid robot model while the system is subject to the action of an output feedback. Given a rigid robot model, the controller ensures, in addition to the global asymptotic stability property, an eigenvalues assignment of the resulting linearized model within the stable region of the complex plane. In this way, required global and local control objectives can be achieved. Furthermore, the design of the controller is accomplished by applying a sort of a decoupling procedure that decomposes the entire nonlinear closed-loop system to a set of reduced-order nonlinear systems. The dependence of the eigenvalues of the linearized model on the model uncertainties is investigated. Simulation results that demonstrate the potential of the approach are presented.
This paper reveals some new structural properties of a rigid robot with state and output-based co... more This paper reveals some new structural properties of a rigid robot with state and output-based controllers. Applications of these properties allow one to design a controller that ensures both, global asymptotic stability of the nonlinear system and eigenvalues assignment of the resulting linear approximation within the stable region of the complex plane. Hence, required global and local control objective can be attained. Applications of the results to spacecraft attitude control are demonstrated.
In this note, we consider the application of a velocity-free controller for attitude regulation o... more In this note, we consider the application of a velocity-free controller for attitude regulation of a rigid spacecraft with gas jet actuators when the effects of time-delays in the feedback loop are taken into consideration. Simple sufficient conditions for exponential stability are presented. Some structural properties of the resulting closed-loop system are studied, and relevant design tools are demonstrated.
This paper describes a methodology for simultaneous identification of fault parame-ters and mode ... more This paper describes a methodology for simultaneous identification of fault parame-ters and mode switching events for hybrid systems. The method is developed based on the notion of Global Analytical Redundancy Relations (GARR) from the bond graph model of the hybrid system. A unified formula with mode change time sequence and initial mode coefficients (IMC) is derived to represent the mode switching. It employs Genetic Algorithm (GA) to search for fault parameters and mode switching time stamps. Fault parameters, mode switching time stamps and all IMC are encoded into one chromosome as a potential solution of the identification process. GARRs are used as a fitness index in GA search. An electro-hydraulic system of vehicle is studied to illustrate the efficiency of the proposed algorithm.
... Israel (e-mail: arogeti@bgu.ac.il). M. Luo is with the Singapore Institute of Manufacturing T... more ... Israel (e-mail: arogeti@bgu.ac.il). M. Luo is with the Singapore Institute of Manufacturing Technology, 71 Nanyang Drive, Singapore 638075 (e-mail: mluo@SIMTech.a-star.edu.sg) complex hybrid system, based on the bond ...
Recently, a Bond-graph based Fault Detection and Isolation (FDI) framework has been developed wit... more Recently, a Bond-graph based Fault Detection and Isolation (FDI) framework has been developed with a new concept of Global Analytical Redundancy Relations (GARRs). This new concept allows the fault diagnosis for hybrid systems which consist of both continuous dynamics and discrete modes. In this paper the newly developed method is studied in details using an electro-hydraulic steering system of a CyCab mobile robot. GARRs are derived systematically from a Hybrid Bond Graph (HBG) model with a specific causality assignment. FDI is applied, experimental setup is described, and results are discussed.
Manufacturing shop floor dynamics such as tool breakage or machine performance degradation or bre... more Manufacturing shop floor dynamics such as tool breakage or machine performance degradation or breakdown will disrupt the execution of planned production schedules. An intelligent shop floor is one that is able to react to changes that are occurring in a positive way. To give the early warning of the system/equipment health conditions and job execution capability to the supervisory control will improve the productivity and efficiency of the shop floor. This paper presents a new concept called iDiagnosis & Prognosis - an intelligent diagnosis, prognosis, manufacturing system condition and job execution capability assessment system based on the Internet, Web service and agent technologies. The paper introduces the basic concept of iDiagnosis & Prognosis. The proposed approach provides system functions, architecture and system components. The iDiagnosis & Prognosis dynamic model encompasses both information flow and event handling of the shop floor dynamics.
Manufacturing shop floor dynamics such as machine performance degradation or breakdown will affec... more Manufacturing shop floor dynamics such as machine performance degradation or breakdown will affect the execution of planned production schedules. An intelligent shop floor is able to react to changes in a positive way. To give the early warning of the system/equipment health conditions and mission execution capability to the supervisory control will improve the productivity and efficiency of the shop
IEEE Transactions Automation Science and Engineering, 2010
ABSTRACT This research result consists of two parts: one is general theory on causality assignmen... more ABSTRACT This research result consists of two parts: one is general theory on causality assignment for hybrid bond graph (HBG) and another is application of this concept to the quantitative fault diagnosis. From Low et al., 2008, a foundation for quantitative bond graph-based fault detection and isolation (FDI) design using HBG is laid. Useful causality properties pertaining to the HBG from FDI perspectives, and the concept of diagnostic hybrid bond graph (DHBG) which is advantageous for efficient and effective FDI applications are proposed. This paper is a continuation of our previous paper (Low et al., 2008). Here, the DHBG is exploited to analyze the hybrid system's fault detectability and fault isolability. Additionally, a quantitative FDI framework for effective fault diagnosis for hybrid systems is proposed. Simulation and experimental results are presented to validate some key concepts of the quantitative hybrid bond graph-based FDI framework.
2012 12th International Conference on Control Automation Robotics & Vision (ICARCV), 2012
ABSTRACT In this paper, we integrate information from a hybrid bond graph (HBG) model and discret... more ABSTRACT In this paper, we integrate information from a hybrid bond graph (HBG) model and discrete event systems (DES) into a fault diagnosis method for hybrid systems. In a pure HBG framework, mode change detection and isolation is handled by the mode change signature and the mode change signature matrix. In a DES approach, discrete states and faults are traced based on observable events and diagnosers. The integration of the two approaches is based on a new diagnoser that is driven by both, observable events and consistency indicators generated by continuous residuals. The proposed method allows not only to effectively trace the system mode, but also to decide whether this mode is faulty or normal. The new method is presented along with a theoretical example.
Turning-machining is an important manufacturing process, widely used in industry. The dynamic int... more Turning-machining is an important manufacturing process, widely used in industry. The dynamic interaction between the tool and the workpiece may cause regenerative chatter, that is associated with poor surface finish, reduced product quality and low productivity. The demand for accuracy motivates development of active vibration control methods based on realistic dynamic models of the turning process. This study investigates the performance of a novel active robust control law for chatter attenuation that is based on an extended dynamical model of the chatter regenerative process. The extended model describes an external turning process, and includes the influence of the workpiece elasticity and the actuator finite bandwidth.
This paper presents some useful results which follow from the particular structural properties of... more This paper presents some useful results which follow from the particular structural properties of a rigid robot model while the system is subject to the action of an output feedback. Given a rigid robot model, the controller ensures, in addition to the global asymptotic stability property, an eigenvalues assignment of the resulting linearized model within the stable region of the complex plane. In this way, required global and local control objectives can be achieved. Furthermore, the design of the controller is accomplished by applying a sort of a decoupling procedure that decomposes the entire nonlinear closed-loop system to a set of reduced-order nonlinear systems. The dependence of the eigenvalues of the linearized model on the model uncertainties is investigated. Simulation results that demonstrate the potential of the approach are presented.
This paper reveals some new structural properties of a rigid robot with state and output-based co... more This paper reveals some new structural properties of a rigid robot with state and output-based controllers. Applications of these properties allow one to design a controller that ensures both, global asymptotic stability of the nonlinear system and eigenvalues assignment of the resulting linear approximation within the stable region of the complex plane. Hence, required global and local control objective can be attained. Applications of the results to spacecraft attitude control are demonstrated.
In this note, we consider the application of a velocity-free controller for attitude regulation o... more In this note, we consider the application of a velocity-free controller for attitude regulation of a rigid spacecraft with gas jet actuators when the effects of time-delays in the feedback loop are taken into consideration. Simple sufficient conditions for exponential stability are presented. Some structural properties of the resulting closed-loop system are studied, and relevant design tools are demonstrated.
This paper describes a methodology for simultaneous identification of fault parame-ters and mode ... more This paper describes a methodology for simultaneous identification of fault parame-ters and mode switching events for hybrid systems. The method is developed based on the notion of Global Analytical Redundancy Relations (GARR) from the bond graph model of the hybrid system. A unified formula with mode change time sequence and initial mode coefficients (IMC) is derived to represent the mode switching. It employs Genetic Algorithm (GA) to search for fault parameters and mode switching time stamps. Fault parameters, mode switching time stamps and all IMC are encoded into one chromosome as a potential solution of the identification process. GARRs are used as a fitness index in GA search. An electro-hydraulic system of vehicle is studied to illustrate the efficiency of the proposed algorithm.
... Israel (e-mail: arogeti@bgu.ac.il). M. Luo is with the Singapore Institute of Manufacturing T... more ... Israel (e-mail: arogeti@bgu.ac.il). M. Luo is with the Singapore Institute of Manufacturing Technology, 71 Nanyang Drive, Singapore 638075 (e-mail: mluo@SIMTech.a-star.edu.sg) complex hybrid system, based on the bond ...
Recently, a Bond-graph based Fault Detection and Isolation (FDI) framework has been developed wit... more Recently, a Bond-graph based Fault Detection and Isolation (FDI) framework has been developed with a new concept of Global Analytical Redundancy Relations (GARRs). This new concept allows the fault diagnosis for hybrid systems which consist of both continuous dynamics and discrete modes. In this paper the newly developed method is studied in details using an electro-hydraulic steering system of a CyCab mobile robot. GARRs are derived systematically from a Hybrid Bond Graph (HBG) model with a specific causality assignment. FDI is applied, experimental setup is described, and results are discussed.
Manufacturing shop floor dynamics such as tool breakage or machine performance degradation or bre... more Manufacturing shop floor dynamics such as tool breakage or machine performance degradation or breakdown will disrupt the execution of planned production schedules. An intelligent shop floor is one that is able to react to changes that are occurring in a positive way. To give the early warning of the system/equipment health conditions and job execution capability to the supervisory control will improve the productivity and efficiency of the shop floor. This paper presents a new concept called iDiagnosis & Prognosis - an intelligent diagnosis, prognosis, manufacturing system condition and job execution capability assessment system based on the Internet, Web service and agent technologies. The paper introduces the basic concept of iDiagnosis & Prognosis. The proposed approach provides system functions, architecture and system components. The iDiagnosis & Prognosis dynamic model encompasses both information flow and event handling of the shop floor dynamics.
Manufacturing shop floor dynamics such as machine performance degradation or breakdown will affec... more Manufacturing shop floor dynamics such as machine performance degradation or breakdown will affect the execution of planned production schedules. An intelligent shop floor is able to react to changes in a positive way. To give the early warning of the system/equipment health conditions and mission execution capability to the supervisory control will improve the productivity and efficiency of the shop
IEEE Transactions Automation Science and Engineering, 2010
ABSTRACT This research result consists of two parts: one is general theory on causality assignmen... more ABSTRACT This research result consists of two parts: one is general theory on causality assignment for hybrid bond graph (HBG) and another is application of this concept to the quantitative fault diagnosis. From Low et al., 2008, a foundation for quantitative bond graph-based fault detection and isolation (FDI) design using HBG is laid. Useful causality properties pertaining to the HBG from FDI perspectives, and the concept of diagnostic hybrid bond graph (DHBG) which is advantageous for efficient and effective FDI applications are proposed. This paper is a continuation of our previous paper (Low et al., 2008). Here, the DHBG is exploited to analyze the hybrid system's fault detectability and fault isolability. Additionally, a quantitative FDI framework for effective fault diagnosis for hybrid systems is proposed. Simulation and experimental results are presented to validate some key concepts of the quantitative hybrid bond graph-based FDI framework.
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Papers by Shai Arogeti