This paper establishes a formal model for hybrid diagnosis, novelfeatures including: (1) It provides a unified theoretical framework for utilizing de-vice models and heuristics in diagnosis, which naturally integrates...This paper establishes a formal model for hybrid diagnosis, novelfeatures including: (1) It provides a unified theoretical framework for utilizing de-vice models and heuristics in diagnosis, which naturally integrates all the importantcomponents of diagnosis - the structural and behavioral description of devices, faultmodes, the lower and upper fault bounds, fault possibilities and heuristic rules -into a diagnostic system. Device models predict outputs from inputs, heuristic rulesinfer the possibilities of certain components being faulty from symptoms, and yetthe combination of both constrains each other for us to reduce the hypothesis space.(2) It presents a typical way of modeling behavior of devices, to which the key isthe introduction of I-O functions with indefinite inputs/outputs. (3) It can easily beimplemented over a forward-chaining inference engine.展开更多
For a class of non-uniform output sampling hybrid system with actuator faults and bounded disturbances,an iterative learning fault diagnosis algorithm is proposed.Firstly,in order to measure the impact of fault on sys...For a class of non-uniform output sampling hybrid system with actuator faults and bounded disturbances,an iterative learning fault diagnosis algorithm is proposed.Firstly,in order to measure the impact of fault on system between every consecutive output sampling instants,the actual fault function is transformed to obtain an equivalent fault model by using the integral mean value theorem,then the non-uniform sampling hybrid system is converted to continuous systems with timevarying delay based on the output delay method.Afterwards,an observer-based fault diagnosis filter with virtual fault is designed to estimate the equivalent fault,and the iterative learning regulation algorithm is chosen to update the virtual fault repeatedly to make it approximate the actual equivalent fault after some iterative learning trials,so the algorithm can detect and estimate the system faults adaptively.Simulation results of an electro-mechanical control system model with different types of faults illustrate the feasibility and effectiveness of this algorithm.展开更多
A dynamically reconfigurable system can change its configuration during operation, and studies of such systems are being carried out in many fields. In particular, medical technology and aerospace engineering must ens...A dynamically reconfigurable system can change its configuration during operation, and studies of such systems are being carried out in many fields. In particular, medical technology and aerospace engineering must ensure system safety because any defect will have serious consequences. Model checking is a method for verifying system safety. In this paper, we propose the Dynamic Linear Hybrid Automaton (DLHA) specification language and show a method to analyze reachability for a system consisting of several DLHAs.展开更多
文摘This paper establishes a formal model for hybrid diagnosis, novelfeatures including: (1) It provides a unified theoretical framework for utilizing de-vice models and heuristics in diagnosis, which naturally integrates all the importantcomponents of diagnosis - the structural and behavioral description of devices, faultmodes, the lower and upper fault bounds, fault possibilities and heuristic rules -into a diagnostic system. Device models predict outputs from inputs, heuristic rulesinfer the possibilities of certain components being faulty from symptoms, and yetthe combination of both constrains each other for us to reduce the hypothesis space.(2) It presents a typical way of modeling behavior of devices, to which the key isthe introduction of I-O functions with indefinite inputs/outputs. (3) It can easily beimplemented over a forward-chaining inference engine.
基金supported by the National Natural Science Foundation of China(61273070,61203092)the Enterprise-college-institute Cooperative Project of Jiangsu Province(BY2015019-21)+1 种基金111 Project(B12018)the Fun-damental Research Funds for the Central Universities(JUSRP51733B)
文摘For a class of non-uniform output sampling hybrid system with actuator faults and bounded disturbances,an iterative learning fault diagnosis algorithm is proposed.Firstly,in order to measure the impact of fault on system between every consecutive output sampling instants,the actual fault function is transformed to obtain an equivalent fault model by using the integral mean value theorem,then the non-uniform sampling hybrid system is converted to continuous systems with timevarying delay based on the output delay method.Afterwards,an observer-based fault diagnosis filter with virtual fault is designed to estimate the equivalent fault,and the iterative learning regulation algorithm is chosen to update the virtual fault repeatedly to make it approximate the actual equivalent fault after some iterative learning trials,so the algorithm can detect and estimate the system faults adaptively.Simulation results of an electro-mechanical control system model with different types of faults illustrate the feasibility and effectiveness of this algorithm.
文摘A dynamically reconfigurable system can change its configuration during operation, and studies of such systems are being carried out in many fields. In particular, medical technology and aerospace engineering must ensure system safety because any defect will have serious consequences. Model checking is a method for verifying system safety. In this paper, we propose the Dynamic Linear Hybrid Automaton (DLHA) specification language and show a method to analyze reachability for a system consisting of several DLHAs.