446 results about "Actuator fault" patented technology

The invention relates to a spacecraft attitude integral sliding mode fault tolerance control method taking consideration of a performer fault and provides a robustness attitude active fault tolerance control method based on an integral sliding mode surface for problems of the performer fault, external disturbance and control moment amplitude limits in a spacecraft attitude control process. The method comprises steps that firstly, a spacecraft attitude dynamics model taking consideration of the performer fault and containing external disturbance is established; secondly, on the condition that a performer is not in fault, a designed nominal controller can guarantee system stability, and input saturation amplitude limits can be easily satisfied through adjusting controller parameters; lastly, the fault information is introduced to design an integral sliding mode controller, robustness of external disturbance and the performer fault can be effectively improved, system stability is analyzed on the basis of an Lyapunov method. The method is advantaged in that stability of the attitude control system is guaranteed when a spacecraft operating on orbit generates the performer fault, and relatively strong fault tolerance capability and external disturbance robustness are realized.

The invention discloses an active fault-tolerant control method for a lienar multi-agent tracking system on the basis of slip form control. A distributed fault-tolerant control strategy is put forwardby a distributed observer and a slip form control method by considering the executor faults, the sensor faults, the inherent nonlinearity and the leader unknown control input of a general linear multi-agent tracking system. Firstly, a state tracking error system is established by aiming at each follower, and a sensor fault signal is taken as an auxiliary state amount to establish an augmented tracking error system. In order to simultaneously estimate various faults and the leader unknown control input, an intermediate variable is imported. On the basis of neighbor set output information, a distributed observer is designed for the augmented tracking error system and the intermediate variable, and a global estimation error system is proved to be finally uniformly bounded. According to the obtained observation information, a nonlinear slip form surface is designed for the tracking error system of each follower agent, system robustness is enhanced, and the stability of a sliding mode is proved. According to the fault observation information and the neighbor set output information, a distributed slip form controller is put forward, the state of the error system is guaranteed to reach and be kept at the slip form surface within limited time, and therefore, the fault-tolerant tracking stability of the multi-agent system is realized. The method is used for the fault-tolerant control of the linear multi-agent tracking system with executor faults and sensor faults.

The invention relates to the technical field of satellite fault diagnosis and fault-tolerant control, and proposes a fault diagnosis method, which has very good robustness to external interference, isfree of influence of external interference in a fault diagnosis process, prevents generation of misinformation and missing report, and can effectively estimate fault severity. According to the satellite fault diagnosis and fault-tolerant control method based on a self-adaptive observer, first a satellite kinematics and dynamics model under an actuator fault and external interference influence isestablished to analyze influence of fault effective factors on a system; secondly, an observer is designed for a satellite fault system, a residual error evaluation function is established based on observer output and system actual output, an evaluation threshold value is obtained, and the purpose of fault detection is achieved; then, when occurrence of a fault is detected, a self-adaptive observer is designed to complete a fault diagnosis task; and finally, based on an estimated value of the fault, a finite time self-adaptive fault-tolerant controller is designed. The satellite fault diagnosis and fault-tolerant control method based on a self-adaptive observer is mainly applied to fault diagnosis and fault-tolerant control occasions.

The invention discloses a cooperative design method of fault detection filter and controller under DoS attack. The method is applied to a USV course control system, and is a cooperative design methodof a fault detection filter and an elastic event trigger controller based on a state observer, and the method comprises the following steps of: establishing a mathematical model based on the state observer USV control system under the influence of an actuator fault, a DoS attack and a network delay; introducing an event trigger mechanism related to the state of the observer, and establishing the model of the USV control system capable of simultaneously describing the time delay of the network transmission and the influence of the event trigger mechanism by using the time-delay system theory, determining an event trigger matrix W of the USV control system model, a state observer gain matrix L1, L2, a fault detection filter gain matrix V1, V2 and a controller gain matrix K; establishing a fault detection filter and an elastic event trigger controller based on a state observer under the DoS attack. The cooperative design method of fault detection filter and controller under DoS attack caneffectively resist the DoS attack and detect the fault in time.

The invention provides an aero-engine active fault-tolerant control method based on an error interval observer, and belongs to the technical field of aviation control. The method comprises the steps that an aero-engine tracks the state and the output of a reference model through an error feedback controller; an aero-engine control system with a disturbance signal and with an actuator fault and a sensor fault is compensated through a virtual sensor and a virtual actuator; the error between an aero-engine fault system and the reference model of the aero-engine fault system is observed through the error interval observer, and the error is fed back to the error feedback controller; and finally, the difference between the reference model output of the fault system and the virtual actuator output is used as a control signal to achieve active fault-tolerant control of the aero-engine. According to the method, when the actuator and the sensor of the aero-engine breaks down, even the disturbance signal exists, the system can be ensured to operate in a desired state without changing the controller, so that the system has good fault-tolerant capability and anti-interference capability.

The invention discloses a tracking fault-tolerant control method for a linear multi-agent system based on sliding mode control. A fault-tolerant control method based on the sliding mode control methodand adaptive control is proposed for the actuator fault of the linear multi-agent tracking system with external disturbance. Aiming at the actuator partial failure fault that may occur in the agent,the state error variable is defined according to the communication topology between multi-agents, the integral sliding mode surface is designed based on the error variable and sufficient conditions for sliding mode asymptotic stability are given. Then the unknown upper bound of the actuator fault is estimated by the adaptive method, and a sliding mode fault-tolerant controller is proposed to guarantee the tracking stability of the multi-agent system. The integral sliding mode surface is designed according to the state error variable between the multi-agents and the robustness of the system isenhanced, and the fault-tolerant control law having good fault-tolerant ability when the system has partial actuator failure fault and external disturbance is put forward and the tracking stability ofthe multi-agent system is improved. The fault-tolerant control method is used for fault tolerant control of the linear multi-agent system with the actuator failure fault and the external disturbance.

The invention provides a wind energy converting system sliding mode control method and device based on a T-S fuzzy model. To solve the problem of the fault of an actuator in a wind energy converting system, the T-S fuzzy model is utilized for describing a nonlinear wind energy converting system with uncertain actuator fault information, the approximation accuracy of a controlled object is improved, and a good model foundation is established for sliding mode control. Meanwhile, by means of a sliding mode controller designed based on the linear matrix inequality technology, the stability of the wind energy converting system is guaranteed, and the robustness and fault tolerance of the wind energy converting system are improved. The precise tracking of the rotating speed of a power generator and the electromagnetic torque can be achieved when the uncertain actuator fault exists in the wind energy converting system, and the maximum wind energy capturing of the wind speed below the rated value is achieved, and a valuable reference scheme is provided for efficient and stable running of the wind converting system.

The invention relates to the quadrotor unmanned aerial vehicle fault-tolerant control, and aims to realize attitude stability under the condition of an actuator fault of a quadrotor unmanned aerial vehicle. The technical scheme adopted by the invention is that an observer-based quadrotor unmanned aerial vehicle fault-tolerant control method includes the following steps: first defining an inertia coordinate system {I}, a body coordinate system {B} and a target coordinate system {Bd}, and through analysis of an action principle of the actuator on the quadrotor unmanned aerial vehicle, an unknown diagonal matrix is utilized to represent influence of an actuator fault on kinetic characteristics of the quadrotor unmanned aerial vehicle, and a nonlinear kinetic model when a fault occurs in the quadrotor unmanned aerial vehicle actuator is obtained; a unit quaternion-based attitude representation method is adopted; and an observer technology based on an immersion-invariant set method is adopted to observe the actuator. The observer-based quadrotor unmanned aerial vehicle fault-tolerant control method provided by the invention is mainly applied to quadrotor unmanned aerial vehicle design and control occasions.

The present invention relates to a spacecraft attitude fault-tolerant control method based on an iterative-learning disturbance observer. In order to solve the problem that actuator faults and external disturbances might occur during the attitude control process of the on-orbit operation of a spacecraft in the prior art, the invention provides an active fault-tolerant control method based on the iterative-learning observer. The method comprises the steps of firstly, establishing a dynamic model for the attitude control system of a spacecraft in considering the fault of an actuator in the attitude control system of the spacecraft and the external disturbance in the space of the spacecraft; secondly, estimating and designing a generalized disturbance torque of the iterative-learning disturbance observer composed of the actuator fault information and the external disturbance; finally, based on the estimated generalized interference, designing an active fault-tolerant controller. Based on the method, the stability of the attitude control system of the spacecraft, when the actuator of the spacecraft has a fault and the external disturbance exists in the space of the spacecraft, can be ensured. Meanwhile, the precision requirement of an actual control system is met. The method is strong in fault-tolerant ability and good in robustness for the external disturbance.

The invention discloses a finite time robust fault diagnosis design method for a leader-follower multi-agent system. The method includes the steps: firstly, building a multi-agent system connection diagram with a leader and showing the multi-agent system connection diagram by a directed graph to obtain a Laplacian matrix L of a follower and an adjacent matrix G of the leader; building a state equation and an output equation of each node flight control system and augmenting a state vector and a fault vector into new vectors; constructing a distributed error equation and a global error equation based on the directed graph for each node according to the built directed graph, constructing a finite time fault diagnosis observer of a flight control system based on finite time robust control, and performing finite time fault diagnosis for faults of a multi-agent executor based on the directed graph. Faults of an optional node of the control system or simultaneously occurring faults of a plurality of nodes are effectively and accurately diagnosed and estimated on line in finite time.

The invention relates to a nerve self-adaption fault-tolerant control method for train unknown perturbation. Based on the stress analysis of the longitudinal motion of a train, the longitudinal motion dynamic equation of the train is established. According to an actuator fault and the longitudinal motion dynamic equation of the train, a neural network radial basis function is used to approximate unknown additional resistance. The longitudinal motion dynamic equation of the train in the case of the actuator fault is established, and then a proportional-integral-differential sliding-mode surface is constructed. According to the longitudinal motion dynamic equation of the train in the case of the actuator fault, the closed-loop dynamic equation of train is established through an unknown self-adaption law and a controller. The stability of the system is proved, and then an observer and a controller equation are used to control the actual displacement and velocity of the train to approach expected displacement and velocity. According to the invention, the influence of the actuator fault on the train system can be compensated; the influence of additional resistance on the train system is attenuated or removed; and the train system has a good position and velocity tracking performance.

The invention relates to a robust fuzzy predictive fault-tolerant control method for an interval time-varying-delaying system. The robust fuzzy predictive fault-tolerant control method includes the following steps that firstly, a T-S fuzzy model of a nonlinear system is constructed; secondly, the constructed T-S fuzzy model is converted into an expanded T-S fuzzy model; thirdly, according to the constructed expanded T-S fuzzy model, a fault-tolerant controller that satisfies a control law is designed; and fourthly, a gain of the fault-tolerant controller is solved in a form of linear matrix inequality and the robust fuzzy predictive fault-tolerant control law is calculated. According to the robust fuzzy predictive fault-tolerant control method for the interval time-varying-delaying system,the robust fuzzy predictive fault-tolerant control method with time-delay dependence is provided according to the fact that a type of the industrial process has the characteristics such as nonlinearity, uncertainty, unknown disturbance, interval time-varying-delaying and partial actuator failure, thus the industrial process operates more smoothly and efficiently, the performance of a system is improved, and the fault tolerance of the system is increased.

The invention discloses a sliding-mode-based adaptive fault-tolerant control method for an uncertain time delay system. Considering that a quadrotor has an actuator fault under the conditions of inputtime delay and external disturbance, the fault-tolerant control method is proposed by combining adaptive control and sliding mode control. A time delay early predictor is designed to process the input time delay of the system; a matrix full-rank decomposition method and a sliding mode surface design method are adopted to solve the actuator fault problem; an adaptive sliding mode controller replaces a fault detection and isolation mechanism to automatically update and compensate for the actuator fault influence; the asymptotic stability of a closed-loop system is guaranteed with adaptive H2 performance. According to the method, by designing the adaptive sliding mode controller, the online adjustment of controller gain can be achieved, so that the proposed control law is optimal, the control precision and response speed of flight of the quadrotor are effectively improved, and a fault-tolerant controller design basis can be provided for the complex quadrotor with the actuator fault. Themethod is used for performing fault-tolerant control on the quadrotor with input time delay.

The invention discloses an unmanned surface ship track tracking method based on actuator faults, comprising the following steps: S1: analyzing various types of information of actuator faults, and modeling the actuator faults of an unmanned ship; S2: performing coordinate conversion of the velocity [Nu] in a mathematical model M1 of the unmanned surface ship in S1 to obtain a new velocity [Omega] and a new model M1'; S3: establishing an actuator fault observation device based on a track and speed tracking error model M in S2, and reconfiguring the actuator faults and external disturbance; S4: according to the track and speed tracking error model M in S2, establishing an integral sliding mode surface and a precise track tracking control law [Tau] of the unmanned surface ship with actuator faults; and S5: measuring the actual unmanned ship position to determine whether the unmanned surface ship reaches the end point of the actual track [Eta]d in S1.

The invention discloses an active formation fault-tolerant control method based on a fast adaptive technology. The active formation fault-tolerant control method comprises the steps that a laplacian matrix and a leader-following connection matrix of distributed multi-agent systems are achieved by constructing a connection diagram of multi-agent systems; according to a four-rotor aircraft model ofan existing nonlinear term, a corresponding observer and a fast adaptive fault estimator are constructed to predict the actual size of faults;alocal augmented system error dynamic equation and a wholeaugmented system error dynamic equation are constructed; Lyapunov function is constructed, the method that parameters in a computational controller and the fault estimator are calculated is derived and achieved through corresponding theories, and the requirements of formation control are finished under the action of actuator failure of the system and external interference. According to the activeformation fault-tolerant control method, adverse influence of the external interference on fault-tolerant control is completely eliminated at the theoretical level, performance of fault estimation isimproved, and the fault-tolerant control when the actuator fault occurs at any node of four-rotor aircraft formation or when the actuator fault occurs at multiple nodes at the same time is achieved.

The invention provides a heterogeneous fleet fault tolerance control method based on a variable time interval strategy. The method comprises the following steps of carrying out force analysis on longitudinal motion of vehicles and combining an actuator fault model to establish a vehicle longitudinal dynamics model under an actuator fault; constructing the variable time interval strategy with a lower boundary of fault information according to information of the vehicles; based on the constructed variable time interval strategy, establishing a proportional integral differential sliding mode surface and a coupled sliding mode surface; and selecting an appropriate Lyapunov function to design a fault-tolerant controller and an adaptive update rate, and proving finite time stability of a system.Traffic flow stability is proved based on the variable time interval strategy with the lower boundary of the fault information. Queue stability is proved based on the proportional integral differential sliding mode surface and the coupled sliding mode surface. Compared with a traditional variable time interval strategy, by using the technical scheme of the invention, a problem of a non-zero initial spacing error can be solved, and a critical traffic capacity can be increased.

The invention uses the idea of hierarchical structure control optimization to provide a manipulator actuator fault tolerant control system based on a double-layer structure and a method thereof, which belongs to the technical field of automatic control. In order to reduce the computational complexity and improve the instantaneity, a discrete system model under an actuator fault is established in an expansion manner through Taylor series. An FDD unit is designed to initiatively deal with a fault problem. The estimated fault information is introduced into a fault model to realize active fault tolerance. Uncertainties of the actual system are considered. A feedback correction mechanism is used for compensation. A manipulator fault tolerant controller is composed of a trajectory planning layer and a tracking control layer. According to different control objectives of each layer, a controller is designed separately, which is more specific to the problem. The fault tolerant control of the double-layer structure can deal with the existing system constraints, has strong robustness, can effectively solve the problem of the constant deviation fault of a complex manipulator actuator, and ensures the stability and the control performance of the whole system.

The invention discloses a spacecraft adaptive fault-tolerant attitude tracking control method with specified tracking performance. The method comprises steps: a kinematic model and a dynamic model ofthe spacecraft are built based on a certain amount of external disturbance on the spacecraft; based on the dynamic model of the spacecraft and based on unknown system fault on a spacecraft executor, an unknown actuator fault system model is built; based on the unknown actuator fault system model, a conversion error and a performance function are designed, and thus, the tracking error of the spacecrafts tends to be arbitrarily small minimum residual set under the specified tracking performance and the maximum overshoot; and the effects of the fault are compensated by estimating the boundary offault uncertainty, an adaptive fault-tolerant controller is designed, and the system tends to asymptotic stability. The method of the invention realizes high-precision system attitude tracking controlon the premise of ensuring the robustness of the system.

The invention discloses a robust fault-tolerant control method for small unmanned aerial vehicle flight control system. According to the discrete system with parametric uncertainties and time-varying delays in the case of actuator failure, a simulated-integral sliding mode prediction model is constructed. The model can ensure the global robustness of an entire dynamic process and deal with the influence of the fault incurred from the parametric uncertainties and time-varying delays on the progressive stability of the sliding mode. Through the use of the improved chaotic particle swarm optimization (PSO) algorithm to improve the rolling optimization process, the method can effectively avoid the problems that the traditional particle swarm algorithm is easy to fall into the local extreme point in the excellence seeking process and that the convergence rate is slow. In the invention, a new reference trajectory is proposed, which can reduce the influence of system uncertainty and time-varying delay to an acceptable range through compensation, and can also suppress the buffeting phenomenon of the sliding mode obviously. The invention is used for the robust fault-tolerant control for a discrete system with parametric uncertainties and time-varying delays in the case of actuator failure.

The invention discloses a fault detection method for a servo system based on an observer and relates to a fault detection method for a servo system, which belongs to the technical field of electromechanical failure detection. The method comprises the following steps of 1, modeling a dual-motor servo system as a linear model with an unknown input, an actuator fault and a sensor failure; 2, generating a residual signal by a Kalman filtering observer-based residual generator and conducting the fault detection and logic judgment; 3, through a norm-based residual evaluation function and a fixed threshold value, conducting the fault detection and logical judgment to detect a fault signal, and completing the fault detection of the dual-motor servo system. According to the technical scheme of the invention, the Kalman filtering observer-based residual generator reduces the influence of the external interference on the dual-motor servo system. Meanwhile, based on the norm-based residual evaluation function and the fixed threshold-value logical judgment, the fault signal of the system can be effectively detected.