Moshu Qian

Active fault tolerant control design for reusable launch vehicle using adaptive sliding mode technique

Abstract In this paper, the problem of active fault tolerant control for a reusable launch vehicle (RLV) with actuator fault using both adaptive and sliding mode techniques is investigated. Firstly, the kinematic equations and dynamic equations of RLV are given, which represent the characteristics of RLV in reentry flight phase. For the dynamic model of RLV in faulty case, a fault detection scheme is proposed by designing a nonlinear fault detection observer. Then, an active fault tolerant tracking strategy for RLV attitude control systems is presented by making use of both adaptive control and sliding mode control techniques, which can guarantee the asymptotic output tracking of the closed-loop attitude control systems in spite of actuator fault. Finally, simulation results are given to demonstrate the effectiveness of the developed fault tolerant control scheme.

Passive fault tolerant control approach for hypersonic vehicle with actuator loss of effectiveness faults

In this paper, a passive fault tolerant controller is designed for a hypersonic vehicle with bounded external disturbances and unknown actuator loss of effectiveness faults. The nonlinear attitude dynamics models of hypersonic vehicle are firstly given, when some actuator occur unknown loss of effectiveness faults, the faulty attitude control systems of hypersonic vehicle are established, which could be divided into the outer attitude angle loop and the inner angle velocity loop based on the timescale separation principle. By using terminal sliding mode technique, a passive fault tolerant control approach is developed, which guarantees that the closed-loop attitude control systems of hypersonic vehicle in actuator loss of effectiveness fault case are stable. Finally, simulation results are presented to demonstrate the feasibility of the proposed fault tolerant control approach.

New Fault Tolerant Control Scheme Design for Reusable Launch Vehicle Attitude Control Systems

Abstract In this study, a new fault tolerant control approach is proposed for a class of reusable launch vehicle (RLV) attitude control systems. The nonlinear attitude control systems of RLV are given, which represent the dynamic characteristics of RLV in ascent and reentry phases. When actuator loss-of-effectiveness (LOE) faults occur, a new fault tolerant control design is presented using the dynamic surface control technique. Based on Lyapunov stability theory, the ultimate uniform boundedness of the faulty attitude control systems of RLV is analyzed. Finally, simulation results are given to illustrate the efficiency of the proposed approach.

Active fault-tolerant control approach design for rigid spacecraft with multiple actuator faults

In this study, the active fault-tolerant control problem is investigated for a rigid spacecraft in the presence of inertia uncertainty, external disturbance, multiple actuator faults and actuator saturation. The attitude system model of spacecraft and actuator fault model are first given. A sliding mode–based fault detection observer and a radial basis function neural networks–based fault estimation observer are designed to detect the time of actuator fault occurred and estimate the amplitude of unknown fault, respectively. On that basis, an active fault-tolerant control scheme is proposed to accommodate the effects of multiple actuator faults, and it guarantees that the state trajectory of attitude systems without actuator saturation converges to a neighborhood of the origin in finite time. Another active fault-tolerant control scheme is further proposed in actuator saturation constraint case; it ensures that all the closed-loop signals are finite time convergence. Finally, simulation results are given to illustrate the effectiveness of the proposed fault-tolerant control approach.

Active FTC approach design for a class of nonlinear flight control systems with actuator faults

In this paper, an active fault tolerant controller is designed for a class of nonlinear flight control systems with bounded external disturbances and unknown actuator effectiveness loss faults. Firstly, the nonlinear flight control system models of an aircraft are given. When some actuators occur the unknown loss of effectiveness faults, the faulty flight control systems is further established. To obtain the accurately fault estimated value, an adaptive fault estimation observer is designed for the faulty flight control systems. Then, an active fault tolerant controller design approach is proposed by using terminal sliding mode technique and the obtained estimated value of unknown actuator fault, which could asymptotically accommodate the effects of actuator faults and guarantees the stability of the closed-loop flight control systems in the case of actuator loss of effectiveness faults. Finally, these results in simulation indicate the efficiency of our presented fault tolerant control (FTC) scheme.

Active Fault Tolerant Control for Flexible Spacecraft with Sensor Faults Using Adaptive Integral Sliding Mode

In this paper, an active fault tolerant attitude control system is provided for a flexible spacecraft to accommodate the unknown sensor faults. Firstly, a model-based fault estimation technique developed into the process behavior by using a virtual filter and an adaptive observer, and then estimating the amplitude magnitude for the faulty sensor in the presence of system disturbance and parameter uncertainty. Next, reconfigurable attitude controller is developed by combining both integral sliding mode control and linear matrix inequality technique. Meanwhile, the stability of the closed loop attitude systems under the designed active fault tolerant control (FTC) scheme is analyzed by utilizing Lyapunov approach. Finally, the effectiveness of the proposed fault tolerant scheme has justified by simulation result on a flexible spacecraft attitude control systems with a time varying sensor fault.

Adaptive fault tolerant control design for UAV with multiple actuator faults

This paper addresses an adaptive fault tolerant flight control design for an unmanned aerial vehicle (UAV) in the presence of multiple actuator faults. With a reference model and control allocation implemented to evaluate dynamic tracking error performance of flight control systems (FCS) in fault free case, the proposed control can converge to an optimal solution and make faulty FCS asymptotically track a reference system online. Finally, simulation results are given to demonstrate the effectiveness of the proposed development.

Terminal sliding mode fault tolerant control design for hypersonic vehicle under angular velocity constraints

In this study, a terminal sliding mode fault tolerant control approach is presented for the hypersonic vehicle attitude systems with actuator loss of effectiveness fault and external disturbance in the case of angular velocity constraints. Firstly, the nonlinear attitude systems of hypersonic vehicle are given, which contains dynamics equations and kinematics equations. For the aim of fault tolerant control, the actuator loss of effectiveness fault model is introduced. Secondly, the fault tolerant tracking controller is designed for the faulty attitude systems of hypersonic vehicle under angular velocity constraint case using terminal sliding mode technique. Meanwhile, the Lyapunov theory is used to analyze the stability of the closed-loop attitude systems. Finally, simulation for the attitude dynamics models show the feasibility of the proposed fault tolerant scheme.

Adaptive dynamic surface tracking scheme design for rössler chaotic systems with control input saturation

In this paper, an adaptive tracking control approach is developed for a class of rössler chaotic systems with control input saturation by using dynamic surface control technique. Firstly, the nonlinear dynamical models of rössler chaotic systems with control input saturation are given. Then, an adaptive tracking controller is designed in the framework of dynamic surface control, which guaranteed that all the signals of the closed-loop control systems are ultimately uniformly bounded. A compensation control input term is introduced in the design of adaptive tracking controller in order to solve the control input saturation problem. Further, the stability of the closed-loop control systems is analyzed based on the Lyapunov stability theory. Finally, simulation results are given to illustrate the feasibility of the proposed approach.

Observer-based H-infinity tracking control design for a linearized hypersonic vehicle model with external disturbance

In this study, the H-infinity tracking control problem of a linearized hypersonic vehicle model with the bounded external disturbance is investigated. Firstly, the nonlinear longitudinal dynamics of hypersonic vehicle is linearized as a linear time-invariant system with the bounded external disturbance, a reference model is introduced for the aim of tracking control. And then an observer-based output feedback tracking controller design approach is proposed by using the linear matrix inequalities (LMIs) technique. The asymptotical stability of the closed-loop system is analyzed in the framework of Lyapunov method. Finally, the simulation results are given to illustrate the applicability of the developed control approach.