This paper proposes a fault-tolerant strategy for hypersonic reentry vehicles with mixed aerodynamic surfaces and reaction control systems(RCS) under external disturbances and subject to actuator faults.Aerodynamic ...This paper proposes a fault-tolerant strategy for hypersonic reentry vehicles with mixed aerodynamic surfaces and reaction control systems(RCS) under external disturbances and subject to actuator faults.Aerodynamic surfaces are treated as the primary actuator in normal situations,and they are driven by a continuous quadratic programming(QP) allocator to generate torque commanded by a nonlinear adaptive feedback control law.When aerodynamic surfaces encounter faults,they may not be able to provide sufficient torque as commanded,and RCS jets are activated to augment the aerodynamic surfaces to compensate for insufficient torque.Partial loss of effectiveness and stuck faults are considered in this paper,and observers are designed to detect and identify the faults.Based on the fault identification results,an RCS control allocator using integer linear programming(ILP) techniques is designed to determine the optimal combination of activated RCS jets.By treating the RCS control allocator as a quantization element,closed-loop stability with both continuous and quantized inputs is analyzed.Simulation results verify the effectiveness of the proposed method.展开更多
Reaction control system(RCS) is a powerful and efficient actuator for space vehicles attitude control, which is typically characterized as a pulsed unilateral effector only with two states(off/on). Along with inevitab...Reaction control system(RCS) is a powerful and efficient actuator for space vehicles attitude control, which is typically characterized as a pulsed unilateral effector only with two states(off/on). Along with inevitable internal uncertainties and external disturbances in practice, this inherent nonlinear character always hinders space vehicles autopilot from pursuing precise tracking performance. Compared to most of pre-existing methodologies that passively suppress the uncertainties and disturbances, a design based on predictive functional control(PFC) and generalized extended state observer(GESO) is firstly proposed for three-axis RCS control system to actively reject that with no requirement for additional fuel consumption. To obtain a high fidelity predictive model on which the performance of PFC greatly depends, the nonlinear coupling multiple-input multiple-output(MIMO) flight dynamics model is parameterized as a state-dependent coefficient form. And based on that, a MIMO PFC algorithm in state space domain for a plant of arbitrary orders is deduced in this paper.The internal uncertainties and external disturbances are lumped as a total disturbance, which is estimated and cancelled timely to further enhance the robustness. The continuous control command synthesised by above controller-rejector tandem is finally modulated by pulse width pulse frequency modulator(PWPF) to on-off signals to meet RCS requirement. The robustness and feasibility of the proposed design are validated by a series of performance comparison simulations with some prominent methods in the presence of significant perturbations and disturbances, as well as measurement noise.展开更多
针对RLV(Reusable Launch Vehicle)的再入控制提出了一种基于模糊逻辑的RCS(Reaction Control System).详细分析了RCS控制特性,建立了基于效率系数以及继电特性的RCS模型,提出了一种基于Mamdani模型的模糊逻辑三通道RCS控制器,该控制器...针对RLV(Reusable Launch Vehicle)的再入控制提出了一种基于模糊逻辑的RCS(Reaction Control System).详细分析了RCS控制特性,建立了基于效率系数以及继电特性的RCS模型,提出了一种基于Mamdani模型的模糊逻辑三通道RCS控制器,该控制器利用专家控制经验,根据姿态角及角速率的偏差,产生不同的RCS控制指令输出给三通道对飞行器进行姿态控制.通过六自由度非线性仿真,验证了该控制系统与PID(Proportional-Integral-D ifferential)控制器相比具有更好的跟踪性能,且RCS的控制输出效率也更高.展开更多
针对多枚子弹在稀薄大气层的编队飞行控制问题,进行了相关研究。基于反作用控制系统(reaction control system,RCS)的姿轨控制技术,提出一种新的协同编队策略,满足所需的空间构型约束,以实现对目标的精确定位。考虑最优空间构型约束,完...针对多枚子弹在稀薄大气层的编队飞行控制问题,进行了相关研究。基于反作用控制系统(reaction control system,RCS)的姿轨控制技术,提出一种新的协同编队策略,满足所需的空间构型约束,以实现对目标的精确定位。考虑最优空间构型约束,完成了协同制导方案设计,并利用经典的比例积分微分(proportion integration differentiation,PID)控制律实现了对子弹姿态的稳定跟踪和控制。采用脉宽脉频(pulse width pulse frequency,PWPF)调制技术将连续的控制量转换成等效的喷管开关指令,在保证姿态稳定控制的前提下有效减小了发动机的燃料消耗。仿真结果表明,该协同制导控制策略可保证子弹在飞行过程中的姿态稳定,并使其空间构型逼近最佳构型。展开更多
高超声速飞行器再入段初期,所处大气环境空气稀薄,空气舵已无法提供足够力矩来维持姿态稳定,因此就需要反作用控制系统(Reaction Control System,RCS)来提供姿态稳定力矩。针对给定的飞行器RCS八喷管配置方案,基于查表法和脉宽调制,提...高超声速飞行器再入段初期,所处大气环境空气稀薄,空气舵已无法提供足够力矩来维持姿态稳定,因此就需要反作用控制系统(Reaction Control System,RCS)来提供姿态稳定力矩。针对给定的飞行器RCS八喷管配置方案,基于查表法和脉宽调制,提出了一种能够维持飞行器系统姿态稳定的静态指令分配方法。给出了高超声速飞行器六自由度状态方程,采用一阶滑模控制算法进行姿态稳定控制;基于查表法思想和冲量等效的脉宽调制原理,完成了无故障情况下八喷管指令分配组合表的设计,并根据工程实际对组合表进行容错优化;设计了能够对单推力器发生卡死故障具有容错性的指令分配优化组合表,并采用脉宽调制方法对控制指令进行调制从而获得推力器的开关指令。仿真验证了该指令分配方法能够维持系统姿态稳定,提高控制系统的控制效率,有效解决了八喷管配置以及单喷管卡死故障情况下的指令分配问题。展开更多
This paper proposes a novel composite dual-control bycombing the integral sliding mode control (ISMC) method basedon the finite time convergence theory with extended state observer(ESO) for a tracking problem of a...This paper proposes a novel composite dual-control bycombing the integral sliding mode control (ISMC) method basedon the finite time convergence theory with extended state observer(ESO) for a tracking problem of a missile with tail fins and reactionjetcontrol system (RCS). First, the ISMC method based on finitetime convergence is utilized to design the control law of tail fins andthe pulse control of RCS for the dual-control system, ensuring thesystem with rapid response and high accuracy of tracking. Then,ESO is employed for the estimation of aerodynamic disturbancesinfluenced by the airflow of thruster jets. With the characteristicof high accuracy estimation of ESO, the chattering free trackingperformance of the attack angle command and the robustnessof the control law are achieved. Meanwhile, the stability of thedual-control system is analyzed based on finite time convergencestability theorem and Lyapunov’s theorem. Finally, numerical simulationsdemonstrate the effectiveness of the proposed design.展开更多
基金supported by the National Natural Science Foundation of China(Nos.61374116 and 61533009)the Six Talent Peaks Project in Jiangsu Province(No.HKHT010)
文摘This paper proposes a fault-tolerant strategy for hypersonic reentry vehicles with mixed aerodynamic surfaces and reaction control systems(RCS) under external disturbances and subject to actuator faults.Aerodynamic surfaces are treated as the primary actuator in normal situations,and they are driven by a continuous quadratic programming(QP) allocator to generate torque commanded by a nonlinear adaptive feedback control law.When aerodynamic surfaces encounter faults,they may not be able to provide sufficient torque as commanded,and RCS jets are activated to augment the aerodynamic surfaces to compensate for insufficient torque.Partial loss of effectiveness and stuck faults are considered in this paper,and observers are designed to detect and identify the faults.Based on the fault identification results,an RCS control allocator using integer linear programming(ILP) techniques is designed to determine the optimal combination of activated RCS jets.By treating the RCS control allocator as a quantization element,closed-loop stability with both continuous and quantized inputs is analyzed.Simulation results verify the effectiveness of the proposed method.
文摘Reaction control system(RCS) is a powerful and efficient actuator for space vehicles attitude control, which is typically characterized as a pulsed unilateral effector only with two states(off/on). Along with inevitable internal uncertainties and external disturbances in practice, this inherent nonlinear character always hinders space vehicles autopilot from pursuing precise tracking performance. Compared to most of pre-existing methodologies that passively suppress the uncertainties and disturbances, a design based on predictive functional control(PFC) and generalized extended state observer(GESO) is firstly proposed for three-axis RCS control system to actively reject that with no requirement for additional fuel consumption. To obtain a high fidelity predictive model on which the performance of PFC greatly depends, the nonlinear coupling multiple-input multiple-output(MIMO) flight dynamics model is parameterized as a state-dependent coefficient form. And based on that, a MIMO PFC algorithm in state space domain for a plant of arbitrary orders is deduced in this paper.The internal uncertainties and external disturbances are lumped as a total disturbance, which is estimated and cancelled timely to further enhance the robustness. The continuous control command synthesised by above controller-rejector tandem is finally modulated by pulse width pulse frequency modulator(PWPF) to on-off signals to meet RCS requirement. The robustness and feasibility of the proposed design are validated by a series of performance comparison simulations with some prominent methods in the presence of significant perturbations and disturbances, as well as measurement noise.
文摘高超声速飞行器再入段初期,所处大气环境空气稀薄,空气舵已无法提供足够力矩来维持姿态稳定,因此就需要反作用控制系统(Reaction Control System,RCS)来提供姿态稳定力矩。针对给定的飞行器RCS八喷管配置方案,基于查表法和脉宽调制,提出了一种能够维持飞行器系统姿态稳定的静态指令分配方法。给出了高超声速飞行器六自由度状态方程,采用一阶滑模控制算法进行姿态稳定控制;基于查表法思想和冲量等效的脉宽调制原理,完成了无故障情况下八喷管指令分配组合表的设计,并根据工程实际对组合表进行容错优化;设计了能够对单推力器发生卡死故障具有容错性的指令分配优化组合表,并采用脉宽调制方法对控制指令进行调制从而获得推力器的开关指令。仿真验证了该指令分配方法能够维持系统姿态稳定,提高控制系统的控制效率,有效解决了八喷管配置以及单喷管卡死故障情况下的指令分配问题。
基金supported by the National Natural Science Foundation of China(11202024)
文摘This paper proposes a novel composite dual-control bycombing the integral sliding mode control (ISMC) method basedon the finite time convergence theory with extended state observer(ESO) for a tracking problem of a missile with tail fins and reactionjetcontrol system (RCS). First, the ISMC method based on finitetime convergence is utilized to design the control law of tail fins andthe pulse control of RCS for the dual-control system, ensuring thesystem with rapid response and high accuracy of tracking. Then,ESO is employed for the estimation of aerodynamic disturbancesinfluenced by the airflow of thruster jets. With the characteristicof high accuracy estimation of ESO, the chattering free trackingperformance of the attack angle command and the robustnessof the control law are achieved. Meanwhile, the stability of thedual-control system is analyzed based on finite time convergencestability theorem and Lyapunov’s theorem. Finally, numerical simulationsdemonstrate the effectiveness of the proposed design.