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91.
92.
GA-Based Model Predictive Control of Semi-Active Landing Gear 总被引:1,自引:1,他引:0
WU Dong-su GU Hong-bin LIU Hui 《中国航空学报》2007,20(1):47-54
Semi-active landing gear can provide good performance of both landing impact and taxi situation, and has the ability for adapting to various ground conditions and operational conditions. A kind of Nonlinear Model Predictive Control algorithm (NMPC) for semi-active landing gears is developed in this paper. The NMPC algorithm uses Genetic Algorithm (GA) as the optimization technique and chooses damping performance of landing gear at touch down to be the optimization object. The valve's rate and magnitude limitations are also considered in the controller's design. A simulation model is built for the semi-active landing gear's damping process at touchdown. Drop tests are carried out on an experimental passive landing gear systerm to validate the parameters of the simulation model. The result of numerical simulation shows that the isolation of impact load at touchdown can be significantly improved compared to other control algorithms. The strongly nonlinear dynamics of semi-active landing gear coupled with control valve's rate and magnitude limitations are handled well with the proposed controller. 相似文献
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94.
Phased-Mission Systems(PMS) are widely applied in aerospace, telecommunication and intelligent systems for multiple, consecutive and non-overlapping phases of missions. The phasedependent stresses and system structure cause some difficulties to the reliability analysis of PMSs.In this paper, we analyze the physical isolation effects on the degradation speeds and across-phase damage accumulations of failure mechanisms. And, some corresponding reliability and unreliability formulas are derived. Be... 相似文献
95.
96.
基于HCNR201的信号测量电路的研究 总被引:1,自引:0,他引:1
现代测控系统常用弱电信号控制强电,电气隔离至关重要。针对目前电气隔离器件状况,提出基于高精度线性光耦HCNR201的电压、电流测量电路。实验结果表明:电路稳定性好、线性度高。 相似文献
97.
通过对两起典型的A320飞机故障进行分析研究,探索并总结在航线维护工作中除按照TSM手册进行排故外,如何方便快捷地找出故障源,排除故障并保障航班安全正点。 相似文献
98.
虚拟专用Intranet安全研究 总被引:2,自引:0,他引:2
介绍了一种实现虚拟专用Intranet的安全策略--基于身份的可靠加载(SIBL),另外阐述了如何保证SIBL网络的完整性的措施和策略。 相似文献
99.
工业微机控制系统小信号采集的抗干扰措施 总被引:1,自引:0,他引:1
本文简述了工业微机控制系统小信号采集过程中常见的干扰来源,并介绍了一种简便,有效的抗干扰措施。 相似文献
100.
《中国航空学报》2016,(1):238-247
As powerful torque amplification actuators, control moment gyros (CMGs) are often used in the attitude control of many state-of-the-art high resolution satellites. However, the distur-bance generated by the CMGs can not only reduce the attitude stability of a satellite but also dete-riorate the performance of optic payloads. Currently, CMG vibration isolators are widely used to target this problem. The isolators can affect the singularity of the CMG system as they are placed between the CMGs and the satellite bus and provide additional freedoms to the CMG system due to their flexibility. The formulation of the output torque of a CMG is studied first considering the dynamic imbalance of its spin rotor and then the deformation angle as a result of the isolator’s flex-ibility is calculated. With the additional freedoms, the influence of isolator on the singularity problem is studied and a new steering logic to escape from the singular states is proposed. 相似文献