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181.
Wang Wei Xia Pinqi 《中国航空学报》2007,20(6):501-510
The methodology for adaptive control of helicopter ground resonance with magnetorheological (MR) damper is presented. The adaptive inverse control method is used to control the output damping force of MR damper and the range of the damping force is given. Through the adaptive inverse control, the damping force of MR damper is fit to a desired damping force. With the background of applying MR damper to control of helicopter ground resonance, a model of loss force and an adaptive arithmetic for stabilization of the coupled rotor/fuselage system are presented. The simulation shows that the controller presented in this paper can stabilize the rotor/fuselage coupling system quickly and control the helicopter ground resonance effectively. 相似文献
182.
为满足各型号发动机对冷调试验的设计要求,利用可编程控制器准确的时序控制,在水试状态下考核发动机流量调节器、换向阀、发生器燃料阀的工作协调性。验证调节器转级时发生器点火路和推力室点火路的充填特性,获得了流量调节器和换向阀的工作特性参数。为各型号发动机的深入研究提供了有效的依据。 相似文献
183.
利用CAD软件绘制工程图样更应加强国标意识,采用可编程对话框技术可以实现国家制图标准或其它相关标准的实时服务,从而减少不符国标的图样表达。 相似文献
184.
《中国航空学报》2021,34(4):526-539
This paper proposes a Linkage Learning Genetic Algorithm (LLGA) based on the messy Genetic Algorithm (mGA) to optimize the Min-Max fuel controller performance in Gas Turbine Engine (GTE). For this purpose, a GTE fuel controller Simulink model based on the Min-Max selection strategy is firstly built. Then, the objective function that considers both performance indices (response time and fuel consumption) and penalty items (fluctuation, tracking error, overspeed and acceleration/deceleration) is established to quantify the controller performance. Next, the task to optimize the fuel controller is converted to find the optimization gains combination that could minimize the objective function while satisfying constraints and limitations. In order to reduce the optimization time and to avoid trapping in the local optimums, two kinds of building block detection methods including lower fitness value method and bigger fitness value change method are proposed to determine the most important bits which have more contribution on fitness value of the chromosomes. Then the procedures to apply LLGA in controller gains tuning are specified stepwise and the optimization results in runway condition are depicted subsequently. Finally, the comparison is made between the LLGA and the simple GA in GTE controller optimization to confirm the effectiveness of the proposed approach. The results show that the LLGA method can get better solution than simple GA within the same iterations or optimization time. The extension applications of the LLGA method in other flight conditions and the complete flight mission simulation will be carried out in part II. 相似文献
185.
《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2020,65(1):312-325
Spacecraft relative motion with inter-craft electromagnetic force has distinct advantages, and its invariant shapes that are convenient for formation keeping ensure some potential significant applications. However, the electromagnetic actuators affect both the relative trajectory and attitude motion, complicating related researches on issues of invariant shape design and formation control. In this paper, the formation keeping problem for an invariant three-craft triangular electromagnetic formation is investigated on the basis of a 6-DOF full nonlinear dynamic model. Moreover, a combined control scheme consisting of feed-forward and feed-back control components is proposed to handle the high nonlinearity, strong coupling, model uncertainties and external disturbances. The feed-forward component is obtained through desired invariant shape design which is complicated by the coupling and superposition effects of any two distinct magnetic dipoles, and the feed-back component is developed with a combination of linear feed-back controller by the LQR method and active disturbance rejection by the extended state observer. Finally, the numerical simulation is presented to verify the feasibility and validity of the proposed 6-DOF combined control scheme. 相似文献
186.
187.
A robust constant thrust rendezvous approach under thrust failure is proposed based on the relative motion dynamic model. Firstly, the design problem is cast into a convex optimization problem by introducing a Lyapunov function subject to linear matrix inequalities. Secondly, the robust controllers satisfying the requirements can be designed by solving this optimization problem.Then, a new algorithm of constant thrust fitting is proposed through the impulse compensation and the fuel consumption under the theoretical continuous thrust and the actual constant thrust is calculated and compared by using the method proposed in this paper. Finally, the proposed method having the advantage of saving fuel is proved and the actual constant thrust switch control laws are obtained through the isochronous interpolation method, meanwhile, an illustrative example is provided to show the effectiveness of the proposed control design method. 相似文献
188.
189.
介绍了防滑刹车控制盒在设计中既要考虑可靠性的需求,同时也要满足电磁兼容性的指标,从电磁场与传输线,电涌冲击,屏蔽、滤波和接地,印刷电路板中的电磁兼容性等方面进行了深入的探讨,解决了相关问题. 相似文献
190.