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701.
1553B多路传输数据总线接口(MBI)模块,能够实现GJB289—87标准和协议操作规程协议,完成通信系统之间的连接,在通信软件的支持下完成各子系统之间的通信。本文叙述了MBI模块的测试功能,使得MBI模块在航空电子系统的应用中,从功能上和性能上的正确性得以保证。 相似文献
702.
文章简单分析了80960、82380的设计特点和时序特征;介绍了一种80960与82380的接口电路设计方案。 相似文献
703.
笔者所设计的飞机直流发电机电压控制器中采用了SG3524芯片,试制了电路,进行了全电流范围内的试验,调节精度较高,可以取代原有的分立元件式晶体管电压调节器. 相似文献
704.
705.
706.
Backstepping design of missile guidance and control based on adaptive fuzzy sliding mode control 总被引:1,自引:0,他引:1
This paper presents an integrated missile guidance and control law based on adaptive fuzzy sliding mode control. The integrated model is formulated as a block-strict-feedback nonlinear system, in which modeling errors, unmodeled nonlinearities, target maneuvers, etc. are viewed as unknown uncertainties. The adaptive nonlinear control law is designed based on backstepping and sliding mode control techniques. An adaptive fuzzy system is adopted to approximate the coupling nonlinear functions of the system, and for the uncertainties, we utilize an online-adaptive control law to estimate the unknown parameters. The stability analysis of the closed-loop system is also conducted. Simulation results show that, with the application of the adaptive fuzzy sliding mode control, small miss distances and smooth missile trajectories are achieved, and the system is robust against system uncertainties and external disturbances. 相似文献
707.
Dynamic modeling of a hose-drogue aerial refueling system(HDARS) and an integral sliding mode backstepping controller design for the hose whipping phenomenon(HWP) during probe-drogue coupling are studied. Firstly, a dynamic model of the variable-length hose-drogue assembly is built for the sake of exploiting suppression methods for the whipping phenomenon.Based on the lumped parameter method, the hose is modeled by a series of variable-length links connected with frictionless joints. A set of iterative equations of the hose's three-dimensional motion is derived subject to hose reeling in/out, tanker motion, gravity, and aerodynamic loads accounting for the effects of steady wind, atmospheric turbulence, and tanker wake. Secondly,relying on a permanent magnet synchronous motor and high-precision position sensors, a new active control strategy for the HWP on the basis of the relative position between the tanker and the receiver is proposed. Considering the strict-feedback configuration of the permanent magnet synchronous motor, a rotor position control law based on the backstepping method is designed to insure global stability. An integral of the rotor position error and an exponential sliding mode reaching law of the current errors are applied to enhance control accuracy and robustness. Finally,the simulation results show the effectiveness of the proposed model and control laws. 相似文献
708.
Finite-time sliding mode attitude control for a reentry vehicle with blended aerodynamic surfaces and a reaction control system 总被引:1,自引:0,他引:1
This paper proposes a finite-time robust flight controller, targeting for a reentry vehicle with blended aerodynamic surfaces and a reaction control system(RCS). Firstly, a novel finite-time attitude controller is pointed out with the introduction of a nonsingular finite-time sliding mode manifold. The attitude tracking errors are mathematically proved to converge to zero within finite time which can be estimated. In order to improve the performance, a second-order finite-time sliding mode controller is further developed to effectively alleviate chattering without any deterioration of robustness and accuracy. Moreover, an optimization control allocation algorithm, using linear programming and a pulse-width pulse-frequency(PWPF) modulator, is designed to allocate torque commands for all the aerodynamic surface deflections and on–off switching-states of RCS thrusters.Simulations are provided for the reentry vehicle considering uncertain parameters and external disturbances for practical purposes, and the results demonstrate the effectiveness and robustness of the attitude control system. 相似文献
709.
710.
提出了一种反舰导弹滑模非奇异导引律。根据反舰导弹弹道的运动学分析方法,建立了弹目相对运动的数学模型。在非奇异理论的基础上,推导出具有带落角约束的滑模非奇异导引律。通过仿真,表明了该导引律能同时满足脱靶和落角的性能指标,具有优良的鲁棒性,脱靶量更小,精度更高。相比传统的比例导引律,具有更强的实用性和有效性。 相似文献