共查询到19条相似文献,搜索用时 125 毫秒
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利用 CFD 计算软件 FLUENT 的二次开发功能和 RNGk-ε湍流模型,建立了无人机投弹流场数值模拟模型和投弹后的弹道仿真模型。运用动网格技术,以固定步长更新投放物与无人机发生相对运动而导致计算域的变化。将整个流场的解与六自由度运动方程的解相结合,分别模拟计算了导弹,炸弹与无人机的分离过程,在气动干扰下,得到了导弹、炸弹的姿态角和位置随时间变化图,并对导弹在有气动干扰下和无干扰情况下得到的弹道数据进行了对比分析。结果表明,气动干扰对导弹、炸弹的纵向运动影响比较严重,而对横侧向运动影响不大。 相似文献
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内埋武器投放分离相容性的风洞投放试验预测与评估 总被引:1,自引:1,他引:0
采用基于运动动力学相似的风洞投放试验对先进战斗机内埋武器投放分离相容性进行预测与评估,给出载机在不同飞行马赫数、攻角、弹舱长深比及舱内武器剩余数量、不同弹射力、折叠翼是否展开下,内埋导弹从载机弹舱投放分离后的运动轨迹和俯仰姿态角变化规律,研究这些因素对内埋导弹投放分离相容性的影响。结果表明:处于超声速飞行状态下(马赫数为1.5)的载机,攻角处于0°、2°、3°时投放内埋导弹后弹体俯仰角处于低头状态,利于攻击载机前下方敌方目标;在给定的初始分离条件下,对于两种不同的弹舱长深比,内埋导弹均能安全分离,但对内埋导弹俯仰方向运动影响较为显著;弹舱内武器剩余数量对内埋导弹分离特性影响较小,导弹能快速地远离载机干扰流场,投放分离后弹体俯仰角一直处于低头状态;随着内埋导弹初始分离速度增大,可使弹体快速地穿过载机的下洗流场,有利于内埋导弹与载机的安全分离;导弹的不同气动布局对内埋导弹分离相容性有一定的影响。 相似文献
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基于飞机桶滚机动规避空空导弹攻击的作战背景,建立了导弹与飞机的空间交会模型。以导弹脱靶量、过载以及舵偏角速率为依据,对桶滚机动不同机动时机、周期下的规避效果以及规避原因进行了仿真分析。研究结果表明,导弹脱靶量与机动时机的关联性较弱,可随着机动周期的增大而减小。当机动周期为 2~3 s时,导弹脱靶量较大,飞机规避效果较好。飞机桶滚机动规避导弹的原因不仅在于导弹交会过程中过载的增大,而且还在于导弹交会过程中舵偏角速率的增大。 相似文献
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悬挂发射系统是飞机与机载武器之间的连接部分,它与机载火控系统配合,承担肴导弹、航空炸弹等悬挂物的运载及投射功能。飞机挂载炸弹、水雷、鱼雷等武器的配套装置称作悬挂投放装置; 相似文献
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机载雷达是导弹攻击机火力控制系统的重要组成部分。它可使飞机在昼夜和复杂气象条件下具有独立作战的能力。导弹是一种远航程的武器,飞机借助雷达能远距离发现、跟踪目标之特性,及早发现、识别目标,占据有利战术位置,发射导弹,对目标进行攻击。 本文根据发射导弹的技术要求,对雷达的主要战术技术指标,雷达在飞机攻击过程中的战术使用,国内雷达的技术性能比较、选型等方面进行讨论。 相似文献
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Pilot uncertainty in aircraft response under automatic flight control has triggered aircraft accidents/incidents in the past. This uncertainty compels a pilot to disengage autopilot and switch to manual control. However, the decision to disengage autopilot and when to do it can be difficult: especially if there is not enough time to monitor the cockpit displays, for instance while countering atmospheric turbulence. Against this background, we proposed the “human as a control module” architecture for harmonizing pilot and autopilot controls. The architecture blends pilot maneuver with autopilot control instead of switching between them when simultaneous inputs are given to the aircraft. By automatically adjusting pilot and autopilot control inputs, the architecture avoids overlaps of both control authorities and helps to circumvent the effect of conflicting actions. This paper applies the architecture to the situations of past aircraft incidents which had been caused by the transfer from autopilot control to pilot maneuver after encountering atmospheric turbulence. The effectiveness of the architecture is evaluated via simulation study for the specific incident examples. Furthermore, this paper extends the architecture with an Extended Kalman Filter (EKF) based observer and evaluates its robustness under errors in wind estimation. 相似文献
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现代飞机越来越复杂的飞行任务对飞机控制系统性能提出了更高要求,而飞机控制系统性能的好坏与飞机自动驾驶仪控制规律设计的优劣关系密切.为此,对某型飞机自动驾驶仪的比例式控制规律进行了分析和设计,仿真研究了控制规律中的速率反馈及位置反馈的作用和选取原则,进而设计出性能良好的飞机角位移自动驾驶仪比例式控制规律.通过大量仿真比较... 相似文献
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提出了一种反舰导弹针对水面机动目标的航向平面控制导引一体化设计方案。建立了航向平面的一体化控制导引模型,然后基于NBF网络切换增益调节和滑模控制的思想进行了控制导引律的设计,为了验证该一体化设计的有效性和正确性,进行了仿真计算。仿真结果表明,针对高机动的水面目标命中精度很高。 相似文献
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We consider the problem of adjusting the gear ratios of the aircraft autopilot without data on bank taking into account wind disturbances caused by atmospheric turbulence. The theory of Markov processes and extremal challenges is used to solve the problem. We present an example of adjusting autopilot gear ratios for the aircraft—autopilot dynamics system under wind disturbances. 相似文献
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This paper presents a new approach to acceleration control of STT (Skid-To-Turn) missiles. In the design and stability analysis of our autopilot, we assume perfect roll-stabilization but consider fully all other nonlinearities of the missile dynamics including the coupling effect due to bank angle. Our autopilot controller consists of a partial-linearizing controller and a dynamic compensator. The partial-linearizing controller along with a time scaled transformation can convert the nonlinear missile dynamics to the so-called normalized system which is completely independent of Mach number and almost independent of air density. The dynamic compensator is designed based on this normalized system. This normalized system greatly simplifies the design process of an autopilot controller regardless of flight conditions. Our autopilot controller can provide fast and exact set-point tracking performance but without the slow-varying conditions on angle of attack and side-slip angle required often in the prior works. 相似文献
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This paper assesses aircraft susceptibility from the first principles, with respect to the threat posed by passively guided infrared homing missiles; with an objective of gaining insight into the comprehensiveness of the relationship between aircraft susceptibility and aircraft infrared signature level. The conventional criterion of aircraft susceptibility assessment based on its lock-on envelop is found to be inadequate, and a new criterion termed here as the Lethal Envelop is presented. The proposed susceptibility assessment criterion is more relevant for coming generation of infrared-guided missiles, because of advancements in the infrared detection technology. A threshold infrared signature level is also proposed as benchmark to be satisfied by all infrared signature suppression systems; if aircraft susceptibility to infrared guided missiles is to be reduced. This analysis is vital for gauging the effectiveness of infrared signature suppression systems. A typical air-to-air combat situation is simulated, and the results that lead to aircraft susceptibility assessment are obtained from this model, which illustrates the comprehensiveness of the redefined aircraft susceptibility assessment approach. 相似文献
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Sang-Yong Lee Ju-Il Lee In-Joong Ha 《IEEE transactions on aerospace and electronic systems》2001,37(4):1236-1252
This paper presents a novel approach to autopilot design for highly maneuvering bank-to-turn (BTT) missiles. In the design and performance analysis of the proposed nonlinear autopilot, all nonlinearities of missile dynamics including the coupling between roll, yaw, and pitch channels as well as the asymmetric structure of missile body are taken into full account. It is shown that through a kind of feedback linearization technique along with a singular perturbation-like technique, the input/output (I/O) dynamic characteristics of pitch, yaw, and roll channels are made linear, decoupled, and independent of flight conditions such as air density and missile velocity. In particular, the proposed autopilot controllers can provide excellent set-point tracking performance for roll and pitch channels while keeping the side-slip angle negligible. The generality and practicality of our approach are demonstrated through mathematical analysis and various simulation results using an ILAAT missile 相似文献
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大空域机动反舰导弹增益调度控制系统设计 总被引:4,自引:3,他引:4
阐明了针对大空域机动反舰导弹飞行空域大、速度变换范围大的特点,采用增益调度的方法设计其控制系统。在理想弹道计算的基础上选取特征点,在每个特征点,将对象简化为一个二阶环节来近似。增益调度表的设计准则是阻尼比,保证导弹在所有特征点的性能要求。特征点的仿真与全弹道仿真均验证了该控制系统的有效性。 相似文献