战斗机电子战系统架构总体设计

战斗机电子战系统提供的态势感知、无源攻击引导、电子对抗和主动隐身等作战能力可以极大提升飞机的生存力和杀伤力。为满足电子战系统越来越高的新质作战能力要求、作战对象快速能力提升、贴近实战的作战样式和作战环境不断变化带来的新要求、适应不同战斗机平台及航电任务系统要求等需求，追求高质量和敏捷开发模式，电子战系统架构必须精心设计。采用系统工程方法，按照能力视图、作战视图、系统视图和技术视图对需求和技术进行了迭代研究，基于灵活数字处理算法支持不同战法、全域综合共用、以快应变和以柔制变等顶层设计思想，从全数字化处理、综合化、可扩展和开放式等多个视角论证了电子战系统架构设计需求，并给出了核心设计要点和方案。战斗机电子战系统架构在大量实践中得到验证，效果良好，能够满足作战使用需求，对下一代战斗机电子系统的研究具有借鉴意义。     

基于改进Q学习的IMA系统重构蓝图生成方法

重构蓝图定义了故障状态下系统软硬件资源的重新配置方案，是实现综合模块化航空电子系统重构容错的关键。提出了一种基于改进Q学习的重构蓝图生成方法，综合考虑负载均衡、重构影响、重构时间、重构降级等多优化目标，并应用模拟退火框架改进探索策略，提高了传统Q学习算法的收敛性能。实验结果表明，与模拟退火算法、差分进化算法、传统Q学习算法相比，本文提出的改进Q学习算法效率更高，所生成重构蓝图质量更高。     

小型电动无人机航程航时估算模型

小型电动无人机通常采用锂电池、无刷电机和螺旋桨组成能源动力系统，飞行过程中锂电池的实际工作电压发生变化，但飞机的总重量不变，其航程航时的估算方法与传统的燃油飞机有所不同。为了准确评估动力系统对飞机设计的影响，建立了以锂电池为动力的电动飞机推进系统模型，通过与实验数据比较，验证了各部分模型的准确性。利用该动力系统模型，对某款小型电动无人机进行了航程和航时估算，结果表明本文的建模方法准确有效，航程航时估算接近实验数据，可作为小型电动无人机设计的重要参考。     

飞机新原理电液自馈能刹车系统设计与优化

当前，传统飞机液压刹车系统普遍采用集中式的机载液压源作为动力，液压能通过能源管路传输到刹车作动器，整个系统零部件数目众多，管路布局复杂，由此带来的管路振动、液压油泄漏等问题突出，限制了飞机刹车系统可靠性和可维护性的提升。近年来，一种飞机新原理电液自馈能刹车系统被提出，将模块化的"自馈能装置"安装在机轮附近，回收机轮着陆时的旋转动能，并将其转换成液压能，用于刹车作动。提出了一种利用波浪曲面进行取能的专用取能机构，设计了自馈能系统紧凑型专用取能机构，研制了高可靠、低能耗、高抗污染的自馈能刹车系统原理样机，完全实现了自馈能，即使飞机失去全部动力也能正常完成刹车功能，使抗污染等级从NAS6级提升到NAS10级，可靠性和可维护性优于传统液压刹车。     

Orbit-attitude-vibration coupled dynamics of tethered solar power satellite

A new orbit-attitude-vibration coupled dynamic model of the tethered solar power satellite (Tethered SPS) is established based on absolute nodal coordinate formulation. The Hamilton’s equation of the system is derived by introducing generalized momentum through Legendre transformation. The correctness of the proposed model is verified by an example. The dynamic characteristics of the Tethered SPS are studied using the symplectic Runge-Kutta method. Simulation results show that the orbital radius and the total energy of the system are well preserved. The attitude of the system is unstable when the mass of the bus system is small. However, the attitude stability is dependent on some other parameters of the system, which requires further studies. It is also found that the average tether force/deformation can be roughly estimated by simplifying the solar panel as a particle. The proposed model can be used to study the orbit-attitude-vibration coupled dynamics and control problems.     

基于Kalman滤波的空天飞行器再入制导算法

针对空天飞行器应用传统数值预测校正再入制导算法实时性不佳的问题，提出一种基于Kalman滤波的预测校正制导算法。该算法采取四阶多项式拟合速度-高度飞行剖面，利用Kalman滤波估计选定的速度点对应的高度，得到满足再入走廊及航程要求的拟合系数。在此基础上，减少一个终端约束，增加一个待估计剖面参数，可实现对再入过程飞行时间的调节。研究发现，再入过程中通过在线辨识修正不确定性参数能够提高制导指令的适应性；飞行末段利用跟踪参考剖面制导可有效避免飞行速度与终端速度接近时发生拟合系数求解发散的问题。多组不同再入条件下的算例仿真结果表明，基于Kalman滤波的空天飞行器再入制导算法实时性好，制导精度高，能够实现飞行时间可控，具有较强的鲁棒性和工程应用潜力。     

Aerodynamic design of tractor propeller for high-performance distributed electric propulsion aircraft

Aiming to maximize the aerodynamic performance of the Distributed Electric Propulsion (DEP) aircraft, a hybrid design framework which focuses on the aerodynamic performance of the propeller/wing integration has been developed and validated numerically. Variable-fidelity modelling for propeller aerodynamics has been used to achieve computational efficiency with reasonable accuracy. By optimizing the aerodynamic loading distributions on the tractor propeller disk, the induced slipstream is redistributed into a form that is beneficial for the wing downstream, based on which the propeller blade geometry is generated through a rapid inversed design procedure. As compared with the Minimum Induced Loss (MIL) propeller at a specified thrust level, significant improvements of both the lift-to-drag ratio of the wing and the propeller/wing integrated aerodynamic efficiency is achieved, which shows great promise to deliver aerodynamic benefits for the wing within the propeller slipstream without any additional devices.     

A novel satellite image encryption algorithm based on hyperchaotic systems and Josephus problem

With the rapid growth of the number of Earth observation satellite (EOS) supporting critical applications, it is required to improve the security techniques to protect the sensitive data and images during the transmission between the satellites and the ground stations. This paper introduces a new satellite image encryption algorithm based on the Linear Feedback Shift Register (LFSR) generator, SHA 512 hash function, hyperchaotic systems, and Josephus problem. LFSR generates a matrix that is used to construct the 512-bits value of the hash function. These bits are used to set the initial values and parameters of the proposed encryption algorithm. Firstly, the six dimensions (6-D) hyperchaotic system is divided into three parts, where every two equations are considered as one part. Secondly, the 1-D hyperchaotic logistic-tent system is considered as the controller to select one part. The selected part is used to generate a matrix that is XORed with the original image. Thirdly, the scrambling operation by Josephus sequences is applied to the output of the previous step by scrambling the rows and the columns according to the selected part to produce the pre-encrypted image. Finally, if the number of iterations is less than the required number which is considered as a parameter of the secret key, the previous operations will be repeated in the pre-encrypted image; otherwise, the pre-encrypted image is considered as the final cipher image. Experimental and analyses results show that the proposed algorithm has good performance in terms of high level of security, large enough key-space, tolerance to Single Event Upsets (SEU) as well as low time complexity.     

某型惯性导航系统典型53#故障的排除及解析

某型惯性导航系统在飞机上时有故障发生,造成导航系统无法正常使用,其中较为突出的是惯导报53#环境温控故障。为降低该惯导在飞机上的故障率,通过研究环境温控回路的工作原理,解析其故障机理,并以几起典型53#故障的排除为例深入分析,提出有效的预防措施,以延伸修理深度,提高产品修理质量。