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1.
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。 相似文献
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《中国航空学报》2021,34(3):225-240
In this paper, the relative sliding motion between the target and the manipulator’s end-effector is considered and characterized as a unilateral contact constraint. A new possible solution is presented to estimate the inertial parameters of a non-cooperative target while the relative sliding motion exists. First, the detailed analysis of the dynamical model is presented, and a parameter-explicit linear time-varying model is obtained. Then, an extended state observer is constructed based on the new model, which can effectively estimate the unknown inertial parameters of the target when relative sliding motion exists. As the modified reactionless controller requires the knowledge of inertial parameters, a hybrid post-capture control scheme is also established based on the switch law between different controllers. The correctness and efficiency of the proposed algorithm are validated by numerical simulation, which proves a potential framework for the non-cooperative target post-capture operation. 相似文献
4.
《中国航空学报》2021,34(5):652-665
There is a strong demand for Planetary Exploration Mobile robots (PEMRs) that have the capability of the traversability, stability, efficiency and high load while tackling the specialized tasks on planet surface. In this paper, an electric parallel wheel-legged hexapod robot which has high-adaption locomotion on the unstructured terrain is presented. Also, the hybrid control framework, which enables robot to stably carry the heavy loads as well as to traverse the uneven terrain by utilizing both legged and wheeled locomotion, is also proposed. Based on this framework, robot controls the multiple DOF leg for performing high-adaption locomotion to negotiate obstacles via Gait Generator (GG). Additionally, by using Whole-Body Control (WBC) of framework, robot has the capability of flexibly accommodating the uneven terrain by Attitude Control (AC) kinematically adjusting the length of legs like an active suspension system, and by Force/torque Balance Control (FBC) equally distributing the Ground Reaction Force (GRF) to maintain a stable body. The simulation and experiment are employed to validate the proposed framework with the physical system in the planetary analog environments. Particularly, to smoothly demonstrate the performance of robot transporting heavy loads, the experiment of carrying 3-person load of about 240 kg is deployed. 相似文献
5.
飞翼飞机易发生刚体短周期模态与机翼低阶弯曲模态耦合所致的体自由度颤振。飞行控制系统对飞机的短周期模态特性影响很大,因此考虑飞行控制系统的闭环体自由度颤振特性值得进一步研究。针对自主设计的颤振模型开发了相应的俯仰姿态保持控制律,综合运用风洞试验和仿真计算开展了相关研究,获得了不同刚体自由边界条件下的开环/闭环体自由度颤振特性,研究了闭环增益对体自由度颤振特性的影响规律,简要分析了影响机理。试验和仿真计算结果共同表明:俯仰姿态保持控制律明显地改变了俯仰模态阻尼的原有走势,闭环后的体自由度颤振特性变化明显。以开环颤振速度为基准,采用较小的比例回路增益KP或较大的微分回路增益KD,飞行控制律能增加飞行器俯仰阻尼,提高体自由度颤振速度,反之飞行控制律将导致颤振速度降低。就本文控制律而言,当KP<0.07或KD>0.2时俯仰姿态保持控制律能起到抑制体自由度颤振的作用。 相似文献
6.
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。 相似文献
7.
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。 相似文献
8.
Yi Wei Qingjun Li Fangnuan Xu 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2021,67(1):393-400
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. 相似文献
9.
M. Naim A. Ali Pacha C. Serief 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2021,67(7):2077-2103
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. 相似文献
10.
针对柔性支撑引起控制力矩陀螺(CMG)框架控制性能下降的问题,建立了柔性支撑条件下控制力矩陀螺的动力学模型,分析了柔性支撑扰动力矩的耦合机理并给出了解析模型.据此,设计了一种积分滑模控制策略,用于提升对CMG框架动力学特性变化和新增扰动力矩的鲁棒性.仿真结果表明,该控制策略相比传统的PID控制具有更好的动态过程和稳态性能,提升了柔性支撑下控制力矩陀螺框架速度的闭环控制性能. 相似文献