参数不确定SGCMG系统的鲁棒操纵律设计

在单框架控制力矩陀螺(SGCMG)系统操纵律的设计中，如果考虑框架伺服特性，往往假设系统的物理参数是确切已知的。为消除参数的不确定性对操纵性能的影响，设计了一种鲁棒操纵律。该操纵律仅采用系统物理参数的预估值，根据航天器姿态控制给出的角动量(或力矩)指令，可直接计算出每个框架驱动系统所需的控制力矩。由于操纵律没有算法奇异，在SGCMG系统不出现运动奇异的情况下，可使操纵误差指数收敛至零。同时，该操纵律对系统参数变化具有良好的鲁棒性。且形式简单．易于实现。对应用在航天器上的某4-SGCMG系统的仿真结果表明，上述操纵律是可行的。     

星冕仪制冷机黏弹性隔振平台的非线性振动建模分析

中国空间站巡天望远镜（CSST）中的星冕仪模块能够实现系外行星直接成像,然而在轨运行期间其运动模块会产生微振动扰动而导致图像质量下降。文章针对航天载荷常用隔振系统进行非线性建模分析,针对黏弹性材料的Kelvin-Voigt模型进行非线性扩展,通过三阶谐波平衡法对本构方程求解。以微分形式建立了非线性Kelvin-Voigt模型的振动运动方程,对类似的设计假设以及工程应用提供了理论依据;模型分析结果表明,扩展后的非线性实体模型有效补充了非线弹性的微振动隔振系统设计理论,有助于提高工程设计的数据精度。     

磁悬浮控制的主动式隔振平台研究

磁悬浮隔振是一种新型的电磁力控制主动式隔振技术，在介绍磁悬浮隔振平台的基本原理基础上，分析了磁悬浮隔振的机理和特性，推导了其动态模型，论述了磁悬浮隔振控制策略，进行了隔振效果的计算机仿真，并以一个磁悬浮隔振试验装置为对象，进行了试验和测试。     

星箭界面整星隔振设计及减振效果验证

星箭界面减振设计对改善卫星发射时的动力学环境具有重要意义。文章设计串联式磁流变阻尼隔振平台和并联式黏滞阻尼隔振平台,并对这2种隔振平台基于某中型卫星模型开展整星系统级隔振性能的工程试验研究,通过减振特性对比分析评估它们的减振效果。结果显示：串联式磁流变阻尼隔振平台3方向减振效果均较好,质量控制满足设计要求,但会改变系统固有频率;并联式黏滞阻尼隔振平台对系统结构质量和固有频率的影响均较小,x向减振效果较好,但y向、z向减振效果不理想,须进一步优化系统参数。研究结果可为整星隔振的实际工程应用提供依据。     

航天器精密设备隔振问题的功率流最优化研究

空间开发及探测活动使航天器及其所携带的精密设备置于非常复杂的力学环境之下，为此，隔振技术在航天技术领域得到了广泛的应用。本文针对航天器上典型隔振问题，建立了隔振系统振动功率流响应特性分析模型；并以减振器安装界面的振动功率流为综合控制量，以减振器的特征参数为优化变量，分别建立了单目标和多目标加权的优化模型；最后，以一多自由度集中参数模型为例，研究了该隔振系统振动功率流响应特性及减振器系数的优化问题，计算结果不仅验证了模型推导的正确性，并且表明，功率流分析方法能够独到地预示隔振系统振动能量的分布特性，基于振动功率流的减振器动力特性的参数优化设计可以有效地改善隔振效果，具有一定的工程意义。     

Singularity analysis and steering control laws for adaptive-skew pyramid-type control moment gyros

In contrast to past studies that have treated the skew angle as fixed in pyramid-type control moment gyro (CMG) systems, this paper treats the adaptive-skew pyramid-type CMG (ASCMG) system, in which the skew angle is one of the control variables for generating torques. The singular surfaces of the fixed-skew CMG are analyzed and visualized to illustrate how they depend on the skew angle, and the singular surfaces of the ASCMGs are also analyzed and visualized from a viewpoint of null motion for not only the gimbal angle but also the skew angle. The steering control laws are presented, and we numerically study their effectiveness for the reduction of settling time as compared to the fixed-skew pyramid-type CMGs.     

典型细长体结构的两点激励振动试验设计

在传统的细长体结构的振动试验中,通常采用单一振动台,通过扩展台面连接、多点平均控制的方式开展试验,可能造成结构不同部位的过试验或欠试验;而采用多个振动台协同开展振动试验可以模拟细长体结构的多点载荷激励,可提高试验模拟的置信度。文章通过某典型细长体结构,分析了传统单点激励振动试验的问题,对该结构两点激励振动试验方案、夹具、控制等的设计情况进行了介绍,并给出了实际试验结果。研究结果可为开展类似细长体结构的两点激励振动试验提供参考。     

Digital control algorithms for multi-degree-of-freedom microgravity isolation systems

Two general methodologies have been developed to design digital controllers for multi-degree-of-freedom microgravity isolation systems such that the desired transmissibility matrix is achieved. The absolute accelerations and relative displacements are used as feedback signals. Absolute acceleration signals are used to provide proportional damping in the system whereas relative displacement signals are used to achieve the desired transmissibility. In the first method, the closed-form expression of the controller transfer function metrix for the relative displacement feedback is obtained directly in the Z-domain. The controller transfer function matrix is first obtained in the S-domain and then discretized in the second method. The discrete-time controller transfer function matrices and numerical results are presented for a three-degree-of-freedom system with attractive electromagnetic actuators.     

液体火箭发动机协同设计平台关键技术

针对液体火箭发动机协同设计工程实际需求,围绕研制数据高效流转与协同,面向产品全生命周期跨地域、跨专业特点,提出了协同设计平台框架。针对协同平台中的5项关键技术,给出了相应解决途径。基于PLM系统构建协同环境,建立统一编码,整合研制过程中的标准件、原材料等共性基础数据;通过基于MBD的三维结构设计,采用MBSE理念,以模型为载体升级发动机设计流程;采用线上IPT模式提升产品设计效率,同时实现全过程数据记录知识累积。采用BOM结构组织和展示不同设计阶段形成的数据;基于Hadoop平台分布式数据存储模式,实现结构化和非结构化数据综合管理。通过工程实践验证表明,构建的协同平台实现了基于数字化模型的设计工艺定制化协同,科研生产全过程的信息整合和多维度监控,促进了业务流程持续优化和研制效率不断提升,支撑发动机研制模式的转型升级。     

基于联合仿真技术的虚拟振动试验平台建设

对电动振动台机电耦合系统进行辨识,通过Amesim软件建立了电动振动台的机电耦合模型,在Virtual.lab软件中建立了振动台与试验件的刚柔耦合模型,借助Matlab/Simulink软件建立了振动台的控制系统,最终基于联合仿真技术建立起了闭环虚拟振动台的正弦扫描振动试验平台。通过算例研究,表明所建立的虚拟振动试验平台能够很好地实现对试验件的正弦扫描振动试验,并能够实现仿真结果在Virtual.lab中的可视化。     

三轴振动试验系统工作平台的谐振频率分析

为验证并提高三轴振动试验系统工作平台的谐振频率,进而提高系统的工作频率范围,文章采用有限元软件对平台在自由状态下的模态进行仿真。比较仿真结果与三轴振动试验结果可以看出,对角和对边弯曲频率偏差较小。该结果可为后续设计工作提供相对精确的计算指导。     

质量矩复合控制拦截器一体化制导控制方法

在建立质量矩复合控制拦截器制导控制一体化数学模型的基础上,利用微分几何策略对一体化制导控制系统进行了设计,给出了发动机期望控制力矩和滑块期望位置指令,并采用极点配置方法对反馈控制系数进行了设计。为保证系统具有能控性,对滑块质量和发动机稳态推力参数进行了设计。仿真结果表明,该方法能实现拦截器末段的制导控制,同时能降低对滑块执行机构的功率要求。     

A practical small satellite variable-speed control moment gyroscope for combined energy storage and attitude control

A recent effort to develop single-gimbal variable-speed control moment gyroscopes (VSCMGs) for a combined energy storage and attitude control subsystem (ESACS) on small satellites has culminated in laboratory validation of the concept. A single actuator prototype comprised of a cutting-edge Carbon Fiber rotor and COTS motor/generator components has been developed, balanced, bench tested, and integrated onto a spherical air-bearing structure. This structure is used to demonstrate the primary capability of a VSCMG to act as a dynamo whilst simultaneously changing a spacecraft's orientation in a controlled fashion. As originally predicted, the actuator's flywheel spins up when energy is supplied (supported via a direct energy transfer power architecture), then spins down when the energy source is removed, porting the energy released to run a resistive load.The work presented gives an overview of the governing principles of the technology, addresses the underlying mission and design requirements, and presents the prototype design. Then, effectiveness of the prototype integrated on a three-axis test article is presented along with its associated test data. Finally, discussion of these results and identification of future research concludes the work. The benefits of this technology for future space missions are that system consolidation permits mass reduction, higher instantaneous peak power is available as compared to conventional secondary battery systems, state-of-charge measurement is readily available from wheel speed feedback, and torque amplification through gimballing permits efficient actuator control. The technology demonstrated is exciting and leaves the door open for future development via inclusion of magnetic levitation.     

Design,modeling and control for a stratospheric telecommunication platform

The stratospheric airship provides a unique and promising platform for broad band telecommunication relay missions, which combine the advantages of both terrestrial and satellite communication. In this paper, the conceptual design, dynamics modeling and attitude control of the stratospheric telecommunication platform are presented. First, the stratospheric telecommunication platform is introduced, including conceptual design, configuration, energy sources, propeller and payload. Second, dynamics model of the platform is derived form the Newton–Euler formulation and the station-keeping attitude control problem is formulated. Then, the adaptive fuzzy sliding mode control scheme is proposed to develop the attitude-tracking control system, with a particular focus on parametric uncertainties and external disturbances. Finally, simulation results verify the effectiveness and robustness of the proposed control scheme. The proposed conceptual design and control scheme provide a promising approach for telecommunication relay missions using the stratospheric station-keeping airship.     

电子装备试验大数据分析服务平台架构设计

结合大数据技术和电子装备试验特点,提出电子装备试验大数据基本概念,在数据、用户、能力等需求分析的基础上,设计灵活、可扩展的电子装备试验大数据分析服务平台架构,并探讨电子装备试验大数据分析服务平台在试验机构内外的应用模式.提出的平台架构可以为相关领域数据中心建设提供支持,为试验数据增值增效提供支持.     

质量矩导弹的神经网络及自适应非线性控制

本文对质量矩控制导弹的动力学方程简化和控制系统的设计进行了研究。详细阐述了所提出的控制方法，介绍了径向基单隐层神经网络进行误差补偿的算法原理，用Lyapunov理论证明了所采用方法的稳定性。在给出了质量矩导弹的六自由度动力学方程和简化后的方程后，用所提出的方法设计控制系统。通过仿真分析，得出了本文所提出的方法具有较好的误差补偿能力的结论。     

再入飞行器的RCS控制系统设计

针对再入飞行器初始再入段的发动机反作用控制系统(RCS)控制精度问题,提出了一种新型发动机控制方法。首先,将飞行器模型分为慢回路和快回路分别进行控制器设计,采用非线性干扰观测器(DOB)来获取不确定项的估计值,并使用反演法及滑模控制方法设计了飞行器的慢回路和快回路控制律;其次,采用线性规划方法来获取最优RCS指令分配方案;在此基础上,对传统PWPF调制器进行改进,提出了积分补偿型PWPF调制器(IPWPF),采用描述函数法证明了该IPWPF的调制稳定性;最后,通过仿真验证了该方法相比于传统的控制方法具有较高的控制精度。     

基于自适应模糊观测器的挠性航天器主动振动抑制方法研究

针对一类挠性航天器的柔性附件主动振动抑制问题,提出了自适应模糊观测器及变结构反馈控制律的设计方法.所设计的观测器是一种非线性广义Luenberger自适应观测器,采用模糊系统逼近非线性函数,并不需要引入航天器本体姿态信息,结构简单.最后通过数字仿真验证了该方法的有效性.     

Magnetic dipole moment estimation and compensation for an accurate attitude control in nano-satellite missions

Nano-satellites provide space access to broader range of satellite developers and attract interests as an application of the space developments. These days several new nano-satellite missions are proposed with sophisticated objectives such as remote-sensing and observation of astronomical objects. In these advanced missions, some nano-satellites must meet strict attitude requirements for obtaining scientific data or images. For LEO nano-satellite, a magnetic attitude disturbance dominates over other environmental disturbances as a result of small moment of inertia, and this effect should be cancelled for a precise attitude control. This research focuses on how to cancel the magnetic disturbance in orbit. This paper presents a unique method to estimate and compensate the residual magnetic moment, which interacts with the geomagnetic field and causes the magnetic disturbance. An extended Kalman filter is used to estimate the magnetic disturbance. For more practical considerations of the magnetic disturbance compensation, this method has been examined in the PRISM (Pico-satellite for Remote-sensing and Innovative Space Missions). This method will be also used for a nano-astrometry satellite mission. This paper concludes that use of the magnetic disturbance estimation and compensation are useful for nano-satellites missions which require a high accurate attitude control.     

Singularity avoidance of control moment gyros by one-step ahead singularity index

A steering law of control moment gyros for spacecraft attitude control by using one-step ahead singularity index is addressed in this paper. In some recent studies, the null motion approaches or singularity robustness steering laws have been extensively investigated to avoid singular configurations for a control momentum gyro (CMG) cluster. As a novel approach different from them, the proposed approach is based on optimization technique by minimizing the one-step ahead singularity index. Modified approaches are also presented in this paper. The proposed one-step prediction method ultimately gives an optimized solution of gimbal rates with advanced ability to avoid a singularity. A singularity index for reliable computation of a gradient vector is also introduced. Finally, performance of the proposed algorithm is demonstrated by numerical simulations.