薄壁密封舱大承载胶接结构设计

载人航天器大型化、轻量化的特点对结构效率提出了更高的要求,文章提出一种薄壁密封舱大承载胶接结构设计方法,通过采取胶接区域变厚度设计、通气孔分布式设计、打磨工艺设计和抽真空加压设计等针对性改进措施,有效解决了"浴盆效应"、支座与舱壁的刚度匹配、舱壁局部表面处理以及胶接加压等问题。仿真分析和试验表明:支座在胶层剥离前可承受约12 000N的剪力,胶接性能得到明显提高,此方法可用于密封舱舱内结构设计。     

载人航天器防火安全设计

防火安全是载人航天器总体设计所关注的重点项目之一。文章按照火灾发生三要素,结合以往密封舱防火安全设计经验,从密封舱内可燃物控制、舱内氧浓度控制、防止点火源形成、防止火灾传播、密封舱烟火监测和密封舱灭火6个方面对载人航天器防火安全设计方法进行了归纳总结。该研究可为我国后续载人航天器密封舱防火设计提供重要依据,确保载人航天器任务期间的安全可靠性。     

载人航天器密封舱内结露的原因及对策

密封舱内结露威胁在轨航天员的安全和载人航天器的性能。文章探讨了载人航天器密封舱结露的产生原因,以及防止和减小结露的设计方法,可供类似的载人航天项目进行热控设计时参考。     

载人航天器密封系统漏率设计方法

载人航天器密封舱为航天员提供在轨生活、工作的环境,对密封舱及其环控生保系统、热控制系统、推进控制系统等中各管路的密封性能有严格要求。文章提出了一种漏率设计方法,建立了相应的漏率检测系统,并依据该方法制定了密封舱体和各管路的漏率设计和指标分配的流程。本流程可用作载人航天器舱体密封系统、管路密封系统的漏率设计,对保证载人航天器在轨安全可靠运行有重要参考价值。     

载人航天器密封舱地面微生物控制与检测

研究载人航天器密封舱微生物控制技术的目的是指导后续长期驻留阶段密封舱微生物的控制工作。文章以某中短期驻留载人航天器为例,分析了航天器发射前地面研制阶段微生物控制的关键因素,提出了控制方法,并对舱内微生物控制情况进行了实际检测。测试结果表明微生物控制水平满足驻留要求,控制措施有效。     

载人航天器密封舱噪声控制与试验

载人航天器密封舱为航天员工作和生活的场所,需对航天员工作区和睡眠区进行噪声控制。文章以某中期驻留载人航天器为例,对其密封舱内的主要噪声源进行识别,并从吸声、隔声、消声、减振4个方面针对主要噪声源进行噪声控制。根据航天器实际噪声源和控制措施,构建了噪声计算模型,通过仿真分析获取了舱体内声压级水平分布,并对舱内噪声分布进行实际测试。仿真结果和测试结果表明噪声控制方案满足指标要求,噪声源识别准确,控制措施有效。     

一种基于非线性回归的载人航天器密封舱内在轨噪声分析方法

文章提出一种载人航天器密封舱内噪声非线性回归通用分析方法,可基于地面噪声试验测得的数量较多的数据样本和在轨噪声测试获取的少量数据样本,建立密封舱内位置–在轨噪声的数学模型。经验证该模型能够较为准确地拟合密封舱内在轨噪声水平,从而为开展载人航天器的降噪设计、优化噪声仿真模型和验证降噪措施效果提供数据支持。     

载人航天器密封舱内管路设备维修设计与验证

载人航天器密封舱内配置大量的气、液管路设备,实现管路设备的在轨维修,对于提高长期在轨飞行载人航天器的安全性及使用寿命具有重要意义。文章对某载人航天器再生生保管路设备在轨维修性进行了设计,经地面充分验证后,航天员在轨完成了管路设备维修操作,结果表明本文提出的管路设备在轨维修设计正确、有效,可为载人航天器其他在轨维修设计提供参考。     

铝合金新材料在载人密封舱主结构中的应用研究进展

文章简述了铝合金新材料在载人密封舱主结构中的应用研究进展,总结了传统航天用铝镁系铝合金的特点,在相关实验研究的基础上,通过对比分析指出,新型5B70铝镁钪合金具有优良的综合性能,将是我国未来载人密封舱主结构升级换代的最佳备选材料。结合当今载人航天器的发展需要,剖析了传统铝合金材料在未来载人航天器升级换代这过程中亟待解决的难题和将要面临的挑战。     

载人航天器密封舱内生物剂量三维仿真技术

对载人航天器密封舱内航天员遭受的生物剂量进行研究分析,可为乘员辐射防护设计和工程实施提供依据。文章将基于一维深度-剂量计算、结合扇区射线法的三维辐射仿真技术运用于载人航天器总体设计中,以某中期驻留载人航天器为例,构建生物剂量仿真分析模型。计算实例分析表明,三维剂量仿真结果可有效指导乘员辐射防护优化设计,对后续长期载人飞行中的航天员辐射安全设计具有较强的实用性。     

以RBCC为动力的巡航飞行器有效载荷质量敏感性分析

基于飞行轨迹及质量分析数学模型,对以RBCC为动力的巡航飞行器有效载荷的敏感性进行了分析,主要考虑了发动机比冲、发射马赫数、发射高度、模态转换点(转换马赫数)及惰性质量系数等对有效载荷质量的影响。分析结果表明,提高发射马赫数和发射高度、增加发动机比冲、降低模态转换马赫数及飞行器惰性质量系数有利于提高巡航飞行器的有效载荷质量。其中有效载荷质量对惰性质量系数最敏感,当惰性质量系数分别减小7.3%和增大7.3%时,有效载荷质量的增大量和减小量将分别达到58%和103.7%。     

基于微振动隔离技术的平台载荷一体化设计

针对大口径高分辨率相机对卫星平台结构、安装包络、振动环境等方面的要求,提出了一种基于微振动隔离技术的平台载荷一体化设计与分析方法。通过在卫星平台与载荷安装基板之间的一体化结构中增加柔性连接单元,利用系统刚度和能量耦合的原理对一体化结构平台的系统性能进行设计和仿真分析,并在此基础上,开展了平台载荷一体化结构地面模拟试验研究。结果表明：文章提出的基于微振动隔离技术的平台载荷一体化设计在满足载荷安装要求的同时,还能够将卫星平台传递至载荷基板的振动响应衰减80%以上,从而有效地确保载荷的主要性能。     

LISA — a study of the ESA cornerstone mission for observing gravitational waves

The primary objective of the Laser Interferometer Space Antenna (LISA) mission is to detect and observe gravitational waves from massive black holes and galactic binaries in the frequency range 10⁻⁴ to 10⁻¹ Hz. This low-frequency range is inaccessible to ground-based interferometers because of the unshieldable background of local gravitational noise and because ground-based interferometers are limited in length to a few km. LISA is an ESA cornerstone mission and recently had a system study (Ref. 1) carried out by a consortium led by Astrium, which confirmed the basic configuration for the payload with only minor changes, and provided detailed concepts for the spacecraft and mission design. The study confirmed the need for a drag-free technology demonstration mission to develop the inertial sensors for LISA, before embarking on the build of the flight sensors. With a technology demonstration flight in 2005, it would be possible to carry out LISA as a joint ESA-NASA mission with a launch by 2010 subject to the funding programmatics. The baseline for LISA is three disc-like spacecraft each of which consist of a science module which carries the laser interferometer payload (two in each science module) and a propulsion module containing an ion drive and the hydrazine thrusters of the AOCS. The propulsion module is used for the transfer from earth escape trajectory provided by the Delta II launch to the operational orbit. Once there the propulsion module is jettisoned to reduce disturbances on the payload. Detailed analysis of thermal and gravitational disturbances, a model of the drag-free control and of the interferometer operation confirm that the strain sensitivity of the interferometer will be achieved.     

Multiobjective optimization applied to structural sizing of low cost university-class microsatellite projects

In recent years, there has been continuing interest in the participation of university research groups in space technology studies by means of their own microsatellites. The involvement in such projects has some inherent challenges, such as limited budget and facilities. Also, due to the fact that the main objective of these projects is for educational purposes, usually there are uncertainties regarding their in orbit mission and scientific payloads at the early phases of the project. On the other hand, there are predetermined limitations for their mass and volume budgets owing to the fact that most of them are launched as an auxiliary payload in which the launch cost is reduced considerably. The satellite structure subsystem is the one which is most affected by the launcher constraints. This can affect different aspects, including dimensions, strength and frequency requirements. In this paper, the main focus is on developing a structural design sizing tool containing not only the primary structures properties as variables but also the system level variables such as payload mass budget and satellite total mass and dimensions. This approach enables the design team to obtain better insight into the design in an extended design envelope. The structural design sizing tool is based on analytical structural design formulas and appropriate assumptions including both static and dynamic models of the satellite. Finally, a Genetic Algorithm (GA) multiobjective optimization is applied to the design space. The result is a Pareto-optimal based on two objectives, minimum satellite total mass and maximum payload mass budget, which gives a useful insight to the design team at the early phases of the design.     

微小卫星解锁分离装置主结构设计分析及优化

文章介绍了某小卫星包带式星箭解锁分离装置初样产品的设计方案,建立了该装置的有限元模型,并通过轴向压缩静力试验验证了该模型的有效性。卫星用质心处的集中质量点代替,对解锁分离装置进行了模态与静力分析,验证了其主结构设计的合理性,同时还具有较高的安全裕度和可优化空间。以卫星总质量为目标函数,解锁分离装置主结构各构件的壁厚为设计变量,并以初样产品的横向、轴向和扭转的基频以及其主结构强度满足设计要求为约束条件,进行了灵敏度分析和优化设计,优化后的解锁分离装置总质量减少了1.5 kg。     

ERDSAT,a satellite concept for Earth observations with combined optical and microwave payload

The concept of a European remote sensing satellite (ERDSAT) launched by ARIANE is characterized by a model payload, consisting of a synthetic aperture radar (SAR) and an optical multispectral scanner with 9 channels, for land applications or coastal zone missions. The mission goal of ERDSAT is based on European user requrements where a strong need for optical and microwave sensor operation on board the same satellite in a simultaneous or sequential mode is expressed. A data collection system is included. The proposed spacecraft is three-axes-stabilized and has a Sun-synchronous, near polar circular orbit with 750 km altitude. The selected configuration separates payload module and bus module. A thermostable carbon fibre grating structure is the central framework of the satellite. Each major subsystem is housed in a separate compartment and can be integrated and tested individually. First mass estimates resulted in 450 kg for the payload and 880 kg for the bus. The maximum power needed is 1750 W (for 6 min three times a day), which will be provided by a 1330 W solar array and two batteries. A “low cost” model philosophy is defined; the time schedule envisages a program start in late 1980 and a launch possibility end of 1985.     

The transcost-model for launch vehicle cost estimation and its application to future systems analysis

The first part of the paper describes the structure of the analytical cost estimation model (1982 edition) for launch vehicle development, fabrication and launch operations cost. Especially the new approach for a cost assessment of operations cost including refurbishment (in case of reusable vehicles), direct and indirect operations is presented for discussion and subsequent improvements by introduction of more reference values. The model uses the Man-Year (MY) as cost unit which is independent from inflation and currency exchange rate changes.

The second part of the paper deals with its application to future systems analysis and cost comparison with the example of a potential future European launcher (Post-Ariane-4) with 15 tons LEO payload capability: ten different two-stage launch vehicle concepts (expendable, semi-reusable and fully reusable) with storable and cryogenic propellants are analysed with respect to development cost and cost per launch.

The key problem for a future European launch vehicle is the optimum solution between the (limited) development effort and the desired minimum launch cost. More advanced (partially) reusable systems could provide an essential reduction in cost per launch, require, however, a higher development effort.

In such a case an analytical cost model based on realistic reference data can provide important data for the vehicle concept selection process.     

多格式载荷数据处理与管理平台的设计和实现

为了解决现有航天器载荷数据处理软件灵活度差、处理效率低的问题,设计了一种基于多级解包预处理策略以及并行处理调度算法的多格式载荷数据处理与管理平台。通过在某卫星的载荷试验数据处理与存储管理任务中的应用,验证了该平台设计的可行性和有效性。研究结果可为航天器多种格式的载荷数据并行处理与统一管理提供参考。     

某型卫星有效载荷支架振动抑制

某型号卫星的有效载荷支架结构在验收级振动试验时振动超标。在对结构不做大的修改的前提下，采用约束阻尼层用对原结构进行处理。对不同的约束阻尼层方案采用有限元方法进行计算，综合考虑各种影响因素，如阻尼比和附加质量等，得到合理的约束阻尼减振方案，并在结构星上进行试验，确定最终实施方案。实施方案后，正样星在0．1g振动条件下，最大振动幅值下降了22．3％，保证了卫星的顺利发射。该卫星已经成功发射，并且在轨运行正常。该问题的成功解决和解决问题的方法与过程为今后解决类似问题提供了经验。     

嫦娥五号轻量化高精度上升器结构设计

针对嫦娥五号上升器结构面临的轻量化设计要求严苛、有效载荷接口精度要求极高和有效载荷指向变化预示精度要求很高的难题,提出至顶向下的结构轻量化设计方法,使得上升器结构自重降低到整器重量的6.2%(47.758 kg);建立压紧和精度保持功能分离、双坐标系分级实现高精度的结构设计方法,实现相关有效载荷的结构安装接口精度达到400 mm×400 mm区域平面度小于或者等于0.05 mm;探索出综合了有效载荷自身和安装结构耦合效应的有效载荷在轨指向变化预示方法,实现准确、高效、快速地对有效载荷指向变化进行角秒级高精度评估。这些方法支持完成中国月面无人自动采样返回任务,并最终促进中国航天器结构技术的发展。