【摘 要】
：
In this paper,four novel evaluation indices and corresponding hierarchical optimization strategies are proposed for a deployable solar array system considering panel flexibility and joint clearance.The deployable solar array model consists of a rigid main
【机 构】
：
Qian Xuesen Laboratory of Space Technology,China Academy of Space Technology,Beijing 100094,China
论文部分内容阅读
In this paper,four novel evaluation indices and corresponding hierarchical optimization strategies are proposed for a deployable solar array system considering panel flexibility and joint clearance.The deployable solar array model consists of a rigid main-body,two panels and four key mechanisms,containing torsion spring mechanism,closed cable loop mechanism,latch mech-anism and attitude adjustment mechanism.Rigid and flexible components are established by Nodal Coordinate Formulation and Absolute Nodal Coordinate Formulation,respectively.The clearance joint model is described by nonlinear contact force model and amendatory Coulomb friction model.The latch time,stabilization time,maximum contact force and impulse sum of the contact force of the solar array system are selected as the four novel evaluation indices to represent the complex dynamic responses of a deployable solar array with clearance joints instead of the lock torque widely used in conventional works.To eliminate the gross errors caused by the nonlinear and non-smooth mechanical properties,a hierarchical optimization strategy based on an adaptive simulated annealing algorithm and a nondominated sorting genetic algorithm is adopted for the solar array system with clearance joints.Results indicate that the effects of panel flexibility on the evaluation index responses and design optimization of the solar array system cannot be neglected.Besides,increasing the weight factor of the stabilization time index of the rigid system may compensate for the differences in optimal results of the rigid flexible coupling system.That may provide some references for optimization design of deployable space mechanisms considering clearance joints.
其他文献
文章采用水热化估算方法对北方地区冬季水工混凝土施工的热能损耗率进行试验.试验分析表明:冬季水工混凝土热能损耗的主因在于其内壁厚度,热能损耗率可通过增加其内壁厚度来有效降低,从而增强冬季水工混凝土施工结构的稳定程度.研究成果对于北方地区冬季水利工程施工设计具有重要参考价值.
Fabrication of the surface micro-texture on the C-plane sapphire is undertaken by a 355 nm Ultraviolet (UV) pulsed laser.The surface micro-textures of sapphire with different laser scanning line spacing ranging from 10 μm to 100 μm are obtained,where the
目前,辽河中上游和回水段仍存在防洪标准低、工程不完善、河道阻水障碍多等问题,为适应工农业生产的发展,保障人民生命财产安全,恢复河流的生态环境,有必要对该河段的中、上游河流和回水部分进行治理,故此对凡河流域上游不同区间设计洪水计算,仅供相关设计部门参考.
The article focuses on the design and application of an active reconfigurable controller that mitigates the effects of gust load and actuator faults on a flexible aircraft.A novel integrated adaptive output feedback scheme is investigated to address the a
Hinged booms are widely used in astrophysics missions;however,the trajectory and deployment velocity are difficult to control because they are usually driven by springs,which limits their application in narrow spaces.Thus,a novel hinged boom is highly req
TC21 titanium alloy,as an important metal to fabricate the aircraft structural compo-nents,has attracted great attentions recently.A TC21 titanium alloy with widmanst(a)tten structure was isothermally compressed.Based on the microstructure observation,the
文章以矿物掺合量、石粉含量、机制砂种类为变量,通过改变单一变量探讨混凝土抗水渗透性、早期开裂受变量变化的影响.结果表明:混凝土早期收缩受弹性模量和集料种类的影响较大,为保证混凝土抗裂性能优先选用弹性模量大的机制砂;机制砂混凝土早期抗开裂性能随石粉含量从1％增大到4％的变化而增强,随石粉含量从4％增大到8％的变化反而减弱;机制砂种类相同情况下,石粉含量越高则混凝土抗渗等级越高;混凝土早期开裂性能随粉煤灰矿物掺合料的掺入而明显下降,未掺矿物掺合料的抗水渗透等级明显低于掺矿物掺合料.
以喀什噶尔河灌区阿瓦提干渠为例,在渠道衬砌结构冻胀力学模型的基础上,充分考虑法向冻胀力及切向冻胀力等的综合作用,将其梯形渠道衬砌结构断裂问题简化为Ⅰ(张拉型)+Ⅱ(剪切型)复合型裂纹扩张问题,并提出对于引水干渠梯形渠道衬砌结构具有普遍适用性的冻胀断裂力学破坏准则,进而对阿瓦提干渠渠坡及渠底衬砌结构冻胀断裂力学模型进行设计,对其渠坡及渠底衬砌板厚度进行计算.分析表明,文章所提出的新疆冻土区灌区引水干渠梯形渠道衬砌结构冻胀破坏力学模型及衬砌板厚度的计算方法符合工程实际,且简单有效,值得推广应用.
以本溪市为例,考虑区域水资源、水生态、工业、生活、农业用水承载力定量测算其水资源压力综合指数.结果表明:在空间上,从西部向东南部本溪市水资源压力综合指数呈逐渐递减趋势,西北部压力指数最大为0.86;从时间上,1967-2020年水资源压力综合指数呈波动上升趋势,特别是2000年后上升趋势更加明显.
This paper presents the topic of using solid rocket propulsion for de-orbiting spacecraft,in order to fulfil space debris mitigation requirements.The benefits and disadvantages of using such means are discussed.A dedicated system can be implemented in the