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《北华航天工业学院学报》2021,31(1):1-4
设计了一种可变形的陆地两栖八面体机器人,其主要由传动模块、伸缩模块、传动机构和顶点模块构成。机器人在陆地上的运动主要是通过控制伸缩模块中的杆件伸缩量来改变机器人重心位置,实现机器人沿着指定方向进行翻转;空间运动通过调整螺旋桨的姿态来调整机器人飞行的方向及方式,从而确定机器人飞行的轨迹。给出了机器人在地面运动的重心计算公式,机器人运动学正解和反解的计算方法以及机器人在空间飞行过程中的动力学模型,并通过软件对于机器人的动力学进行了仿真,验证了前面理论分析的正确性,该分析结果对于机器人的分析以及运用都具有十分重要的作用。 相似文献
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“人马”(Centaur)是由NASA约翰逊航天中心机器人系统技术部门,与美国国防高新技术研究计划局合作设计的半人形机器人(如图)。它是机器人航天员(Robonaut)上躯干和4轮机动底部组成的。机器人航天员是人形机器人,其大小和灵活度与穿着航天服的航天员相当。机动底座能够以6km/hr的速度行驶。 相似文献
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美国航空航天局(NASA)6月18日在佛罗里达州卡纳维拉尔角使用宇宙神5型运载火箭成功地发射了“月球侦察轨道器”(LRO)和“月坑观测与探测卫星”(LCROSS).用于对月面进行测绘,并寻找水冰。这是NASA自1998年发射“勘月者”探测器以来首次发射月球探测器。这两个探测器是NASA为重新把人员送到地球轨道以外的地方而派出的首批机器人开路先锋。 相似文献
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面向空间太阳能电站在轨装配的爬行机器人关键技术 总被引:1,自引:0,他引:1
提出一种可在薄膜和桁架表面爬行的足式机器人,以完成对空间太阳能电站由薄膜 桁架模块在轨组装。机器人系统由操作工具搭载平台、压电驱动式多关节腿、微结构修饰附着足等组成。在此基础上,基于仿生理论,对自然界具有高攀爬能力的生物足端微结构进行了分析与仿真,并结合桁架的杆类结构和薄膜的柔性结构的特点,开展了机器人微结构修饰足特性的附着特性研究。利用离散元 多体动力学耦合仿真平台,对机器人在桁架结构和薄膜结构上的爬行过程进行了仿真研究,为爬行机器人的运动控制提供了依据。通过上述研究,验证了利用爬[JP2]行机器人系统实现薄膜 桁架模块在轨操作与组装的方案可行性,为空间太阳能电站在轨装配任务提供了技术储备。[JP] 相似文献
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日本宇宙开发事业团(NASDA)为了获得空间机器人技术和交会对接技术,开发了工程试验卫星-Ⅶ(EST-Ⅶ)。在1997年,用H-Ⅱ火箭将ETS-Ⅶ发射到550公里的地球轨道,ETS-Ⅶ有一个长约2米的6自由度手臂,用来进行空间远程机器人实验。设计远程机器人实验系统的目的是用来减轻航天员的工作负担,并使那些非机器人专业的用户使用起来更加容易,这套实验系统由星上机器人系统和地面控制系统组成。这篇文章具 相似文献
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美国国防高级研究计划局F6项目发展研究 总被引:3,自引:3,他引:0
2009年11月25日,美国国防高级研究计划局(DARPA)将分离模块航天器(F6)研究项目的第二阶段研究合同授予轨道科学公司,合同为期一年,总价7460万美元。这一事件说明美国的分离模块航天器项目取得了阶段性成果。文章介绍了分离模块航天器的概念和项目进展,对以价值为中心的航天器设计理念进行了分析和探讨,并得出了几点启示和建议。 相似文献
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Antenna for precise orbit determination 总被引:2,自引:0,他引:2
Johan Wettergren Magnus Bonnedal Per Ingvarson Bo Wstberg 《Acta Astronautica》2009,65(11-12):1765-1771
The ESA SWARM mission will consist of three satellites that will measure the Earth magnetic field. The system calls for metre accuracy knowledge of the measurement locations. To achieve this a GPS receiver is used. At least four GPS signals are tracked to determine the code and carrier ranges, from which the position can be derived. The accuracy improves when using more GPS satellites and by averaging over many measurements. The latter is achieved in ground processing with a model-based orbit prediction, resulting in cm accuracy. The main error contributions in the processing are often measurement errors due to satellite multi-path effects. The multipath effects are characterized by measuring the antenna on a 1.5 m mock-up, representing the 9 m long satellite. In order to verify that the mock-up is representative, extensive electromagnetic simulations were made. The simulations included the antenna and the complete satellite and were then reduced to the antenna and a section of the satellite. The actual design of the antenna was performed with several levels of software. First, a fast bodies-of-revolution simulation found a geometry with the right coverage. Then, a finite element method simulation allowed us to match the antenna at two frequencies simultaneously. 相似文献
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The strain–stress state of the solid propellant rocket engines (SPREs) is simulated under impact. The effect of orientation of elastic and strength properties of orthotropic organoplastic shell material on the strain–stress state of the solid propellant is investigated. Normal and oblique impact of single steel cylinder projectiles, both simultaneous and at different times of multiple, converging steel spheric particles with SPRE are investigated in this study. The investigation is conducted numerically. The numerical modeling was carried out in a three-dimensional formulation by the method of finite elements for the continuous approach of the mechanics of a deformable solid. The destruction of the anisotropic material is described by the tensor-polynomial criterion of the fourth degree, which takes into account the influence of hydrostatic pressure. 相似文献
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The traditional absolute calibration based on oscilloscopic observation is not suitable for crosslink transmitter. A new calibration algorithm is developed by using a digital signal processing technique. The output signal of crosslink transmitter and the pulse per second signal are sampled in synchronization. At first, the delay reference is determined according to straight line fitting for the signal level stepping segment. The sampling data of crosslink transmitting signal is decimated and then phase acquisition processing is made to determine the initial synchronization point. A fine search for the start of the pseudo random code has been processed between front and rear of the initial synchronization point. Finally, the transmitter delay can be obtained according to the sampling frequency and the calibration delay of the test cable and attenuator. Compared with the oscilloscopic observation method, the analysis and test results show that the proposed technique has overcome the faults caused by whole chip ambiguity and the calibration accuracy can be improved by an order of magnitude. 相似文献
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《Acta Astronautica》2014,93(1):321-332
With an increase in the use of small, modular, resource-limited satellites for Earth orbiting applications, the benefit to be had from a model-based architecture that rapidly searches the mission trade-space and identifies near-optimal designs is greater than ever. This work presents an architecture that identifies trends between conflicting objectives (e.g. lifecycle cost and performance) and decision variables (e.g. orbit altitude and inclination) such that informed assessment can be made as to which design/s to take on for further analysis. The models within the architecture exploit analytic methods where possible, in order avoid computationally expensive numerical propagation, and achieve rapid convergence. Two mission cases are studied; the first is an Earth observation satellite and presents a trade-off between ground sample distance and revisit time over a ground target, given altitude as the decision variable. The second is a satellite with a generic scientific payload and shows a more involved trade-off, between data return to a ground station and cost of the mission, given variations in the orbit altitude, inclination and ground station latitude. Results of each case are presented graphically and it is clear that non-intuitive results are captured that would typically be missed using traditional, point-design methods, where only discrete scenarios are examined. 相似文献
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王玉新 《华北航天工业学院学报》2000,10(2):53-57
运动的破缺产生差异,导致涨落,造成对系统原有方向、轨道的偏离,致使事物发展与进化,由此带来一系列富有生机和活力的启示。作为系统内在机制的协同与竞争,也深深地楔人了我们的生活。 相似文献
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针对TDMA多时隙信号不连续,通信时隙外噪声以及其它用户信号影响时/频差参数估计的问题,首先证明了多时隙多普勒频差信号具有相参性,指出多时隙信号在相关处理中能量是可以积累的;在此基础上,根据通信时隙外噪声、其它用户信号与特定用户信号在时域上的可分离特性,提出基于解调分选的TDMA时/频差参数估计方法,并推导分析了该方法的处理性能。试验结果表明,提出的方法可以实现TDMA信号中多用户信号的时/频差参数联合估计,可以有效降低通信时隙外噪声与其它用户信号对参数估计精度的影响。 相似文献
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结构局部刚度变化对小卫星动特性影响 总被引:4,自引:0,他引:4
首先针对模块式小卫星动特性进行灵敏度理论分析,分析目标是寻找提高结构动特性的局部位置和参数。然后基于有限元法分析改变局部刚度对结构动特性的影响。小卫星结构动特性分析计算的主要问题是建立计算成本可控的有限元模型,本文详细讨论了小卫星有限元模型建模方法和简化途径,并通过7个算例考察改变模块底板局部刚度、改变适配器支撑刚度、模块问设置弹簧模拟阻尼器等对小卫星结构动特性的影响。灵敏度分析和计算表明,影响动特性的主要因素是模块盒底板刚度和星箭适配器的支撑刚度;增加模块局部刚度以及适配器支撑刚度可以屏蔽星体摆动和包带联结部位的某些频率,同时可以减缓部分中间模块的振幅;在部分模块间设置弹簧可以模拟阻尼器或减振器的效果。另一方面,降低适配器刚度可以增加隔振作用。因而优化模块刚度分布和支撑刚度分布是改进动力学性能的有效途径。本文分析为模块式小卫星动力学修改以及多功能结构设计和主动振动设计提供依据。 相似文献
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薄壁内、外半管冲压成形工艺参数模拟优化设计 总被引:2,自引:0,他引:2
针对内、外半管的结构特点,分析计算冲压成形主要工艺参数及毛坯尺寸,运用有限元分析软件ANSYS/LS-DYNA,对内、外半管的成形过程进行了模拟。研究了不同压边力及不同冲压速度对零件拉深成形的影响,分析了零件的成形工艺及其起皱缺陷,优化了毛坯形状,避免了成形过程中的缺陷,获得了理想的毛坯形状和工艺参数。 相似文献