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291.
《Space Policy》2014,30(3):174-177
The European Space Agency (ESA) is pursuing an independent strategic planning process for consolidating a destination driven (LEO, Moon, Mars) space exploration strategy. ESA's space exploration strategy is driven by the goals to maximise knowledge gain and to contribute to economic growth. International cooperation is a key pillar of ESA's strategy as it is considered both, an enabler for achieving common goals and a benefit, opening new perspective for addressing future challenges. The achievement of ESA's space exploration strategy is enabled through international partnerships. The interagency coordination process conducted within the framework of the International Space Exploration Coordination Group (ISECG) plays an important role in laying the foundations for future partnerships. It has achieved so far the development of a common vision for space exploration, a common plan for implementing the vision in the form of the Global Exploration Roadmap, as well as a common approach for articulating the value of global space exploration. ESA has been a strong promoter and supporter of the interagency coordination process conducted within ISECG and thanks to its unique expertise in international cooperation the Agency has contributed to its success. 相似文献
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分析重力梯度对在轨运行的自由漂浮空间机器人姿态运动影响。由Lagrange方法建立自由漂浮空间机器人受重力梯度扰动的非线性动力学模型。首先,考虑无控关节自由状态,分析重力梯度对关节运动的影响。其次,利用相平面轨迹分析重力梯度对自由漂浮系统姿态运动影响。最后,由速度偏差曲线分析重力梯度对机械臂的影响。结果表明,当作用时间接近轨道周期或更长时,重力梯度引起的关节偏差已十分显著,且这种扰动作用主要由轨道偏心率决定;关节锁定时俯仰姿态受扰运动有周期振动与翻滚两种形式,若初始角速度满足一定限值可以保证俯仰运动不发生翻滚;当机械臂长时间工作时,忽略重力梯度将产生明显的末端定位误差。 相似文献
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面向在轨对接与装配任务,提出了多目标融合的冗余度空间机械臂碰前轨迹优化方法。通过分析任务特点,阐述了空间机械臂碰前的多重任务目标。针对由空间机械臂连续轨迹跟踪、碰撞姿态控制及碰撞冲量幅值优化三个目标组成的第一类任务,通过设置任务优先级融合多目标并采用基于主任务零空间的方法实现对碰前轨迹的优化;而对由空间机械臂点到点规划、碰撞姿态控制及碰撞冲量幅值优化三个目标组成的第二类任务,通过设置任务权重将多目标融合并采用遗传算法对碰前轨迹进行优化。以典型七自由度机械臂为例开展仿真实验,验证了提出的轨迹优化方法的有效性。 相似文献
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To develop an understanding of near-Earth space's response to solar activities and the coupling among different layers in geospace, China has initiated a ground base program to monitor China's geospace environment called the Meridian Space Weather Monitoring Project (Chinese Meridian Project). The effort consists of a chain of 15 ground-based observatories located roughly along 120°E longitude and 30°N latitude. Each observatory is equipped with multiple instruments to measure key parameters such as the baseline and time-varying geomagnetic field, as well as the middle and upper atmosphere and ionosphere from about 20 to 1000 kilometers. This project started collecting data in 2012. We will give a brief introduction to the Chinese Meridian Project, and present recent scientific results mainly in ionospheric and atmospheric studies. 相似文献
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With the complete success of the 2nd stage of Chinese Manned Space Program (CMSP), several science researches have been performed on Tiangong-1 experimental spacelab, which was docked with three Shenzhou spaceships one after another. The China's real spacelab, Tiangong-2 will be launched in 2015, docked with a Shenzhou spaceship soon. After six months, it will be docked with the first Chinese cargo ship (Tianzhou-1). More space science researches, involving with space biology, fluid physics, fundamental physics, materials science, Earth science, astronomy and space environmental science, will be operated on Tiangong-2 spacelab, and crewed and cargo spaceships. Furthermore, the considerable large-scale space utilization of Shina's Space Station is planned. The research fields include yet not limited to space medicine and physiology, space life science and biotechnology, fluid physics and combustion in microgravity, space material science, and fundamental physics in microgravity, space astronomy, Earth science, space physics and space environment utilization, technology demonstration. 相似文献
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In the past two years, space life science research in China is characterized by a wide area of basic researches for providing foundation for the future China Space Station. The effect of microgravity and radiation was further studied from physiology phenomena to the level of bio-molecule mechanisms. Chinese space life science is maturing in a new era of comprehensive development. Here, we review and summarize researches on space life sciences which were contributed by Chinese scientists. 相似文献