The technology of estimating position and pose of spacecraft based on laser lidar is a research hotspot of on-orbit services.For the position and pose estimation of failure spacecraft , the technology of general graph-based optimization SLAM was applied to the research of noncooperative target in space.In order to solve the problem of accumulative error generated in the dynamic scene ,an improved SLAM algorithm based on detection of prior submap according to the characteristics of failure spacecraft was proposed .In this algorithm , laser lidar and inertia measurement unit were used to sample the point cloud data of failure spacecraft as well as the environment and the movement information of service spacecraft , to construct a relative pose graph of service scenario .Then the method of detecting prior submap was used to generate the constraints of discontinuous poses.At last ,the constraints information was used to optimize the result of pose graph.The simulation result shows that the method decreases the cumulative deviation and improves precision of relative position and pose estimation compared to general SLAM algorithm ,providing information for on-orbit tasks such as navigation and controlling.

针对空间攻防领域的需求,基于微小卫星编队提出一种聚光操控技术,利用编队内卫星的协同控制聚集太阳光到目标卫星上,造成局部过热甚至烧毁.首先,基于CW方程设计微小卫星聚光编队,分析表明该编队聚光效率较高但需要一种高精度姿轨控算法来支撑.然后,根据任务需求设计基于卫星本体系的姿轨耦合二阶滑模控制算法.最后,通过仿真证明该算法满足编队卫星实现聚光跟随的要求,验证了微小卫星聚光编队在空间攻防领域的可行性.

目前国内外针对旋转式导航系统的研究表明,调制转台的性能直接影响到系统的导航精度.提出利用新型超声电机位移分辨率高、响应快、电磁兼容性好等特点,研制了高精度、低成本的超声电机调制转台,并实现了转台的非线性控制,从而增强导航系统旋转调制效果,进一步提高导航精度.相比于体积和功耗较大的常规电磁驱动旋转平台,该超声电机转台控制精度优于40”,响应时间优于5ms,体积小,且无磁影响,有利于实现低成本、低精度的MEMS旋转式导航系统的高精度应用,并进一步推动低成本微小卫星的应用和发展.

在硅基底上利用喷射电沉积法制备铜/钴多层膜和单层纯铜膜,研究了多层膜的形貌、多层膜和单层铜膜与基体的结合力以及划痕方向对膜基结合力的影响.结果表明:对硅基底进行抛光处理可使膜基结合力减小,粗化处理可在一定程度上提高膜基结合力;多层膜与基底的结合力大于单层铜膜与基底的结合力;当划痕方向平行于工件运动方向时,膜层中的内应力变化不均匀,很容易造成应力累积而使得临界载荷减小,从而使得膜基结合力明显小于划痕方向垂直于工件运动方向时的膜基结合力.

采用脉冲摩擦喷射电沉积和直流喷射电沉积分别在石墨基底上制备了纳米晶镍镀层,利用扫描电镜和X射线衍射分析了脉冲占空比和脉冲频率对镍镀层的表面形貌、晶粒的择优取向及平均晶粒尺寸的影响.结果表明脉冲摩擦喷射电沉积较直流喷射电沉积的沉积效果有较大提高,在喷嘴流量为200L/h,平均电流密度为80A/dm2,阴极转速为6r/min的条件下,脉冲占空比为50％,脉冲频率为2000Hz时可以获得表面较为平整光亮、组织致密的Ni沉积层.

Cobalt coatings on graphite substrates were prepared by conventional jet electrodeposition and friction aided jet electrodeposition.Their surface micrograph and micro-hardness were studied by SEM and micro hardness tester,respectively.Under the two experimental conditions,the hardness of cobalt coatings increases and then decreases with increasing average current density,and simply goes up when the cathode rotation speed increases.However,the friction aided coatings exhibit even higher microhardness,the highest micro-hardness of which reached 581Hv.In addition,the deposition layers change from island growth to uniform deposition.