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用于精密跟踪的复合轴伺服系统 总被引:2,自引:0,他引:2
一、前言在光学跟踪和测量系统中,为了保证对大加速度目标进行高精度的跟踪和测量,必须有一个精密的跟踪伺服系统,复合轴伺服系统是实现精密跟踪的一种行之有效的途径.该系统是由主跟踪架和安装在主跟踪架上的子跟踪架构成.它的直角坐标系的每一个坐标都具有两根轴,其子轴是位于主轴的轴线上.实际上,复合轴系统是多变量控制系统中的二维关联控制系统的一种型式[1]. 相似文献
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光电精密跟踪的双重复合轴伺服系统 总被引:2,自引:2,他引:2
介绍了用于光电精密跟踪的双重复合轴伺服系统.分析了该系统的伺服控制原理、稳定性、快速性和提高跟踪精度的功能,给出了系统跟踪误差曲线. 相似文献
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针对纬轴工作范围为±20°的三轴跟踪架结构不能跟踪半球空域内所有卫星的问题,本文研究了卫星跟踪原理,结合纬轴受限的三轴结构特点,推导出了三轴之间关系的公式,并由此仿真得出了STTA卫星跟踪策略算法。跟踪仰角70°以上的卫星时,采用方位轴定位式水平式跟踪,这种跟踪方式既利用了水平式结构保精度跟踪天顶附近目标的优势,又克服了地平式结构有天顶跟踪盲区问题;跟踪仰角70°以下的卫星时,采用方位轴随动式水平式跟踪,这种跟踪方式使地平式跟踪方式和水平式跟踪方式有机地结合起来,实现优势互补,达到了更为理想的跟踪效果。该跟踪策略不仅解决了三轴转台纬轴工作范围受限问题,而且能够捕获跟踪半球空域内所有卫星,并保证卫星全程在保精度跟踪范围内。最后设计了实验,证明了该跟踪策略算法的有效性和可行性。 相似文献
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为了满足光学望远镜在诸多新兴领域的产业化需求,结合小口径地平式光学望远镜系统,研制了一套400 mm望远镜跟踪架。首先,为了使跟踪架满足产业化需求并适宜批量生产工艺,对跟踪架进行了模块化设计,并详细说明了方位轴系、俯仰轴系结构,同时分析了轴系理论晃动误差;然后,为了使望远镜系统稳定可靠地工作,即跟踪架需具备较好的静态特性和动态特性,对跟踪架进行力学分析,分析其承载能力和模态特性;最后,为了满足望远镜的指向和跟踪性能,即跟踪架需具备较高的轴系精度,利用千分表实测方位轴系的晃动误差,利用高精度自准直经纬仪、平面反射镜实测俯仰轴系的晃动误差和两轴垂直度误差。分析结果表明,跟踪架具有较高的承载能力和较好的模态特性,其系统一阶谐振频率达到85.16 Hz。检测结果表明,跟踪架具有较高的轴系精度,方位轴系最大晃动误差为3.2″,俯仰轴系最大晃动误差为2.6″,两轴垂直度误差为2.4″。分析及测试结果表明,400 mm望远镜跟踪架结构设计合理可行,满足使用要求。 相似文献
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Inertia friction welding process analysis and mechanical properties evaluation of large rotor shaft in marine turbo charger 总被引:2,自引:0,他引:2
Ho-Seung Jeong Jong-Rae Cho Jung-Seok Oh Euong-Nam Kim Sung-Gyu Choi Man-Young Ha 《International Journal of Precision Engineering and Manufacturing》2010,11(1):83-88
The two aims of this study are first, determining the optimal welding process parameters by using the finite element simulation
and second, determining the optimal tempering temperature by evaluating the mechanical properties of friction welded part
for manufacturing large rotor shaft. Inertia welding was conducted in order to make the large rotor shaft of turbo charger
for low speed marine diesel engine. The rotor shaft is composed of the 310mm diameter disk and the 140mm diameter shaft. Since
diameters of disk and shaft are very different, the integration using friction welding reduces manufacturing cost compared
with the forming process of which a disk and shaft are forged into one body. Finite element simulation was performed, because
inertial welding friction process depended on many process parameters, including axial force, initial revolution speed and
energy, amount of upset, and working time. It is expected that this modeling will significantly reduce the number of experimental
trials needed when determining the optimal welding parameters. Inertia welding was carried out with optimal process parameter
conditions obtained from the simulation results. Welded joint part, made by friction welding, had very poor mechanical properties,
and so it required heat treatment. The base material used in the investigation was SFCMV1 (SANYO special steel, high strength
low alloy Cr-Mo steel) of 140mm diameter. In the study, heat treatment test carried out quenching (950 °C, 4hr, oil cooling)
and tempering (690–720 °C, 6hr, air cooling) for friction welding specimens. The various tests, including microstructure observation,
tensile, hardness, and fatigue tests, were conducted to evaluate the mechanical properties under various heat treatment conditions
after inertia welding. 相似文献
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The noncontact torque sensing in machine shafts is addressed based on the stress induced in a press-fitted magnetoelastic sleeve on the shaft and eddy current sensing of the changes of electrical conductivity and magnetic permeability due to the presence of stress. The eddy current probe uses dual drive, dual sensing coils whose purpose is increased sensitivity to torque and decreased sensitivity to variations in distance between probe and shaft (liftoff). A mechanism of keeping the distance constant is also employed. Both the probe and the magnetoelastic sleeve are evaluated for performance using a standard eddy current instrument. An eddy current instrument is also used to drive the coils and analyze the torque data. The method and sensor described are general and adaptable to a variety of applications. The sensor is suitable for static and rotating shafts, is independent of shaft diameter and operational over a large range of torques. The torque sensor uses a differential eddy current measurement resulting in cancellation of common mode effects including temperature and vibrations. 相似文献
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从实际生产现状分析入手,通过采用3种不同的焊接设备进行焊接工艺试验,对结果进行对比分析,找到气门推杆结合部杆头与杆身焊接的最佳焊接工艺———电容储能焊工艺;并从焊接原理、技术效果、经济效果的分析,论证了数种焊接工艺对气门推杆结合部杆头与杆身焊接品质的影响。 相似文献
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焊接前先对母材进行预热,可以减小焊后残余应力,防止冷裂纹。基于上述原因采用51单片机作为控制器,实现了对209T制动梁端轴焊接预热温度的检测和显示,实践证明该系统可靠性高,操作简便,提高了制动梁端轴的焊接性能。 相似文献
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空间光电跟踪系统动量平衡设计与试验 总被引:1,自引:1,他引:1
研制了空间光电跟踪系统的输出力矩(角动量)和动量自补偿的平衡轮,用于降低光电跟踪系统运动对卫星平台姿态的影响。根据光电跟踪系统对目标捕获和跟踪成像的指标要求,针对其频繁启动、速度和加速度变化范围大、速度频繁过零等区别于卫星姿态控制用平衡轮的特点,基于角动量平衡原理设计了一种平衡轮。通过有限元法完成了平衡轮的模态分析和结构优化,建立了包含平衡轮的光电跟踪系统的机电动力学数学模型,利用Matlab/Simulink对光电跟踪系统的方位轴系进行了模型的仿真计算。为验证其可行性,研制了一套平衡轮原理样机,提出了基于单轴气浮平台的平衡轮性能测试方法,并完成了模拟方位轴系的残余角动量检测。仿真和试验结果显示,平衡轮的使用将光电跟踪系统对平台的残余角动量输出减小了96%,表明所设计的平衡轮结构和控制系统合理可行,能够满足空间应用的需求。 相似文献