摘要
随着光学遥感器分辨能力的不断提高和口径的不断增大,导致遥感器的重量越来越重,使得载体无法承受。针对此问题,提出了对薄反射镜进行主动支撑的方式,以解决口径大、重量重的问题。利用有限元分析和数学理论相结合的方法在对反射镜施加垂直镜面1g加速度(g=9.80665m/s2为重力加速度)和10℃的温升载荷情况下,对薄反射镜的位移驱动器数量及分布是否合理进行了分析计算,得出了反射镜变形最小时的各促动器的位移量,然后把位移量输入到有限元中相应的节点,计算出了校正后反射镜的面形指标能够达到光学成像要求。具体对Φ500mm、厚3mm的反射镜进行了分析,初步计算的3点和9点支撑的变形值分别为26μm和2.4μm,不能满足系统的成像要求。当运用数学方法计算支撑促动器的间距为72mm时,得出支撑点数为107个,由此再进行有限元分析,得出薄反射镜的面形值,PV值和RMS值分别为119nm和31nm,满足系统的成像要求。分析结果表明,利用数学理论与有限元仿真分析相结合的方法,在薄反射镜变形控制中是可行性的,并为主动光学实验提供了数值依据。
With the resolving power of optical remote sensor improving, aperture increasing, the carrier can not afford because of heavier remote sensors. To solve this problem, the way of active support thin mirror is provided to solve large aperture and weight problems. Whether number of displacement actuators and distribution is reasonable for thin mirror support through adopting finite element analysis and mathematical method of combining theory under lg vertical acceleration imposed on mirror surface and 10℃ temperature rise is calculated. The actuator＇ s displacement is gained when the mirror deformation is smallest. Mirror surface shape corrected is calculated to achieve the optical imaging re- quirements when the displacements are entered into the finite element displacement of the corresponding node. Φ500mm, 3mm thick mirror is analyzed. Mirror deformation is 26μm and 2. 4μm with 3 and 9-point support through preliminary calculation, the imaging system can not meet the requirements. Support actuators~ space calculated is 72ram using math- ematical method. Number of support obtained is107. Mirror surface shape is analyzed through finite element analysis method. PV value is llgnm, RMS value is 31nm The results meet the system imaging requirements. The results show that the way is feasible to apply mathematical theory and simulation to deformation control of thin mirror. A numerical basis is provided for active optics experiment.
出处
《光学技术》
CAS
CSCD
北大核心
2011年第4期438-441,共4页
Optical Technique
关键词
主动光学薄镜
支撑技术
驱动
active optical thin mirror
support technique
actuator
