Research and Development of Control Technology of Large Segmented Mirrors

大分段镜控制技术的研究与发展

• 批准号: 17340053
• 负责人: IWAMURO Fumihide
• 金额: $ 3.52万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17340053/
• 关键词: Optical and NIR Astronomy; Fine Polishing; Precise Measurement; Grinding; Accurate Position Control; 研削加工

In the department of astronomy of Kyoto University, the 3.8m telescope project is now in progress using the technology required to construct the next-generation extremely large telescope. In this research project, we conducted the following studies as a part of this telescope project.1. Designing and development of the mirror support systemWe carried out the trial manufacture of a mechanical part to support the segmented mirror with the same bearing power. The support system does not yield any torque under any elevation angle of the telescope, placed in the narrow space behind the mirror. We found a few problem such as backlash and the mounting accuracy of a joint from this trial manufacture.2. Development of actuator system to adjust the mirror support systemWe improved and also carried out the trial manufacture of the actuator system, which adjust the above mirror support system with an accuracy of 〜10nm. The improved actuator can be placed just below the nodes of the truss structure … More , and is stably-operated even under a small load condition by the pressurized spring attached to the actuator axis driven with a harmonic-gear.3. Test of the noncontact sensor for the accurate position measurementThe stability test of the noncontact inductance sensor for the relative position measurement among the segmented mirrors was continued. We found that the measured value is quite sensitive to bending the cables and also to the static of the facing plate. The new driving circuit of the sensor shows a small readout noise, but somewhat unstable in the long-term stability test. We will investigate the driving circuit having stability and low readout noise.4. Development of basic technologies to measure the phase differences between the segmented mirrorsWe designed the phase-difference measurement system using a spreading laser on the telescope focus and many half mirrors attached between the segmented mirrors. The basic principle was confirmed by the optical test in the laboratory. The next step is the demonstration of the fastest procedure to adjust the mirror position using the wavelength switching capability of the tunable laser. Less

京都大学天文系目前正在利用建造下一代超大望远镜所需的技术进行3.8m望远镜项目。在本研究项目中，作为望远镜项目的一部分，我们进行了以下研究： 1．反射镜支撑系统的设计与开发我们进行了机械部件的试制，以相同的承载力支撑分段反射镜。支撑系统放置在镜子后面的狭窄空间中，在望远镜的任何仰角下都不会产生任何扭矩。本次试制发现接头间隙、安装精度等问题。 2．开发调节镜支撑系统的执行器系统我们改进并试制了执行器系统，以〜10nm的精度调节上述镜支撑系统。改进的执行器可以放置在桁架结构的节点正下方，并且通过连接到由谐波齿轮驱动的执行器轴上的加压弹簧，即使在小负载条件下也能稳定运行。 3．非接触式传感器精确位置测量测试继续进行非接触式电感传感器用于分段镜间相对位置测量的稳定性测试。我们发现测量值对弯曲电缆以及面板的静电非常敏感。新型传感器驱动电路显示出较小的读出噪声，但在长期稳定性测试中有些不稳定。我们将研究具有稳定性和低读出噪声的驱动电路。4．开发测量分段镜之间相位差的基础技术我们设计了相位差测量系统，该系统使用望远镜焦点上的扩散激光和连接在分段镜之间的许多半反射镜。其基本原理已通过实验室的光学测试得到证实。下一步是演示使用可调谐激光器的波长切换功能来调整镜子位置的最快程序。较少的