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

京都大学天文学系目前正在利用建造下一代极大望远镜所需的技术进行3.8m望远镜项目。在该研究项目中，作为该望远镜项目的一部分，我们进行了以下研究。 1.镜面支撑系统的设计与开发我们试制了一种机械部件来支撑具有相同承载力的分段镜，该支撑系统在望远镜的任何仰角下都不会产生任何扭矩，放置在狭窄的空间中。后面的空间通过这次试制，我们发现了一些问题，例如间隙和关节的安装精度。2.开发调节镜支撑系统的执行器系统我们改进并试制了调节镜面支撑系统的执行器系统。改进后的镜面支撑系统可以放置在桁架结构的节点正下方，并且通过连接到镜面支撑系统的加压弹簧，即使在小负载条件下也能稳定运行。 3.非接触式传感器的精确位置测量测试继续进行非接触式电感传感器的分段镜相对位置测量的稳定性测试，我们发现测量值对分段镜之间的相对位置测量非常敏感。弯曲电缆和面板静电也影响传感器的新驱动电路显示出较小的读出噪声，但在长期稳定性测试中我们将驱动电路具有稳定性和低读出。 4. 测量分段镜之间相位差的基本技术的发展我们设计了使用望远镜焦点上的扩散激光和分段镜之间附着的许多半反射镜的相位差测量系统，其基本原理得到了光学证实。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。