DOI: 10.17586/1023-5086-2018-85-09-37-45

Study on a new floatation support algorithm based on a 1.2 m thin primary mirror

Dai, Xiaolin, Xian, Hao, Tang, Jinlong, Zhang, Xuejun, Zhang, Yudong

Publication in Journal of Optical Technology

For Russian citation (Opticheskii Zhurnal):

Xiaolin Dai, Hao Xian, Jinlong Tang, Xuejun Zhang, Yudong Zhang Study on a new floatation support algorithm based on a 1.2 m thin primary mirror (Новый алгоритм для плавающей подвески тонкого главного зеркала диаметром 1,2 метра) [на англ. яз.] // Оптический журнал. 2018. Т. 85. № 9. С. 37–45. http://doi.org/10.17586/1023-5086-2018-85-09-37-45

Xiaolin Dai, Hao Xian, Jinlong Tang, Xuejun Zhang, Yudong Zhang Study on a new floatation support algorithm based on a 1.2 m thin primary mirror (Новый алгоритм для плавающей подвески тонкого главного зеркала диаметром 1,2 метра) [in English] // Opticheskii Zhurnal. 2018. V. 85. № 9. P. 37–45. http://doi.org/10.17586/1023-5086-2018-85-09-37-45

For citation (Journal of Optical Technology):

Xiaolin Dai, Hao Xian, Jinlong Tang, Xuejun Zhang, and Yudong Zhang, "Study on a new floatation support algorithm based on a 1.2 m thin primary mirror," Journal of Optical Technology. 85(9), 551-558 (2018). https://doi.org/10.1364/JOT.85.000551

Abstract:

Floatation support is often used to eliminate the extra interaction forces of the large primary mirror's fixed points during the mirror's active correction in order to maintain the mirror's position in the cell. This paper introduces the principle of floatation support as well as its 3 force distribution algorithms. A new floatation support algorithm is proposed, it directly utilizes the image of the mirror surface instead of the fixed points' feedback interaction forces to calculate the adjusting forces of the actuators. Simulations are conducted on a 1.2 m thin primary mirror to verify and compare the performances of all the algorithms, the results show the new algorithm is as effective as the best traditional algorithm – it reduces the residual root mean square of the mirror surface to less than 3.5 nm. Performance study of this new algorithm shows that the new algorithm is more sensitive to the fixed point's position deviation and the Shack-Hartmann's detection error than the forcebased-algorithm, but as it doesn't need the force sensors to feedback the interaction forces, it is more helpful to simplify the hardware requirement of floatation support.

Keywords:

active optics, thin primary mirror, floatation support, mirror image, axial fixed points

OCIS codes: 230.4040, 300.6300

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