28 January 2015 Dynamic analysis and control of mirror segment actuators for the European Extremely Large Telescope
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Segmented primary mirror telescopes require dedicated piston-tip-tilt actuators for optimal optical performance. Netherlands Organisation for Applied Scientific Research (TNO) has developed various prototypes of such actuators, in particular for the E-ELT. This paper presents the dynamics analysis and feedback control results for a specific two-stage prototype. First, the dynamics of the actuator in interconnection with the to-be-positioned mass has been analyzed, both using frequency response measurements and first principles modeling, resulting in a detailed understanding of the dynamic behavior of the system. Next, feedback controllers for both the fine and the coarse stage have been designed and implemented. Finally, the feedback-controlled actuator has been subjected to a realistic tracking experiment; the achieved results have demonstrated that the TNO actuator is able to suppress wind force disturbances and ground vibrations with more than a factor 103, down to 1.4 nm root mean square, which is compliant with the requirements.
© 2015 Society of Photo-Optical Instrumentation Engineers (SPIE)
Gert Witvoet, Remco den Breeje, Jan Nijenhuis, René Hazelebach, Niek Doelman, "Dynamic analysis and control of mirror segment actuators for the European Extremely Large Telescope," Journal of Astronomical Telescopes, Instruments, and Systems 1(1), 019003 (28 January 2015). https://doi.org/10.1117/1.JATIS.1.1.019003 . Submission:


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