DocumentCode
2696252
Title
Control characteristics of the ALMA Nutator
Author
Jiang, Homin ; Chen, Ming-Tang ; Han, Johnson C.
Author_Institution
Acad. Sinica Inst. of Astron. & Astrophys., Taipei, Taiwan
fYear
2010
fDate
8-10 Sept. 2010
Firstpage
962
Lastpage
966
Abstract
The control of a 75 centimeter diameter Atacama Large Millimeter/submillimeter Array (ALMA) nutating subreflector, or Nutator, to meet the specifications of 10 millisecond (ms) settle time and 1.3 arc-second pointing error involves tremendous challenges. The ALMA Nutator has been under development since 2003, and we have improved its dynamic characteristics through robust PID control algorithm, increasing the open loop bandwidth to beyond 200Hz and shortening the settle time to 20 ms. A mode switching associate with model following control scheme is also presented, and expected to improve the settle time and pointing error.
Keywords
radiotelescopes; robust control; three-term control; ALMA nutator; Atacama large millimeter-submillimeter array; model following control scheme; nutating subreflector; open loop bandwidth; robust PID control algorithm; Field programmable gate arrays; Mathematical model; Mirrors; Switches; Transfer functions; Voltage control;
fLanguage
English
Publisher
ieee
Conference_Titel
Control Applications (CCA), 2010 IEEE International Conference on
Conference_Location
Yokohama
Print_ISBN
978-1-4244-5362-7
Electronic_ISBN
978-1-4244-5363-4
Type
conf
DOI
10.1109/CCA.2010.5611324
Filename
5611324
Link To Document