Wind- and Operation-Induced Vibration Measurements of the Main Reflector of the Nobeyama 45 m Radio Telescope. (arXiv:2003.05134v1 [astro-ph.IM])
<a href="http://arxiv.org/find/astro-ph/1/au:+Hashimoto_I/0/1/0/all/0/1">Ikumi Hashimoto</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Chiba_M/0/1/0/all/0/1">Masakatsu Chiba</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Okada_N/0/1/0/all/0/1">Nozomi Okada</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ogawa_H/0/1/0/all/0/1">Hideo Ogawa</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kawabe_R/0/1/0/all/0/1">Ryohei Kawabe</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Minamidani_T/0/1/0/all/0/1">Tetsuhiro Minamidani</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Tamura_Y/0/1/0/all/0/1">Yoichi Tamura</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kimura_K/0/1/0/all/0/1">Kimihiro Kimura</a>
As deformations of the main reflector of a radio telescope directly affect
the observations, the evaluation of the deformation is extremely important.
Dynamic characteristics of the main reflector of the Nobeyama 45 m radio
telescope, Japan, are measured under two conditions: The first is when the
pointing observation is in operation, and the second is when the reflector is
stationary and is subjected to wind loads when the observation is out of
operation. Dynamic characteristics of the main reflector are measured using
piezoelectric accelerometers. When the telescope is in operation, a vibration
mode with one nodal line horizontally or vertically on the reflector is
induced, depending on whether the reflector is moving in the azimuthal or
elevational planes, whereas under windy conditions, vibration modes that have
two to four nodal lines are simultaneously induced. The predominant mode is
dependent on the direction of wind loads.
As deformations of the main reflector of a radio telescope directly affect
the observations, the evaluation of the deformation is extremely important.
Dynamic characteristics of the main reflector of the Nobeyama 45 m radio
telescope, Japan, are measured under two conditions: The first is when the
pointing observation is in operation, and the second is when the reflector is
stationary and is subjected to wind loads when the observation is out of
operation. Dynamic characteristics of the main reflector are measured using
piezoelectric accelerometers. When the telescope is in operation, a vibration
mode with one nodal line horizontally or vertically on the reflector is
induced, depending on whether the reflector is moving in the azimuthal or
elevational planes, whereas under windy conditions, vibration modes that have
two to four nodal lines are simultaneously induced. The predominant mode is
dependent on the direction of wind loads.
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