Abstract Details
| Name: TARUN KUMAR SHARMA Affiliation: INDIAN INSTITUTE OF ASTROPHYSICS Conference ID: ASI2015_660 Title : A Direct Dive based Telescope for MASS-DIMM Instrument Authors and Co-Authors : Padmakar singh Parihar Abstract Type : Poster Abstract Category : Instrumentation and Techniques Abstract : At Indian Institute of Astrophysics we have begun a programme to develop site survey instruments. The instruments are developed as a part of the site survey program for the NLOT (National Large Optical Telescope), which will be an 8-10 meter class state of the art telescope. Extinction and sky brightness Monitor, and IR sensor based All Sky Scanning Cloud Monitor are designed and developed. From TMT Project USA a MASS-DIMM device has been acquired. The Multi-Aperture Scintillation Sensor (MASS) is a device which measures the scintillation effect in stellar light and provides a vertical structure of atmospheric turbulence. Whereas the DIMM uses the fluctuation in the phase of the incoming wavefront, and provides the seeing information. This device however requires lot of modifications in the software as well as a very sturdy telescope. One of the prime requirements of the instrument is that it needs very stable telescope which can work in open and windy condition. The telescope will be an Alt-Az mount telescope. In order to reduce wind induced shaking/disturbances, the cross section area of the telescope is minimized. Telescope truss is made as light weight as possible to have a fast response. We also make use of Direct Drive Technology. This technology relies on coupling the specially designed motors to the load axis directly without any intermediate reduction system (gear, timer belts, friction drive etc.). The driver required to operate direct drive motors are designed and developed in house. In addition to driver, the telescope controller and control electronics for optical encoders and position sensors are also developed. A dedicated GPS (Global Positioning Device) system will be integrated with control electronics to very precisely obtain the time and position information. This poster covers all the aspect of the telescope like mechanical design, motors, motor drive and telescope controller. We also present the results of different laboratory experiments conducted on the direct drive motor, motor drive and controller. |