![]() ![]()
A summary of the first IVS Directing Board meeting is provided, including the near-term plan for IVS activities. The IVS enjoys broad international and institutional participation, with components from 14 countries and 29 different organizations. The IVS will begin its work with 73 Components, 229 Associate Members, and a 14-member Directing Board. The Steering Committee will complete its activities in early February 1999 when the initial Directing Board of the IVS has its first meeting. The IVS was established by a Steering Committee set up by the CSTG VLBI Subcommission in April 1998. Coordination of Space Techniques for Geodesy and Geodynamics" or CSTG. The services all originated from the IAG's Commission VIII "International. The IVS will be one of three international geodetic services, the others being the IGS (International GPS Service) established in 1994, and the ILRS (International Laser Ranging Service) established in 1998. The International VLBI Service for Geodesy and Astrometry (IVS) will be officially inaugurated on 1 March 1999. It indicates the joint calibration and compensation algorithm can effectively compensate for the errors caused by the inclinometer and obtain higher positioning accuracy. Experiment results show the root mean square errors of the longitude and latitude are 0.00309∘ $$, and the mean distance error is 397.46 m, which is far less than the mean distance error 3629.27 m of the traditional calibration algorithm. #Vectorial astrometry by c a murray pdf verificationFinally, a ground test platform is built and the experimental verification of the joint calibration and compensation algorithm of inclinometer error is accomplished. Then, a joint calibration and compensation algorithm for the inclinometer installation and instrument errors is presented based on coordinate transformation relationship and error propagation characteristics. First, based on the principle of celestial positioning, the influence analysis model of the inclinometer error on the positioning accuracy is built according to the definition of inclinometer installation error and instrument error, which indicates the traditional algorithms are not suitable for tilted platforms. To improve the positioning accuracy of the tilted platform, a joint calibration and compensation algorithm of the inclinometer's installation and instrument errors is proposed. But the installation error of the inclinometer is coupled with the error of the instrument itself, and there is no effective way to measure the two errors separately. Due to the installation and instrument errors of the inclinometer, it is difficult for tilted platforms to obtain high‐precision positioning results. The application of celestial navigation based on inclinometer to aircraft in near‐earth space and planetary rovers is a significant development direction. NOVAS source code, auxiliary files, and documentation are available from the USNO website (). In the Version 3.1 C edition, the ephemeris-access functions have been revised for use on 64-bit systems and for improved performance in general. Future versions will expand the functionality of the Python edition to exploit the object-oriented features of Python. #Vectorial astrometry by c a murray pdf codeThe Python edition uses the computational code from the C edition and currently mimics the function calls of the C edition. NOVAS Version 3.1 introduces a Python edition alongside the Fortran and C editions. NOVAS can be easily connected to the JPL planetary/lunar ephemerides (e.g., DE405), and connections to IMCCE and IAA planetary ephemerides are planned. NOVAS algorithms for aberration and gravitational light deflection are equivalent, at the microarcsecond level, to those inherent in the current consensus VLBI delay algorithm. NOVAS Earth orientation calculations match those from SOFA at the sub-microarcsecond level for comparable transformations. Equinox-based quantities, such as sidereal time, are also supported. NOVAS uses IAU recommended models for Earth orientation, including the IAU 2006 precession theory, the IAU 2000A and 2000B nutation series, and diurnal rotation based on the celestial and terrestrial intermediate origins. portions of The Astronomical Almanac and a number of telescope control systems. NOVAS is used for a wide variety of applications, including the U.S. NOVAS also provides access to all of the building blocks that go into such computations. The library can supply, in one or two subroutine or function calls, the instantaneous celestial position of any star or planet in a variety of coordinate systems. #Vectorial astrometry by c a murray pdf softwareThe Naval Observatory Vector Astrometry Software (NOVAS) is a source-code library that provides common astrometric quantities and transformations to high precision. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |