Positioning the GPS Benchmarks of King Mongkut,s University of Technology Thonburi

Abstract

The objective of this research is to study and apply a satellite surveying method, GlobalPositioning System (GPS), in constructing and positioning eight referenced permanent benchmarkswith high accurate coordinates. All benchmarks are located spread over the areas of two campusesi.e., King Mongkut's University of Technology Thonburi (KMUTT) at Toongkru and Bang Khuntiencampuses. The GPS surveying with static survey method is performed to be compatible with thebenchmark system of the Royal Thai Survey Department (RTSD) based on the national coordinatingsystem. The generated coordinates are created by static survey using four dual-frequency GPSreceivers. The obtained raw data are processed by a specific software, SKI-PRO, yielding a set ofhigh accurate geographical and UTM coordinates referred to 3 referenced coordinate systems i.e.,WGS 84, Indian 1975 (the former designated parameters used by the RTSD), and Indian 1975 (thenew designated parameters used by the RTSD). The obtained coordinates have the average standarddeviations in all the eight benchmarks in the X, Y and Z axes of 0.545, 0.419 and 1.298 cm, respectively,which are corresponding to the high order of accuracy. The contributions from this project willprovide high accurate benchmarks and their base lines to improve any future triangulation surveyingand also to update any precise maps of both campuses and the surrounding areas.