| Summary: | 碩士 === 國立宜蘭大學 === 土木工程學系碩士班 === 101 === When GPS static relative positioning is adopted to conduct measuring, usually reference stations are required to be setup at control points for conducting relative positioning, thus more measuring time, manpower and cost are required, while in recent years, domestic satellite base stations have been laid out in entire Taiwan, maybe those satellite base stations can be viewed as reference stations for relative positioning, thereby, the experiment conducts measuring with class 1, 2 satellite control points of Taipei and Yilan, and applies TWD97 and TWD97[2010] satellite base station data to conduct solving, so as to explore whether the results obtained through this approach could satisfy cadastral measuring standard requirements.
In the study, two approaches of VBS-RTK and static relative positioning are adopted to conduct measuring, for VBS-RTK, plane standard deviations in both areas are all within 2 cm, in Taipei area, the external accuracy can all reach requirement of maximum error within 6 cm of cadastral measuring implementation standards, but, in Yilan area, its average error needs to go through coordinate transformation to reach the standard value, but in singular data there is still parts exceeding 6 cm, so caring is needed in using.
When positioning data are solving with Yangming mountain base station TWD97 coordinates, as shown in the study, when base line distance is greater than 20 km, greater error will be occurred as commercial software is adopted for solving, if greater error point positions were excluded, the plane direction error of every point positions in Taipei area can be all within 6 cm, but in Yilan area, after coordinate transformation, there are still greater errors, after coordinate transformation, the error range are within 4.6 cm ~ 57.4 cm.
To conduct solving with data of satellite base station adjacent to each point position, owing to TWD97[2010] satellite base station data are used for solving, the data are closer to results from TWD97[2010], however, if comparing to TWD97 is attempted then coordinate transformation is required, after coordinate transformation, in Taipei area, the plane direction errors can all be controlled within 6 cm, while in Yilan area, owing to inconsistency in errors the transformation efficacy is not obvious, where the error range after correction are between 6.5 cm ~ 20.2 cm. As the study results shown, in Taipei area, where error variation range are not great in the area, relative positioning can be conducted by downloading satellite base station, but in eastern area and area of greater plate movement, such approach is relatively not appropriate to be adopted for conducting measuring.
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