Application of Least Squares Estimation Techniques in 2D Conformal Coordinates Transformation from Local to National

Abstract

A two-dimensional conformal coordinate transformation is a similarity transformation which is also known as the four parameter transformation since it maintains scale relationships between the two coordinates system. This transformation type uses a mathematical model that establish a geometrical relationship between coordinates of points in different reference frames. It gained wider acceptance because of its capability to retain the shape of an area represented. This paper utilizes three control points; PT02, PT03 and PT04 to compute the transformation parameters and later all validated the derived coordinates of point PT04 known in the local system to national system using manual computation check. The second approach was to derive the transformation parameters using four control points. The result obtained was validated and found to agree with the derived national coordinates system for point PT07. Subsequently, all other points within the areas covered in the scope of work were transformed by writing script and running it in MATLAB software environment. The total area covered was 457.457hectares.

Geodetic control extension at erosion prone areas using integrated CORS-GNSS in Benin City, Edo State Nigeria

“…In the same manner, the standard deviation in height of (3.5 mm) was recorded at stations AGGS_01 and AGGS_02, the minimum accuracy was (2.8 mm) at QSS01. The horizontal coordinates are more accurate in all cases compare to the vertical coordinates for the stations, the accuracy obtained is in consistence with (Ehigiator et al, 2017a: Fotiou et al, 2006: Botsyo et al, 2020. Table 3, contains the adjusted points in the target system.…”