A Comparative Study Between Three Different Adjustment Techniques as Applied to Part of the Old Sudanese Triangulation Networks

Abstract

Triangulation in survey is the process of determining the control points by measuring angles and distances. The adjustment process of triangulating a network can be carried out by many methods, one of these methods is variation of coordinates using distance, angle and azimuth observation equation. The objective of this study was to use the variation of coordinates method by distance observation equation only. The network has been adjusted was a part of an old triangulation in Sudan, three techniques of adjustment were implemented, the first technique is using plane distance without weights, and in the second one is using weights on plane distance and in the last technique some of the distances were too long. Therefore, the curvature correction was added to the distance and a new adjustment was performed. The results emphasized that the technique of adding curvature gives better adjusted values. Nonetheless, the three techniques gave more or less same values, but the difference from the original coordinates were tremendously large. This shows that the new technique is likely to approximate the true value of the coordinates.