trigonometric leveling
The effect of atmospheric refraction error on observed value is a very thorny problem in EDM trigonometric leveling.
Applying the measuring principle of the trigonometric leveling with total station into the construction of urban pipeline engineering can replace the traditional geometric leveling method.
Considering the collimation error and atmospheric vertical refraction error are larger at daytime, a method of night trigonometric leveling is proposed and the height measurement accuracy is analyzed.
Elevation difference by trigonometric leveling shall be corrected by spherical aberration.
The traditional methods are geometrical leveling and trigonometric leveling. They have different advantage and disadvantage.