Survey 3


Traverse is one of the most important task for skilled surveying engineer. It is used to find out coordinates of new control points (or stations). Once control points are established, they can serve either as a part of a network of control points or a base control points for a given construction project.

Since unclosed traverses can not be checked for an error, usually closed traverses are preferred. Closing the loop can be done eg. by overlapping starting and ending point or by targeting the traverse against some of the current control points.

For purpose of our survey: close the traverse into the starting point.

Types of traverse: open and closed traverse
Map of Area around Zaman. Note that triangulation or trilateration can not be employed due to the obstacles (buildings)

The equipment

We will work with total station + its target (prism). To achieve a high degree of accuracy more reading of one value needs to be made: to cancel some instrument systematic errors, make readings with telescope sight forward. Once reading of backsight and foresight is finished, rotate the telescope around its trunnion axis to make other reading: from foresight to backsight. Record all readings. Make a check for a blunder in the field.

Trunnion axis of the telescope. To achieve a high degree of accuracy, make a reading with the telescope both forward and then rotated.

Important notes

The procedure

The task is to find out coordinates of the stations. For traverse, we need to measure all distances and all angles, then the data reduction can be made.

Data reduction

We are not fixed by any current control points. Thus, assume that coordinates of A = [0 N, 0 E] and azimuth AB is 115°. Use transit rule to evaluate the traverse.

Evaluate and discuss the accuracy of the measurement.

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