The check for traversing by deflection angle method in a closed traverse of n sides is

🧭 Understanding the Core Concept

In a closed traverse, the survey lines form a closed loop. There are several geometric checks to ensure the accuracy of the measured angles. When using the deflection angle method, the primary check is that the algebraic sum of all deflection angles must equal 360°.

A deflection angle is the angle between the extension of the previous line and the current line. Angles to the right (clockwise) are considered positive (+), and angles to the left (counter-clockwise) are considered negative (-).

📜 Properties of a Closed Traverse & Deflection Angle Check

For any closed traverse with 'n' sides, the following geometric properties hold true:

• Sum of Interior Angles = (2n - 4) × 90°
• Sum of Exterior Angles = (2n + 4) × 90°

Check for Deflection Angles:

The specific check when measuring deflection angles is as follows:

• The algebraic sum of all deflection angles should be 360°.
• This rule applies regardless of the number of sides (n) in the traverse. It confirms that the survey has returned to the starting point without angular error.