1. What is Deflection Angle in Surveying?

Deflection angle is the angle between the prolongation of the preceding line and the following line in a traverse. It is commonly used in route surveys and traverse computations to determine the direction change at each station.

2. How Does the Calculator Work?

The calculator uses the deflection angle formula:

Where:

• \( \text{Interior Angle} \) — The internal angle measured at the station between two consecutive traverse legs
• \( 180° \) — The straight angle used as reference

Explanation: The deflection angle represents how much the survey line deviates from the straight line continuation of the previous line.

3. Importance of Deflection Angle Calculation

Details: Accurate deflection angle calculation is crucial for traverse computations, route alignment design, and ensuring proper closure of survey networks. It helps in determining the direction of each traverse leg and calculating coordinates.

4. Using the Calculator

Tips: Enter the interior angle measured at the station in degrees. The value must be between 0° and 180°. The calculator will compute the corresponding deflection angle.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between deflection angle and interior angle?
A: Interior angle is the angle inside a closed traverse, while deflection angle is the angle between the prolongation of the previous line and the current line, used in open traverses.

Q2: Can deflection angles be positive or negative?
A: Yes, deflection angles can be positive (right deflection) or negative (left deflection) depending on the direction of the turn from the prolongation of the previous line.

Q3: What is the typical range for deflection angles?
A: Deflection angles typically range from -180° to +180°, with positive values indicating right turns and negative values indicating left turns.

Q4: How are deflection angles used in traverse computations?
A: Deflection angles are used to calculate bearings or azimuths of traverse legs, which are then used for coordinate calculations and traverse adjustment.

Q5: What precautions should be taken when measuring interior angles?
A: Ensure the instrument is properly leveled, use appropriate observation techniques (direct and reverse), and take multiple measurements to minimize errors.