🧠Classification of Surveying Based on Instruments Used
Surveys are often classified based on the instruments used for measurement. Here's a breakdown of major types:1. Chain Survey
The simplest form of survey using only chains or tapes for measuring distances.- Used for small areas with clear ground.
- No angle measurements are taken.
- Highly suitable for plain terrain.
2. Compass Survey
This survey uses a compass to measure horizontal angles and a chain for distances.- Suitable for large areas with undulating ground.
- Quick but affected by magnetic interference.
- Less accurate than theodolite survey.
3. Levelling
This method determines the elevation of points using a level instrument.- Used for road and canal projects.
- Helps in creating contour maps.
- Only vertical measurements are taken.
4. Plane Table Survey
Here, observations and plotting are done simultaneously in the field using a plane table.- Ideal for small-scale surveys.
- Provides real-time mapping.
- Not suitable in rainy or windy conditions.
5. Theodolite Survey
Uses a theodolite to measure both horizontal and vertical angles.- Highly accurate and versatile.
- Used in triangulation and traversing.
- Essential for large engineering projects.
6. Tacheometric Survey
A rapid survey method using a tacheometer to measure distance and elevation.- Ideal for rough terrain.
- No need for chaining across steep slopes.
- Used in hydrographic and topographic work.
7. Photogrammetric Survey
Involves taking photographs from aircraft and using them to create maps.- Used for topographic surveys over large areas.
- Very useful in remote and inaccessible regions.
- Requires special instruments and training.
8. EDM Survey
Electronic Distance Measurement uses instruments like total stations to calculate distances.- Highly accurate and fast.
- Used in modern surveying and GIS mapping.
- Based on trilateration.
Conclusion: Knowing which instruments to use is crucial for selecting the best surveying method — from simple chains to high-tech EDM tools, each has a unique role in measurement and mapping.
