What is stadia tacheometry?
Tacheometry is a branch of angular surveying in which the horizontal and vertical distances are obtained by optical means as opposed to the ordinary process of chain and tape. This is done with the help of two special type of instruments- transit theodolite and stadia rod.
What is the purpose of tacheometry?
The primary objective of this tacheometric surveying is to prepare contoured maps or plans requiring both the horizontal as well as vertical control. On surveys of higher accuracy, it provides a check on distances measured with the tape.
What do you mean by tacheometry give principles of tacheometry?
Principle of Tacheometric Surveying The principle of tacheometric surveying is based on the property of an isosceles triangle. It means that; the ratio of the distance of the base from the apex and the length of the base is always constant.
What is tacheometry method?
Tacheometry (/ˌtækiˈɒmɪtri/; from Greek for “quick measure”) is a system of rapid surveying, by which the horizontal and vertical positions of points on the earth’s surface relative to one another are determined without using a chain or tape, or a separate levelling instrument.
What is the difference between stadia and tangential method of tacheometry?
In stadia system a telescope is fitted with stadia hair in movable hair method. In tangential system a telescope is not fitted with stadia diaphragm. Two vane or targets are fixed at a known distance apart a normally 3m. Two target are fixed distance apart is probably 3m to 4m.
What is stadia interval factor?
Stadia interval factor is the ratio of the focal distance to the distance between the stadia hairs, which for a particular instrument is a constant as long as conditions remain unchanged.
What are the advantages and disadvantages of tacheometry?
Advantages of Tacheometric Surveying
- Speed of surveying is very high.
- Accuracy of surveying is quite satisfactory in normal conditions and even superior in difficult terrain.
- Cost of surveying is less.
- Not tedious as chain, tapes, ranging rods, etc, are avoided.
- The method is more advantageous in the following works:
What is Tacheometry what is its principle explain with neat diagram?
INSTRUMENTS USED: An ordinary transit theodolite fitted with a stadia diaphragm is generally used for tacheometric survey. Principle of tacheometry: The principle of tacheometer is based on property of isosceles triangles, where the ratio of distance of the base from apex and length of the base is always constant.
What are essential requirements of Tacheometry?
Essential requirements of tacheometer:
- Firstly a tacheometer is usually a transit theodolite having a stadia diaphragm.
- Lastly the telescope of tacheometer may be.
Which method of tacheometry is most common in use?
stadia Method Fixed stadia method
In stadia Method Fixed stadia method is commonly used.
What is stadia constant?
The stadia marks are set a specific length apart. This length is chosen so that there is a fixed, integer ratio between the difference of the rod readings and the distance from the telescope to the rod. This ratio is known as the stadia constant or stadia interval factor.