Surveying

  Errors in linear Managements(Chain survey) A.   On the basis of source of error:   Instrumental error  Personal error  natural error 1.  Instrumental error:  Error which occurs due to faulty adjustment or imperfection of the instrument with which the measurement is being taken is known as instrumental error. It can be eliminated or minimized by adopting suitable procedures and by applying proper correction and adjustment.     For Eg.  :   If the tape used in measurement of distance is actually 30.10 m long where as nominal length is 30 m, the error occurs because of the imperfect tape called instrumental error.   2.  Personal error:  The personal error occurs due to human limitation , fault such as sense of sight and touch.the errors occurs for want of perfection of human sight while taking observation or for want of perfection of touch while manipulating the instrument. For Eg.  :  A distance of 1.444 m may be estimated as 1.445 m  or 1.443 m. 3.  Natural error:  The error which ari

  Total station Total station is a combination of theodolite, level, EDM, microprocessor with a specific memory. Total station integrates the functions of a theodolite for measuring angles, an EDM for measuring distances, digital data & data recorder. From this instrument distance, angle, height difference, co-ordinate, area, bearing, perimeter etc. can be easily measured. Its accuracy was in part per million (ppm). It can measured slope distance directly. Topcon, sokia, pentex, Nicon, Leica, Stonex, etc. are the model of total station. Features and Uses of Total station: Total Solution for surveying work   Most accurate of user friendly   Gives position of point (X, Y, Z) W.R.T. known point   EDM was fitted inside Telescope   on board memory to store data  Digital display   Compatibility with computers can be used for carry layout Functions of Total station: 1. It simultaneously measures angle of distance  & record  2.  Correcting the measured distance with.     prism constant

 INDIRECT DISTANCE MEASUREMENT We discussed on the topic of direct distance measuring instrument on another post . on this we will discuss on the topic of Indirect distance measuring instrument. The method of direct distance measurement is unsuitable in difficult terrain and sometimes Impossible when obstructions occurs. on that condition Indirect Method comes in use.

 DISTANCE MEASURING INSTRUMENT To know about the distance measuring instrument first off all we have to know about distance. What is distance? It is length between any two specific point which you want to measure or we fixed on ground. and the instrument which used to measure the length are the distance measuring instruments.   Distance can be measured directly and indirectly with the help of instruments.  On the basics of direct method and indirect method instruments are categorized into two parts, i.e.    A.  Direct Distance measuring instruments B.  Indirect Distance measuring instruments Direct Distance measuring instruments: Direct distance measuring instruments are those types of instrument which used to give the distance / length between any two point at the time of measurement on the field directly without any mathematically calculation or without help of any other instruments. Direct distance measuring instruments are : 1. Chain 2. Tape Chain: It is direct distance measuring i