Sunday, December 30, 2018

Planimeter

PLANIMETER:

planimeter, also known as a platometer, is a measuring instrument used to determine the area of an arbitrary two-dimensional shape.


  • It is a digital instrument which is used for measuring of small areas.
  • Method of uses has been shown below in the video. 



Market Value:

Approximately PKR 30000

PHOTO-THEODOLITE:

A photo-theodolite is a form of ground camera. It is a combination of camera and theodolite and is used for taking photographs and measuring the angles which the rival plane of collimation makes with the base line. Both the theodolite and camera rotate about a common vertical axis. This is used for terrestrial photogrammetry.


APPLICATION:

It is useful mapping construction, earthworks,plotting  tunnel profiles etc.


Market Value:

US $650 to 900 in PKR 90430.

ELECTRONIC THEODOLITE:

It is used to measure horizontal and vertical angles.

In modern electronic theodolite, the readout of horizontal and vertical circle is usually done with a rotary encoder. These produce signals indicating the altitude and azimuth of the telescope which fed to a microprocessor. CCD sensors have been added to the focal plane of the telescope allowing both auto-targeting and automated measurement of residual target offset. All this implemented in embedded software of processor.



Market Value:

Approximately US $700 to $ 900 in PKR 97387.



Auto Level


DEFINITION:

Auto level is a device used in survey to measure horizontal levels.



  •  Alidade is used for rough alignment.
  •  Eye piece is used for magnification and to read the staff reading.
  • Focusing screw is used to en-visible an object. 
  • Bubble tube for leveling of instrument. 


   MARKET VALUE
   
   Market value of auto level is  US $100-120 which is about 17000 PKR.

Theodolite

THEODOLITE:

A theodolite is versatile instrument basically designed to measure horizontal and vertical angles. It is also used to give horizontal and vertical distances using stadia hairs.


PARTS:
·        TELESCOPE has object piece at one end and eye piece at other end and its purpose to focus the object.  It rotates about horizontal axis in vertical plane. The graduations are up to an accuracy of 20’.
·        INDEX FRAME which is also called t-frame or vernier frame having two arms vertical and horizontal. It is used to lock the telescope at a desired level and its horizontal arm is used for taking measurements of vertical angles.
·        THE STANDARDS are also known as A-frame because of its shape. It supports telescope and allow it to rotate about vertical axis.
·        THE UPPER PLATE is also called vernier plate whose top surface gives support to telescope.
·        THE LOWER PLATE has a scale graduated from 0 to 360 that is why it is called scale plate. It can rotate by our willings.
·        THE LEVELLING HEAD contains two parallel triangular plates known as tribratch,the upper one is used to level the upper plate and telescope and lower one is attached to tripod stand.
·        THE SHIFTING HEAD also contains two parallel plates moving one over other with in small area, lies below the lower plate. It is used to center the whole instrument over the station.
·        PLATE LEVEL helps the telescope to settle in exact vertical position.



The purpose of telescope is to see the target.                                     

                          A small bubble is used for leveling of the instrument.         




Market Value: Price per piece of theodolite in US $ 600 to 700 in PKR 83475.